Wi-Fi g Let8217s cercare di ricapitolare tutta la suggestione dal giorno 2 della LAN Pro Conferenza wireless. Tanti grandi presentazioni, da molti presentatori di talento, che coprono alcune molto rilevanti contenuti Wi-Fi. Poi il giorno finito forte con un'altra sessione produttore impressionante Alcuni punti salienti del Day 2: raccogliere i requisiti prima di progettare Lee Badman (wirednot) ha fatto un impressionante consegnare un messaggio altrettanto divertente e importante sull'importanza della raccolta dei requisiti prima di progettare. Esempio: Requisito 1 8211 Il sistema can8217t succhiare Leggi tutto rsaquo Hi, It8217s stato un grande primo giorno qui al tutto esaurito senza fili Conferenza Pro (WLPC) 2017 a Phoenix, con tonnellate di grandi oratori, e carichi di conoscenze Wi-Fi condivisione. Un paio di punti salienti della prima giornata di seguito. Cercheremo anche di follow-up con riassunti di giorni 2 AMP 3 quindi rimanete sintonizzati. Per saperne di più visita rsaquo Aruba Atmosphere a Nashville il 26 febbraio 8211 3 marzo venite a dare un abbraccio, siamo allo stand 5. Jussi sta dando una presentazione alla conferenza pure. Don8217t perdere Topic: 822010 Essentials Ogni tecnico deve Know8221 tempo Data AMP: Mercoledì 1 marzo, 01:45 8211 15:00 Luogo: Gaylord Opryland Resort. Leggi tutto rsaquo AP Nome trasmissione è una funzione opzionale implementato da alcuni dei fornitori Wi-Fi che consentono ad un punto di accesso per pubblicizzare il nome host unità, in genere entro le strutture del falò. Se attivata, questa funzione consente Ekahau Site Survey per identificare i Nomi punti di accesso durante un rilevamento Questa capacità di identificare e popolare il nome AP. Per saperne di più rsaquo D: Tu sei un consulente WLAN con il compito di progettare una rete WLAN con planimetrie CAD. Dopo aver importato il file. dwg e assegnare i tipi di parete utilizzando la delineando guidata muro, si prepara per aggiungere punti di accesso simulati al progetto. Si scopre che la combinazione di AP, Antenna o AP-antenna che si desidera progettare con non lo è. Leggi tutto rsaquo Andando a BICSI conferenza Winter in Tampa questo mese Incontra allo stand 509 per dire ciao e vedere una demo Oh, e abbiamo qualche piano espositivo passa per voi, in modo da entrare in contatto, se si vuole ottenere uno. ) Inoltre, presentazione don8217t perdere Jussi8217s alla conferenza. Topic: 8220Walking è buona. Leggi tutto rsaquo Il nostro programma webinar per il 2017 si sta riempiendo bene e abbiamo una grande line-up di ospiti presentatori per quest'anno controlla la lista qui sotto ed essere sicuri di iscriversi per le notifiche blog e-mail per ricevere i promemoria per i prossimi webinar. 7 modi per fallire come un esperto senza fili con Steven Heinsius di Cisco. Leggi tutto rsaquo 2016 è stato un grande anno per noi di Ekahau. Un sacco di cose nuove, un sacco di cambiamenti. Ecco solo alcune: 1) Prodotto: Rilasciato versioni 8,5 e 8,6 con l'integrazione analizzatore di spettro, tutto-nuova funzionalità Real-Time Frequency Monitor, e un paio di centinaia di altre cose. La versione per Mac è stata pubblicata come versione beta. 2) Marketing: Abbiamo fatto un sacco di spettacoli: Cisco Live. Per saperne di più rsaquo L'ospite del nostro prossimo webinar è Steven Heinsius di Cisco se stesso. Steven è uno dei Cisco8217s altoparlanti più votati. Quando Steven parla, la sala conferenze, indipendentemente dalle dimensioni, si riempie 8211 e menti vengono soffiati a destra ea sinistra. Il webinar è dedicata alle migliori pratiche a condurre una installazione di rete wireless. Don8217t. Leggi tutto rsaquo Un grande grazie a tutti i nostri 2016 presentatori ospiti webinar Nel caso in cui vi siete persi uno qualsiasi dei nostri webinar passati, controllare le registrazioni qui sotto o vedere la lista completa delle registrazioni di webinar sul nostro canale YouTube Slideshare utilizza i cookie per migliorare la funzionalità e le prestazioni , e per fornire voi con la pubblicità in questione. Se si continua la navigazione nel sito, l'utente accetta l'utilizzo dei cookie su questo sito. Vedi le Condizioni d'uso e sulla privacy. Slideshare utilizza i cookie per migliorare la funzionalità e le prestazioni, e per fornire voi con la pubblicità in questione. Se si continua la navigazione nel sito, l'utente accetta l'utilizzo dei cookie su questo sito. Vedi le Condizioni d'uso per i dettagli sulla privacy e. Vedi tuoi argomenti preferiti in app SlideShare Scarica l'applicazione SlideShare di Offerta ricordare anche offline Continuare a sito mobile Carica Accesso Registrazione Doppio tap per diminuire Condividi questo SlideShare LinkedIn Corporation copia 2017Cisco CleanAir - Cisco Unified intelligenza Wireless Network Design Guide Spectrum ( sI) è una tecnologia di base progettato per gestire in modo proattivo le sfide di uno spettro wireless condivisa. Essenzialmente, SI porta algoritmi di identificazione interferenze avanzati simili a quelli utilizzati in campo militare al mondo rete wireless commerciale. SI fornisce visibilità a tutti gli utenti dello spettro condiviso, sia Wi-Fi dispositivi e interferenti estere. Per ogni dispositivo che opera nella banda senza licenza, SI ti dice: Che cosa è Dove si trova Come influisce la rete Wi-Fi Cisco ha compiuto il passo audace di integrare SI direttamente nella soluzione di silicio e l'infrastruttura Wi-Fi. La soluzione integrata, denominata Cisco CleanAir, significa che per la prima volta direttore WLAN IT è in grado di identificare e localizzare le fonti di interferenza non-802.11, che alza la barra sulla facilità di gestione e la sicurezza delle reti wireless. Ancora più importante, un SI integrato pone le basi per una nuova generazione di Radio Resource Management (RRM). A differenza delle soluzioni RRM precedenti, che non poteva che comprendere e adattarsi ad altri dispositivi Wi-Fi, SI apre la strada per una soluzione RRM di seconda generazione che è pienamente consapevole di tutti gli utenti dello spettro radio, ed è in grado di ottimizzare le prestazioni in faccia di questi dispositivi vari. Il primo punto importante che deve essere fatto è che da un punto di vista progettuale. CleanAir abilitato punti di accesso (AP) sono solo che i punti di accesso e le prestazioni sono praticamente identici ai 1140 punti di accesso. Progettare per la copertura Wi-Fi è lo stesso con entrambi. CleanAir o processi di identificazione di interferenza sono un processo passivo. CleanAir si basa sul ricevitore, e per la classificazione di funzionare, la sorgente deve essere abbastanza forte da essere ricevuto a 10 dB sopra il rumore di fondo. Se la rete è distribuito in modo tale che i vostri clienti e punti di accesso possono sentire l'un l'altro, poi CleanAir può sentire abbastanza bene per avvisare l'utente di interferenze preoccupante all'interno della rete. I requisiti di copertura per CleanAir sono descritti in questo documento. Ci sono alcuni casi particolari a seconda del percorso di attuazione CleanAir è in ultima analisi scegliere. La tecnologia è stata progettata per complimentarmi con le migliori pratiche correnti in distribuzione Wi-Fi. Questo include i modelli di implementazione di altre tecnologie ampiamente utilizzati come Adaptive WIPS, voce e implementazioni posizione. Cisco consiglia di avere la conoscenza di CAPWAP e Cisco Unified Wireless Network (CUWN). Le informazioni contenute in questo documento si basa su queste versioni software e hardware: AP capaci CleanAir sono Aironet 3502e, 3501e, 3502i e 3501i Cisco WLAN Controller (WLC) in esecuzione la versione 7.0.98.0 di Cisco Wireless Control System (WCS) versione in esecuzione 7.0.164.0 Cisco Mobility Services Engine versione (MSE) in esecuzione 7.0 Fare riferimento a convenzioni Cisco suggerimenti tecnici per ulteriori informazioni sulle convenzioni di documenti. CleanAir è un sistema, non è una caratteristica. software CleanAir componenti hardware e offrono la possibilità di misurare con precisione la qualità-Wi Fi Channel e di identificare le fonti di interferenza canale non-Wi-Fi. Questo non può essere fatto con un chipset Wi-Fi standard. Al fine di comprendere gli obiettivi e requisiti per un'implementazione di successo di progettazione, è necessario capire come funziona CleanAir a un livello elevato. Per chi ha già familiarità con la tecnologia Ciscos Spectrum Expert, CleanAir è un passo evolutivo naturale. Ma, è una nuova tecnologia che si tratta di una tecnologia di analisi dello spettro distribuito basato enterprise. Come tale, è simile a Cisco Spectrum Expert in alcuni aspetti, ma molto diversa in altri. I componenti, le funzioni e le caratteristiche sono discussi in questo documento. I punti di accesso capaci nuovo CleanAir sono Aironet 3502e, 3501e, 3502i e 3501i. L'e designa antenna esterna, il che indica antenna interna. Entrambi sono pienamente funzionali AP 802.11n di prossima generazione ed eseguire sul potere 802.3af standard. Figura 1: C3502E e C3502I CleanAir AP Capace L'hardware di analisi dello spettro è direttamente integrato nel chipset della radio. Questa aggiunta ha aggiunto più di 500 K porte logiche alla Silicon Radio, e ha fornito eccezionalmente stretto accoppiamento delle caratteristiche. Ci sono molte altre caratteristiche tradizionali, che sono stati aggiunti o migliorati con queste radio. Ma, è oltre la portata di questo documento e questi non sono coperti qui. Basti per dire, che da solo senza CleanAir i punti di accesso della serie 3500 in valigia un sacco di funzionalità e prestazioni in un attraente e robusta impresa AP. L'architettura di base Cisco CleanAir è costituito da Cisco CleanAir ha permesso AP e un controller Cisco WLAN (WLC). Cisco Wireless System Control (WCS) e Mobility Services Engine (MSE) sono i componenti del sistema opzionali. Al fine di ottenere il pieno valore dalle informazioni che le forniture di sistema CleanAir, il WCS e MSE insieme sono fondamentali per sfruttare una più ampia efficacia di CleanAir. Questo fornisce interfacce utente per le funzionalità di spettro avanzate come i grafici storici, il monitoraggio dei dispositivi di interferenza, servizi di localizzazione e analisi di impatto. Un AP dotato di tecnologia Cisco CleanAir raccoglie informazioni su fonti di disturbo non Wi-Fi, elaborarli e trasmettere al WLC. Il WLC è parte integrante del nucleo del sistema CleanAir. I controlli WLC e configura CleanAir AP capaci, raccoglie ed elabora i dati dello spettro e le fornisce al WCS Andor MSE. Il WLC fornisce interfacce utente locali (GUI e CLI) per configurare le funzioni e servizi CleanAir di base e visualizzare le informazioni spettro corrente. Il Cisco WCS fornisce interfacce utente avanzate per CleanAir che includono funzionalità di abilitazione e di configurazione, visualizzazione delle informazioni consolidate, record storici Qualità dell'aria e motori di reporting. Figura 2: Logical System flusso Cisco MSE è richiesto per la localizzazione e il tracciamento storico di dispositivi di interferenza, e fornisce il coordinamento e il consolidamento di rapporti di interferenza tra più WLCs. Nota: Un singolo WLC può consolidare solo avvisi di interferenza per i punti di accesso direttamente ad esso collegati. Coordinamento delle segnalazioni che provengono da punti di accesso collegati a diversi controllori richiede l'MSE che ha una visione ampia del sistema di tutti CleanAir AP e WLCs. Il cuore del sistema CleanAir è l'ASIC Spectrum Analysis Engine (SAGE), l'analizzatore di spettro su un chip. Tuttavia, è molto più di un analizzatore di spettro. Al centro è un potente motore di FFT 256 punti che fornisce una sorprendente 78 KHz RBW (Larghezza di banda Risoluzione, la risoluzione minima che può essere visualizzato) motori appositamente costruito polso e la raccolta di statistiche così come il DSP accelerata Vector Engine (Dave). L'hardware di salvia corre in parallelo con il chipset Wi-Fi e processi nei pressi informazioni velocità di linea. Tutto ciò consente estrema precisione e bilance industriali per un gran numero di fonti di interferenza come, senza alcuna penalità in un throughput di traffico degli utenti. Il chipset Wi-Fi è sempre on line. scansioni salvia vengono effettuati una volta al secondo. Se viene rilevato un preambolo Wi-Fi, viene passato attraverso il chipset direttamente e non è influenzata dall'hardware SAGE parallelo. Non pacchetti vengono persi durante la scansione Sage, Sage è disabilitata mentre un pacchetto di connessione Wi-Fi viene elaborato attraverso il ricevitore. Sage è molto veloce e preciso. Anche in un ambiente occupato, vi è più di tempo di scansione sufficiente per valutare con precisione l'ambiente. Perché RBW importa se avete bisogno di contare e misurare la differenza tra diverse radio Bluetooth saltellando con segnali stretti a 1600 salti al secondo, è necessario separare diversi trasmettitori luppolo nel campione se volete sapere quanti ce ne sono. Questo richiede risoluzione. In caso contrario, sarebbe tutto simile a un impulso. Sage fa questo, e lo fa bene. A causa della Dave e di essere associati memoria a bordo, la capacità di elaborare più samplesinterferers in parallelo c'è. Questo aumenta la velocità, che consente di elaborare il flusso di dati in tempo quasi reale. Vicino tempo reale significa che c'è un certo ritardo, ma è talmente minima che serve un computer per misurarla. Cisco CleanAir AP producono due tipi fondamentali di informazioni per il sistema CleanAir. Un IDR (Interference dispositivo Report) viene generato per ogni fonte di interferenza classificato. AQIS (Air Quality Index) i report vengono generati ogni 15 secondi e passati al Cisco IOS reg per la media e la trasmissione finale al controllore in base all'intervallo configurato. messaggistica CleanAir è tutto gestito sul piano di controllo in due nuovi tipi di messaggi CAPWAP: Spettro di configurazione e Spectrum dati. I formati di questi messaggi sono elencate qui: i dati di spettro AP WLC Il Rapporto Anomalia (IDR) è un rapporto dettagliato che contiene informazioni su un dispositivo di interferenza classificato. Questo rapporto è molto simile alle informazioni che si vede in Cisco Spectrum Expert periferiche attive, o dispositivi View. IDR attivi possono essere visualizzati sul WLC GUIand CLI per tutte le radio CleanAir su quel WLC. IDR vengono inoltrati solo al MSE. Questo è il formato per un rapporto IDR: Tabella 1 - Interferenza dispositivo Rapporto Nota: le fonti di interferenza contrassegnati come Security interferenti sono designati utente e può essere configurato tramite Wireless GT 802.11abgn gt CleanAir GT consentire interferenze per l'allarme di sicurezza. Qualsiasi fonte di interferenza che viene classificato può essere scelto per un allarme di sicurezza trappola. Questo invia una trappola di sicurezza al WCS o altro ricevitore trap configurato in base al tipo di interferente selezionato. Questa trappola non contiene le stesse informazioni di un IDR. È semplicemente un modo per attivare un allarme sulla presenza del interferente. Quando un interferente è designato come un problema di sicurezza, è contrassegnato come tali al AP ed è sempre incluso nei dieci dispositivi che vengono segnalati dal AP indipendentemente dalla gravità. messaggi IDR vengono inviati in tempo reale. Al rilevamento del IDR è contrassegnato come dispositivo su. Se si ferma un dispositivo verso il basso viene inviato il messaggio. Un messaggio di aggiornamento viene inviato ogni 90 secondi dalla AP per tutti i dispositivi correntemente inseguiti. Questo permette di aggiornamenti di stato di fonti di disturbo cingolati e una pista di controllo nel caso in cui un messaggio su o in giù è stato perso in transito. Qualità dell'aria (AQ) segnalazione è disponibile da qualsiasi spettro capace AP. La qualità dell'aria è un nuovo concetto con CleanAir e rappresenta una metrica bontà dello spettro disponibile e indica la qualità della larghezza di banda disponibile per il canale Wi-Fi. La qualità dell'aria è una media mobile che valuta l'impatto di tutti i dispositivi di interferenza classificati contro uno spettro perfetto teorica. La scala è 0-100 100 rappresenta Good. rapporti AQ vengono inviati in modo indipendente per ogni radio. L'ultimo rapporto AQ è visualizzabile sulla GUI WLC e CLI. rapporti AQ vengono memorizzati sul WLC e interpellati da WCS intervalli regolari. Il valore predefinito è 15 minuti (minimo) e può essere esteso a 60 minuti sul WCS. Attualmente, i chip Wi-Fi più standard valutano spettro tracciando tutte le packetsenergy che può essere demodulato in ricezione, e tutto il packetsenergy che sta trasmettendo. Ogni energia che rimane nello spettro che non può essere demodulato o rappresentato dall'attività RXTX è aggregate in una categoria chiamata rumore. In realtà, un sacco di rumore è in realtà resti di collisioni, o pacchetti Wi-Fi che non superano la soglia di ricezione per la demodulazione affidabile. Con CleanAir, viene adottato un approccio diverso. Tutta l'energia all'interno dello spettro che è sicuramente non Wi-Fi è classificato e contabilizzato. Possiamo anche vedere e capire l'energia che viene modulato 802.11 e classificare l'energia che arriva dal Co-canali e fonti canale adiacente. Per ogni dispositivo classificato un indice di gravità è calcolato (vedere la sezione gravità), un numero intero positivo compreso tra 0 e 100, con 100 è il più grave. gravità interferenza è quindi sottratto dalla scala AQ (a partire da 100 buono) per generare l'attuale AQ per un channelradio, AP, Pavimento, o campus. AQ allora è una misura dell'impatto di tutti i dispositivi classificati sull'ambiente. Ci sono due modi di AQ segnalazione definiti: aggiornamento normale e rapida. Modalità Normale è la modalità di segnalazione di default AQ. O il WCS o il WLC recupera relazioni a normale velocità di aggiornamento (di default è di 15 minuti). Il WCS informa il controller sul periodo di polling predefinito, ed il WLC istruisce l'AP di cambiare AQ media e il periodo di riferimento di conseguenza. Quando le esercitazioni utente verso il basso per monitorare i punti di accesso gt gt e sceglie una interfaccia radio dal WCS o il WLC, la radio selezionato viene posizionato in modalità di segnalazione di aggiornamento rapido. Quando si riceve una richiesta, il Controllore indica al AP per modificare il periodo di riferimento di default AQ temporaneamente ad un tasso fisso veloce aggiornamento (30 sec), che consente pressi visibilità in tempo reale in AQ cambia a livello di radio. paese di registrazione di default è ON. Tabella 3: Air Quality Report Nota: Nel contesto della segnalazione spettro, Qualità dell'aria rappresenta interferenze da fonti non-Wi-Fi e fonti Wi-Fi non rilevabili da un AP Wi-Fi durante il normale funzionamento (ad esempio, vecchio tramoggia 802.11 frequenza dispositivi, alterati periferiche 802.11, adiacente sovrapposizione interferenze dei canali, ecc). Informazioni su interferenza base Wi-Fi viene raccolto e riportato da AP utilizzando il chip Wi-Fi. Una modalità locale AP raccoglie informazioni AQ per il canale porzione corrente (s). Una modalità monitor AP raccoglie le informazioni per tutti i canali configurati sotto opzioni di scansione. Le impostazioni standard di CUWN Paese, DCA, e Tutti i canali sono supportati. Quando si riceve un rapporto di AQ, il controllore esegue richiesto l'elaborazione e la memorizzazione nel database AQ. Come accennato in precedenza, CleanAir è l'integrazione della tecnologia Cisco Spectrum Expert all'interno di una Cisco AP. Mentre possano esistere somiglianze, questo è un uso fresca della tecnologia e molti nuovi concetti sono rappresentati in questa sezione. Cisco Spectrum Expert introdotto la tecnologia che è in grado di identificare positivamente le fonti di energia radio non Wi-Fi. Ciò ha permesso all'operatore di concentrarsi su informazioni quali canali del ciclo di dovere e di funzionamento, e prendere una decisione informata circa il dispositivo e il suo impatto sulla loro rete Wi-Fi. Spectrum Expert ha permesso all'operatore di quindi bloccare il segnale prescelto nell'applicazione dispositivo Finder e localizzare fisicamente il dispositivo in giro con lo strumento. L'obiettivo di progettazione di CleanAir è quello di fare qualche passo ulteriore, eliminando sostanzialmente l'operatore più lontano dalla equazione e automatizzare molti dei compiti all'interno del sistema di gestione. Poiché è possibile conoscere ciò che il dispositivo è e ciò che sta interessando, decisioni migliori possono essere fatte a livello di sistema su cosa fare con le informazioni. Diversi nuovi algoritmi sono stati sviluppati per aggiungere intelligenza al lavoro che è stato avviato con Cisco Spectrum Expert. Ci sono sempre casi che richiedono fisicamente invalidanti un dispositivo di interferenza, o prendere una decisione su un dispositivo e l'impatto che coinvolge gli esseri umani. Il sistema nel suo complesso dovrebbe guarire ciò che può essere guarita ed evitare ciò che può essere evitato in modo che lo sforzo di recuperare spettro interessata può essere un esercizio attivo invece di un reattivo. Modalità locale AP (consigliato) (LMAP) A Cisco CleanAir AP opera in modalità LMAP sta servendo i clienti sul suo canale assegnato. Essa sorveglia inoltre Spectrum su quel canale e che solo canale. l'integrazione di silicio stretto con la radio Wi-Fi consente l'hardware CleanAir per ascoltare tra il traffico sul canale che è attualmente servito con assolutamente nessuna penalità per il throughput di client collegati. Questo è il rilevamento di velocità di linea senza interrompere il traffico client. Non ci sono CleanAir abita elaborato durante le normali scansioni canale off. Nel funzionamento normale, una modalità CUWN locale AP esegue un off canale scansioni passivi degli alternativi canali disponibili a 2,4 GHz e 5 GHz. Off Canale scansioni vengono utilizzati per la manutenzione del sistema, come metriche RRM e rilevamento rogue. La frequenza di queste scansioni non è sufficiente a raccogliere ritorna indietro abita richiesto per la classificazione dispositivo positiva, quindi le informazioni raccolte durante questa scansione è soppressa dal sistema. Aumentare la frequenza delle scansioni canale off è, inoltre, non auspicabile, in quanto toglie dal momento che il traffico servizi radio. Che cosa significa tutto questo Un CleanAir AP in modalità LMAP esegue la scansione solo un canale di ciascuna banda in continuo. In normali densità enterprise ci dovrebbero essere molti AP sullo stesso canale, e almeno uno su ogni canale assumendo RRM sta gestendo canali. Una fonte di interferenza che utilizza la modulazione a banda stretta (opera su o intorno a una singola frequenza) viene rilevato solo da punti di accesso che condividono lo spazio di frequenza. Se l'interferenza è un tipo di salti di frequenza (utilizza frequenze multiple in generale che copre tutta la band) viene rilevato da tutti gli AP in grado di sentire che operano nella banda. Figura 4: LMAP AP esempio il rilevamento 2.4 GHz, LMAPs hanno densità sufficiente a garantire in generale almeno tre punti di classificazione. è richiesto un minimo di tre punti di rilevamento per la risoluzione posizione. In 5 GHz, ci sono 22 canali operanti negli Stati Uniti, in tal modo la densità di rilevamento e sufficiente densità posizione è meno probabile. Tuttavia, se l'interferenza sta operando su un canale occupato da un CleanAir AP, lo rileva e di allarme o di adottare misure per mitigare se queste funzioni sono attivate. Più interferenza visto è limitata alla porzione 5,8 GHz della banda. Questo è dove i dispositivi consumer vivono e quindi dove è più probabile essere incontrato. È possibile limitare il vostro piano di canale per forza più punti di accesso a questo spazio se volete. Tuttavia, non è davvero giustificata. Ricordate, l'interferenza è un problema solo se si sta usando lo spettro è necessario. Se il vostro AP non è su quel canale, è probabile che si ha ancora un sacco di spettro a sinistra per muoversi in. Che cosa succede se la necessità di monitorare tutti di 5 GHz è guidato dalla sicurezza politiche Vedere la definizione Monitor modalità AP sotto. Monitor modalità AP (opzionale) Modalità (MMAP) A CleanAir Monitor AP è dedicato e non serve il traffico client. Esso fornisce una scansione completa tempo di tutti i canali che utilizzano 40 abita MHz. CleanAir è supportato in modalità monitor insieme a tutte le altre applicazioni in modalità correnti del monitor, tra cui WIPS adattivi e la valorizzazione posizione. In una configurazione radio dual questo assicura che tutte le bande canali sono regolarmente sottoposti a scansione. CleanAir abilitato MMAPs possono essere implementate come parte di una distribuzione diffusa di CleanAir permesso LMAPs per fornire copertura aggiuntiva in 2,4 e 5 GHz, o come soluzione standalone per sovrapposizione funzionalità CleanAir in una distribuzione non-CleanAir AP esistente. In uno scenario come detto sopra dove la sicurezza è un fattore primario, è probabile che Adaptive WIPs sarebbe anche un requisito. Questo è supportato in concomitanza con CleanAir sullo stesso MMAP. Ci sono alcune differenze distinte nel modo in cui alcune delle funzionalità sono supportate durante la distribuzione di come una soluzione di sovrapposizione. Thisis coperto in discussione modelli di implementazione in questo documento. Spectrum Expert Connect modalità SE Connect (opzionale) Un SE Connect AP è configurato come un sensore di spettro dedicato che permette il collegamento dell'applicazione Cisco Spectrum Expert in esecuzione su un host locale per utilizzare il CleanAir AP come sensore spettro remoto per l'applicazione locale. Il collegamento tra Spectrum Expert e il telecomando AP bypassa il controller sul piano dati. L'AP rimane in contatto con il controller sul piano di controllo. Questa modalità consente la visualizzazione dei dati grezzi dello spettro, come trame FFT e misure dettagliate. Tutte le funzionalità del sistema CleanAir è sospeso mentre l'AP è in questa modalità, e nessun client sono serviti. Questa modalità è destinata esclusivamente la risoluzione dei problemi a distanza. L'applicazione Spectrum Expert è un'applicazione di MS Windows che si connette al AP via una sessione TCP. Esso può essere supportato in VMWare. Nel CleanAir è stato introdotto il concetto di qualità dell'aria. La qualità dell'aria è una misura della percentuale di tempo che lo spettro in un particolare contenitore osservata (radio, AP, Band, Piano, Edificio) è disponibile per il traffico Wi-Fi. AQ è funzione dell'indice di gravità, che è calcolato per ciascuna fonte di interferenza classificate. L'indice di gravità non valuta ogni dispositivi Wi-Fi sulle caratteristiche in aria e calcola la percentuale di tempo lo spettro non è disponibile per la connessione Wi-Fi con questo dispositivo presente. La qualità dell'aria è un prodotto degli indici di gravità di tutte le fonti di disturbo classificati. Questo viene poi riportato come la complessiva qualità dell'aria da radiochannel, band, o RF dominio di propagazione (piano, edificio) e rappresenta il costo totale contro disponibile tempo di trasmissione di tutte le fonti non Wi-Fi. Tutto ciò che è rimasto è teoricamente a disposizione della rete Wi-Fi per il traffico. Questo è teorico perché c'è tutta una scienza dietro misurare l'efficienza del traffico Wi-Fi, e questo va oltre lo scopo di questo documento. Tuttavia, sapendo che l'interferenza è o non è un impatto che la scienza è un obiettivo chiave se il vostro piano è successo per identificare e mitigare i punti di dolore. Ciò che rende una fonte di gravi interferenze Cosa determina se isor non è un problema Come posso utilizzare queste informazioni per gestire la mia rete Queste domande sono discussi in questo documento. In termini più semplici, non utilizzo Wi-Fi si riduce a come spesso un'altra radio sta usando il mio spettro reti (Duty Cycle) e quanto forte sia in relazione ai miei radio (RSSIlocation). Energia nel canale che viene visto da un 802.11 un'interfaccia cerca di accedere al canale viene percepito come un canale occupato se è superiore a una certa soglia di energia. Ciò è determinato da Clear Channel Assessment (CCA). Wi-Fi utilizza un ascolto prima di metodo di accesso canale vocale per contesa connessione PHY. Questo è per CSMA-CA (-CAcollision evitamento). L'RSSI della interferente determina se può essere ascoltato al di sopra della soglia di CCA. Il ciclo di lavoro è la puntuale di un trasmettitore. Questo determina come persistente un'energia è nel canale. Il ciclo di dovere più alto è il più spesso il canale è bloccato. Semplice gravità può essere dimostrata in questo modo quindi utilizzando rigorosamente l'RSSI e il duty cycle. A scopo illustrativo, un dispositivo con 100 duty cycle è assunto. Figura 5: Come segnale di interferenza diminuisce - aumenta AQI nel grafico di questa figura si può vedere che, come la potenza del interferenza del segnale diminuisce, il conseguente aumento AQI. Tecnicamente, non appena il segnale scende sotto -65 dBm, l'AP non è più bloccata. Si ha bisogno di pensare intestano l'impatto che questo ha sui clienti nella cella. 100 duty cycle (DC) assicura costante interruzione di segnali client con SNR insufficiente in presenza di rumore. AQ aumenta rapidamente una volta la potenza del segnale scende sotto -78 dBm. Finora ci sono due dei tre maggiori impatti di interferenza definiti nella gravità basata sulla qualità dell'aria metrica: interferenza è semplice se si guarda 100 DC. Questo è il tipo di segnale più spesso utilizzato nelle manifestazioni della effetto di interferenza. È facile vedere in uno spettrogramma, e ha un effetto drammatico sul canale Wi-Fi. Questo accade nel mondo reale anche, ad esempio nelle videocamere analogiche, rilevatori di movimento, apparecchiature di telemetria, i segnali TDM e telefono cordless anziani. Ci sono molti segnali che non sono 100 DC. In realtà, un sacco di interferenza che si incontra è interferenza di questo tipo: variabile minima. Qui diventa un po 'più difficile da chiamare la gravità. Esempi di interferenza di questo tipo sono Bluetooth, telefoni cordless, altoparlanti wireless, dispositivi di telemetria, più vecchio ingranaggio 802.11FH e così via. Per esempio, un unico auricolare Bluetooth non fa molti danni in un ambiente Wi-Fi. Tuttavia, tre di questi con propagazione sovrapposizione può scollegare un telefono Wi-Fi se attraversato. Oltre al CCA, ci sono disposizioni in 802.11 specifiche, come la finestra di contesa, che è necessaria per ospitare tempo di trasmissione di protocolli di base differenti. Poi a questo si aggiunge vari meccanismi QoS. Tutte queste riserve dei media sono utilizzati da applicazioni diverse per massimizzare l'efficienza e ridurre al minimo tempo di trasmissione collisioni. Questo può creare confusione. Tuttavia, poiché tutte le interfacce in onda partecipano e sono d'accordo sullo stesso gruppo di norme, funziona molto bene. Cosa accade a questo caos ordinato quando si introduce una energia molto specifico che non capisce i meccanismi di contesa o per quella materia non ha nemmeno partecipare a CSMA-CA Beh, caos in realtà, in misura maggiore o minore. Dipende da come occupato il mezzo è quando la si verificano interferenze. Figura 6: simili ma diversi cicli Duty canale si possono avere due segnali identici in termini di ciclo di dovere come misurata nel canale e l'ampiezza, ma hanno due totalmente diversi livelli di interferenza sperimentato su una rete Wi-Fi. Un impulso breve veloce ripetizione può essere più devastante per la connessione Wi-Fi che un relativamente lento grasso ripetere. Guardate un jammer RF, che chiude in modo efficace lungo un canale Wi-Fi e registra molto poco duty cycle. Per fare un buon lavoro di valutazione, è necessaria una migliore comprensione della intervallo minimo le interferenze introdotte. L'intervallo minimo le interferenze spiega il fatto che nel canale impulsi interrompono l'attività Wi-Fi per un certo periodo più lungo rispetto ai loro durata effettiva, a causa di tre effetti: se già il conto alla rovescia, i dispositivi Wi-Fi deve attendere un periodo DIFS aggiuntivo dopo l'interferenza impulso. Questo caso è tipico per reti fortemente caricati, in cui l'interferenza inizia prima che il contatore back-off Wi-Fis ha contato fino a zero. Se arriva un nuovo pacchetto da trasmettere metà interferenza, il dispositivo Wi-Fi deve inoltre fare marcia indietro con un valore casuale compreso tra zero e CWmin. Questo caso è tipico per reti carichi leggeri, in cui l'interferenza inizia prima che il pacchetto Wi-Fi raggiunge la MAC per la trasmissione. Se il dispositivo Wi-Fi è già trasmettendo un pacchetto quando lo scoppio interferenza arriva, l'intero pacchetto deve essere ritrasmesso con il valore immediatamente superiore della CW, fino a CWmax. Questo caso è tipico se l'interferenza inizia il suo secondo, in parte attraverso una connessione Wi-Fi pacchetto esistente. Se il tempo indietro trascorre senza ritrasmissione di successo, allora la prossima marcia indietro è il doppio del precedente. Questo continua con esito negativo trasmissione fino a CWmax viene raggiunto o TTL viene superata per il telaio. Figura 7 - Per 802.11bg CWmin 31, per 802.11a CWmin è 15, entrambi hanno CWmax di 1023 in una vera e propria rete Wi-Fi, è difficile stimare la durata media di questi tre effetti, perché sono le funzioni del numero di dispositivi nel BSS, si sovrappongono BSS, l'attività del dispositivo, le lunghezze dei pacchetti, sostenuta protocolli velocità, QoS, e l'attività presenti. Pertanto, la cosa migliore è creare una metrica che rimane costante come punto di riferimento. Questo è ciò che fa di gravità. Si misura l'impatto di un singolo interferente contro una rete teorica, e mantiene un rapporto costante di gravità indipendentemente l'utilizzazione sottostante della rete. Questo ci dà un punto relativo a guardare attraverso infrastrutture di rete. La risposta alla domanda di quanto non interferenza Wi-Fi è male è soggettivo. Nelle reti con poco carico è del tutto possibile avere livelli di non interferenza Wi-Fi che passano inosservati da parte degli utenti e amministratori. Questo è ciò che porta a problemi alla fine. La natura delle reti wireless è diventare più occupato nel tempo. Il successo porta alla adozione organizzativa più veloce, e per nuove applicazioni di essere commesso. If there is interference present from day one, it is quite likely that the network have a problem with this when it becomes busy enough. When this happens it is difficult for people to believe that something that has been fine seemingly all along is the culprit. How do we use CleanAirs Air Quality and Severity metrics AQ is used to develop and monitor a baseline spectrum measurement and alert on changes indicating a performance impact. You can also use it for long term trend assessment through reporting. Severity is used to evaluate interference impact potential and prioritize individual devices for mitigation. Non Wi-Fi transmitters are less than friendly when it comes to unique characteristics that can be used to identify them. That is essentially what made the Cisco Spectrum Expert solution so revolutionary. Now with CleanAir there are multiple APs that potentially all hears the same interference at the same time. Correlating these reports to isolate unique instances is a challenge that had to be solved to provide advanced features, such as location of interference devices, as well as an accurate count. Enter the Pseudo MAC or PMAC. Because an analog video device does not have a MAC address or, in several cases, any other identifying digital tag an algorithm had to be created to identify unique devices being reported from multiple sources. A PMAC is calculated as part of the device classification and included in the interference device record (IDR). Each AP generates the PMAC independently, and while it is not identical for each report (at a minimum the measured RSSI of the device is likely different at each AP), it is similar. The function of comparing and evaluating PMACs is called merging. The PMAC is not exposed on customer interfaces. Only the results of merging are available in the form of a cluster ID. This merging is discussed next. Figure 8: Raw Detection of Interference In this graphic you can see several APs all reporting DECT, such as Phone energy. However, the APs in this graphic are actually reporting on the presence of two distinct DECT, such as Phone sources. Before the assignment of a PMAC and subsequent merging, there is only the device classification, which can be misleading. PMAC gives us a way to identify individual interference sources, even if they do not have any logical information that can be used such as an address. There are several APs all reporting a similar device. For each reporting AP, the PMAC is assigned to the classified signal. The next step is to combine the PMACs that are likely the same source device to a single report for the system. This is what merging does, consolidating multiple reports to a single event. Merging uses spatial proximity of the reporting APs. If there are six similar IDRs with five from APs on the same floor, and another one from a building a mile away, it is unlikely this is the same interferer. Once a proximity is established, a probability calculation is run to further match the distinct IDRs that belong and the result is assigned to a cluster. A cluster represents the record of that interference device and captures the individual APs that are reporting on it. Subsequent IDR reports or updates on the same device follow the same process and instead of creating a new cluster are matched to an existing one. In a cluster report, one AP is designated as the Cluster Center. This is the AP that hears the interference the loudest. Figure 9: After the PMAC Merge - APs hearing the same physical device are identified The merging algorithm runs on every CleanAir enabled WLC. A WLC performs the merge function for all IDRs from APs that are physically associated to it. All IDRs and resulting merged clusters are forwarded to an MSE, if it exists in the system. Systems with more than one WLC require an MSE to provide merging services. The MSE performs a more advanced merging function that seeks to merge clusters reported from different WLCs and extract location information to be reported to the WCS. Why do we need an MSE to merge IDRs across multiple WLCs Because a single WLC only knows the neighbors for the APs physically associated to it. RF Proximity cannot be determined for IDRs coming from APs located on different controllers unless you have a full system view. The MSE has this view. How physical proximity is determined differs, depending on how you implement CleanAir as well. For LMAP pervasive implementations, the APs all participate in Neighbor Discovery, so it is an easy matter to consult the RF neighbor list and determine spatial relationships for IDRs. In an MMAP overlay model you do not have this information. MMAPs are passive devices and do not transmit neighbor messages. Therefore, establishing the spatial relationship of one MMAP to another MMAP has to be done using X and Y coordinates from a system map. In order to do this, you also need the MSE that knows about the system map and can provide merging functions. More detail on the different modes of operation as well as practical deployment advice is covered in the deployment models section. Deploying APs in mixed mode LMAP CleanAir APs with an overlay of MMAP CleanAir APs is the best approach to high accuracy and total coverage. You can use the neighbor list created by the received neighbor messages for the MMAP as part of the merging information. In other words, if you have a PMAC from a LMAP AP and a PMAC from a MMAP, and the MMAP shows the LMAP AP as a neighbor, then the two can be merged with a high degree of confidence. This is not possible with CleanAir MMAPs deployed within legacy standard APs because those APs do not produce IDRs to compare with the merge process. The MSE and the X and Y references are still needed. Determining the location of a radio transmitter in theory is a fairly straightforward process. You sample the received signal from multiple locations and you triangulate based on the received signal strength. On a Wi-Fi network clients are located and Wi-Fi RFID tags with good results as long as there is a sufficient density of receivers and adequate signal to noise ratio. Wi-Fi clients and tags send probes on all supported channels regularly. This ensures that all APs within range hear the client or TAG regardless of the channel it is serving. This provides a lot of information to work with. We also know that the device (tag or client) subscribes to a specification that governs how it operates. Therefore, you can be certain that the device is using an omni-directional antenna and has a predictable initial transmit power. Wi-Fi devices also contain logical information that identifies it as a unique signal source (MAC address). Note: There is no guarantee of accuracy for location of non - Wi-Fi devices. Accuracy can be quite good and useful. However, there are a lot of variables in the world of consumer electronics and unintentional electrical interference. Any expectation of accuracy that is derived from current Client or Tag location accuracy models does not apply to non - Wi-Fi location and CleanAir features. Non Wi-Fi interference sources pose a special opportunity to get creative. For instance, what if the signal you are trying to locate is a narrow video signal (1 MHz) that is only affecting one channel In 2.4 GHz this probably works fine because most organizations have sufficient density to ensure that at least three APs on the same channel will hear it. However, in 5 GHz this is more difficult since most non-Wi-Fi devices only operate in the 5.8 GHz band. If RRM has DCA enabled with country channels, the number of APs actually assigned in 5.8 GHz declines because its goal is to spread out channel re-use and make use of open spectrum. This sounds bad, but remember if you are not detecting it, then it is not interfering with anything. Therefore, is really not a problem from a standpoint of interference. This is however an issue if your deployment concerns extend to security. In order to gain proper coverage you require some MMAP APs in addition to the LMAP APs to ensure full spectral coverage within the band. If your only concern is securing the operating space you are using, then you can also limit the channels available in DCA and force increased density in the channel ranges you wish to cover. The RF parameters of non - Wi-Fi devices can and do vary widely. An estimate has to be made based on the type of device that is being detected. The starting RSSI of the signal source needs to be known for good accuracy. You can estimate this based on experience, but if the device has a directional antenna the calculations will be off. If the device runs on battery power and experiences voltage sags or peaks as it operates, this will change how the system sees it. A different manufacturers implementation of a known product might not meet the expectations of the system. This will affect the calculations. Fortunately, Cisco has some experience in this area, and non-Wi-Fi device location actually works quite well. The point that needs to be made is that the accuracy of a non - Wi-Fi device location has a lot of variables to consider, accuracy increases with power, duty cycle, and number of channels hearing the device. This is good news because higher power, higher duty cycle, devices that impact multiple channels is generally what is considered to be severe as far as interference to the network goes. Cisco CleanAir APs, first and foremost, are access points. What this means is that there is nothing inherently different about deploying these APs over deploying any other currently shipping AP. What has changed is the introduction of CleanAir. This is a passive technology that does not impact the operation of the Wi-Fi network in any way, other than the noted mitigation strategies of ED-RRM and PDA. These are only available in a Greenfield installation and configured off by default. This section will deal with the sensitivity, density and the coverage requirements for good CleanAir functionality. These are not all that different from other established technology models such as a Voice, Video, or Location deployment. Valid deployment models for CleanAir products and feature functionality. Table 5: CleanAir Deployment Models vs Features CleanAir is a passive technology. All it does is hear things. Because an AP hears a lot farther than it can effectively talk this makes it a simple task to do a correct design in a Greenfield environment. Understanding how well CleanAir hears, and how classification and detection works, will give you the answers you need for any configuration of CleanAir. CleanAir depends on detection. The detection sensitivity is more generous than Wi-Fi throughput requirements with a requirement of 10 dB SNR for all classifiers, and many operable down to 5 dB. In most conceivable deployments where coverage is pervasive, there should not be any issues in hearing and detecting interference within the network infrastructure. How this breaks down is simple. In a network where the average AP power is at or between 5-11 dBm (power levels 3-5) then a class 3 (1 mW0 dBm) Bluetooth device should be detected down to -85 dBm. Raising the noise floor above this level creates a slight degradation in detection dB for dB. For design purposes it is worth adding a buffer zone by setting the minimum design goal to say -80. This will provide sufficient overlap in most conceivable situations. Note: Bluetooth is a good classifier to design for because it represents the bottom end power wise in devices you would be looking for. Anything lower generally does not even register on a Wi-Fi network. It is also handy (and readily available) to test with because it is a frequency hopper and will be seen by every AP, regardless of mode or channel in 2.4 GHz. It is important to understand your interference source. For instance Bluetooth. Here are multiple flavors of this in the market presently and the radios and specification have continued to evolve as most technologies do over time. A Bluetooth headset that you would use for your cell phone is most likely a class3 or class2 device. This operates on low power and makes ample use of adaptive power profiles, which extends battery life and reduces interference. A Bluetooth headset will transmit frequently on paging (Discovery mode) until associated. Then it will go dormant until needed in order to conserve power. CleanAir will only detect an active BT transmission. No RF, then nothing to detect. Therefore, if you are going to test with something, make sure it is transmitting. Play some music across it, but force it to transmit. Spectrum Expert Connect is a handy way to verify if something is, or is not transmitting and will end a lot of potential confusion. CleanAir was designed to compliment what is largely considered a normal density implementation. This definition of Normal continues to evolve. For instance, just five years ago 300 APs on the same system was considered a large implementation. In a lot of the world it still is. Numbers of 3,000-5,000 APs with many hundreds of them sharing direct knowledge through RF propagation are routinely seen. What is important to understand is: CleanAir LMAP supports the assigned channel only . Band Coverage is implemented by ensuring that channels are covered. The CleanAir AP can hear very well, and the active cell boundary is not the limit. For Location solutions, the RSSI cutoff value is -75 dBm. A minimum of three quality measurements is required for Location Resolution. In most deployments it is hard to image a coverage area that will not have at least three APs within ear shot on the same channel in 2.4 GHz. If there are not, then location resolution suffers. Add a Monitor Mode AP and use the guidelines. Remember that the location cutoff is -75 dBm corrects this because an MMAP listens to all channels. In locations where there is minimal density location resolution is likely not supported. But, you are protecting the active user channel extremely well. Also in such an area, you are generally not talking about a lot of space so locating an interference source does not pose the same problem as a multifloor dwelling. Deployment considerations come down to planning the network for desired capacity, and ensuring that you have the correct components and network paths in place to support CleanAir functions. RF proximity and the importance of RF Neighbor Relations cannot be understated. Make sure to understand PMAC and the merging process well. If a network does not have a good RF design, the neighbor relations is generally affected. This affects CleanAir performance. If you plan to install CleanAir MMAPs as an overlay to an existing network there are some limitations you need to keep in mind. CleanAir 7.0 software is supported on all of Ciscos shipping controllers. Each model controller supports the maximum rated AP capacity with CleanAir LMAPs. There are limits in the number of MMAPs that can be supported. The maximum number of MMAPs is a function of memory. The controller must store AQ details for each monitored channel. An LMAP requires two channels storage of AQ information. However, an MMAP is passively scanning and the channel data can be 25 channels per AP. Use the table below for design guidance. Always refer to the current release documentation for current information by release. Table 6: MMAP limits on WLCs Note: The numbers quoted for clusters (merged interference reports) and device records (individual IDR Reports before merging) are generous and highly unlikely to be exceeded in even the worst environments. Suppose you simply want to deploy CleanAir as a sensor network to monitor and be alerted about non - Wi-Fi interference. How many Monitor Mode APs (MMAPs) do you need The answer is generally 1-5 MMAP to LMAP radios. This of course depends on your coverage model. How much coverage do you get with an MMAP AP Quite a bit actually since you are strictly listening. The coverage area is far greater than if you also had to communicate and transmit. How about you visualize this on a map (you can use any planning tool available following a similar procedure as described below) If you have WCS and already have the system maps built, then this is an easy exercise. Use the planning mode in theWCS maps. Select Monitor gt Maps. Select the map you want to work with. In the right hand corner of the WCS screen use the radio button to select Planning Mode, then click go. Figure 10: WCS Planning mode Select the AP type. Use the default antennas for internal or change to match your deployment: 1 AP TX Power for both 5 GHz and 2.4 GHz is 1 dBm Class3 BT 1 mW Select ADD AP at the bottom. Figure 11: Add AP in WCS planner Move the AP to place on your map and select apply. The heat map populates. Choose -80 dBm for the RSSI cutoff at the top of the map, the map re-draws if this is a change. Here is what your CleanAir MMAP covers for 1 dBm out to -80 dBm. These results show a cell with a radius of 70 feet or 15,000 ft2 of coverage. Figure 12: Example Coverage of CleanAir MMAP using 1 dBm power and -80 dBm cutoff for coverage Note: Keep in mind that this is a predictive analysis. The accuracy of this analysis depends directly on the accuracy of the maps used to create it. It is beyond the scope of this document to provide a step by step instruction on how to edit maps within a WCS. A good question you want to ask is are these MMAPs going to be deployed strictly for CleanAir Or, are you going to take advantage of the many benefits that can be derived from the inclusion of monitoring APs in your network All of these applications work with CleanAir enabled APs. For Adaptive wIPS, refer to the Cisco Adaptive wIPS Deployment Guide as the coverage recommendation of Adaptive wIPS are similar, but dependent on your goals and customers needs. For location services ensure that you review and understand the deployment requirements for your technology. All of these solutions are complimentary with CleanAir design goals. Why should I not mix CleanAir LMAP and Legacy LMAP APs in the same physical area This question pertains to this use case: I currently have non CleanAir APs deployed (1130,1240, 1250, 1140) in local mode. I want to add just a few CleanAir APs to increase my coveragedensity. Why cant I just add some APs and get all the CleanAir features This is not recommended because CleanAir LMAPs only monitor the serving channel and all CleanAir features rely on measurement density for quality. This installation would result in indiscriminate coverage of the band. You could well end up with a channel (or several) that has no CleanAir coverage at all. However with the base installation, you would be using all of the channels available. Assuming RRM is in control (recommended) it is entirely possible that all of the CleanAir APs could be assigned to the same channel in a normal installation. You spread them out to try to get the best spatial coverage possible, and that actually increases the odds of this. You certainly can deploy a few CleanAir APs in with an existing installation. It is an AP and would function fine from a client and coverage standpoint. CleanAir functionality would be compromised and there is no way to really guarantee what the system would or would not tell you regarding your spectrum. There are far too many options in density and coverage which can be introduced to predict. What would work AQ would be valid for the reporting radio only. This means it is only relevant for the channel that it is serving, and this could change at any time. Interference alerts and zone of impact would be valid. However, any location derived would be suspect. Best to leave that out all together and assume closest AP resolution. Mitigation strategies would be ill-advised to operate because most of the APs in the deployment would not operate the same way. You would be able to use the AP to look at spectrum from Spectrum Connect. You would also have the option to temporarily switch to monitor mode at any time in order to perform a full scan of the environment. While there are some benefits, it is important to understand the pitfalls and adjust expectations accordingly. It is not recommended, and issues arising from this type of deployment are not supportable based on this deployment model. A better option if your budget does not support adding APs that do not serve client traffic (MMAP) is to collect enough CleanAir APs to deploy together in a single area. Any area that can be enclosed on a map area can contain a Greenfield CleanAir deployment with full feature support. The only caveat on this would be location. You still need enough density for location. While it is not advisable to mix legacy APs and CleanAir APs operating in local mode in the same deployment area, what about running both on the same WLC This is perfectly fine. Configurations for CleanAir are only applicable to APs that support CleanAir. For instance, in the RRM configuration parameters for both 802.11an and 802.11bgn you see both ED-RRM and PDA configurations for RRM. One might consider that these would be bad if applied to an AP that was not a CleanAir capable AP. However, even though these features do interact with RRM, they can only be triggered by a CleanAir event and are tracked to the AP that triggers them. There is no chance that a non - CleanAir AP has these configurations applied to them, even though the configuration applies to the whole RF group. This raises another important point. While CleanAir configurations on a 7.0 or later controller are effective for any CleanAir AP that attaches to that controller, ED-RRM and PDA are still RRM configurations. Implementation of CleanAir draws on many of the architecture elements present within the CUWN. It has been designed to fortify and add functionality to every system component, and draws on information that is already present top enhance usability and tightly integrate the features. This is the overall breakdown classified into license tiers. Notice that it is not necessary to have a WCS and or the MSE in the system to get good functionality from the system. The MIBs are available on the controller and are open to those who wish to integrate these features into an existing management system. For a basic CleanAir system, the requirements are a CleanAir AP and a WLC that runs version 7.0 or later code. This provides both a CLI and the WLC GUI for customer interface and all CURRENT data is displayed, including interference sources reported by band and the SE connect feature. Security Alerts (Interference sources designated as a security concern) are merged before triggering the SNMP trap. As previously stated though, WLC merging is limited to the view of just the APs associated to that controller. There is no historical support of trend analysis supported directly from the WLC interfaces. Adding a BASIC WCS and managing the controller adds trending support for AQ and alarms. You receive historical AQ reporting, threshold alerts through SNMP, RRM Dashboard support, Security alert support, and many other benefits including the client troubleshooting tool. What you do not get is Interference history and location. This is stored in the MSE. Note: Adding an MSE to the WCS for location requires both a WCS plus license and Context Aware feature licenses for the MSE. Adding an MSE and location solution to the network supports the historical IDR reporting as well as location based functions. In order to add this to an existing CUWN solution, you require a plus license on the WCS, and CAS or Context Aware licenses for the location targets. 1 Interferer 1 CAS license Interferers are managed through context aware and an interference that is tracked in the system is the same as a client for purposes of licensing. There are many options on how to manage these licenses and what they are used for. On the WLC configuration you can limit which interference sources are tracked for location and reporting in the maps by selecting them from the controller gt Wireless gt 802.11ba gt CleanAir menu. Interference devices selected there are reported, and choosing to ignore them keeps them out of the location system and MSE. This is completely separate from what is actually happening at the AP. All classifiers are always detected at the AP level. This determines what isdone with an IDR report. If you use this to limit reporting, then it is reasonably safe because all energy is still seen at the AP and is captured in AQ reports. AQ reports break out the contributing interference sources by category. If you eliminate a category here to conserve licensing, it is still reported as a contributing factor in AQ and you are alerted if you exceed a threshold. Figure 13: WLC CleanAir configuration - reporting For instance, suppose the network you are installing is in a retail environment, and the map is cluttered with Bluetooth targets coming from headsets. You could eliminate this by de-selecting the Bluetooth Link. If at some time later Bluetooth became a problem, you would see this category rise in your AQ reporting and could re-enable at will. There is no interface reset required. You also have the element manager under the MSE configurations: WCS gt Mobility Services gt Your MSE gt Context Aware Service gt administration gt tracking Parameters. Figure 14: MSE Context Aware element manager This gives the user complete control to assess and manage what licenses are used for and how they are divided among target categories. Table 7: CleanAir Features matrix by CUWN Component The minimum required configuration for Cisco CleanAir is the Cisco CleanAir AP, and a WLC which runs version 7.0. With these two components you can view all of the information provided by CleanAir APs. You also get the mitigation features available with the addition of CleanAir APs and the extensions provided through RRM. This information is viewable via the CLI or the GUI. The focus is on the GUI in this section for brevity. WLC Air Quality and Interference Reports On the WLC you can view current AQ and Interference reports from the GUI menu. In order to view interference reports, there must be interference active as the report is for current conditions only Interference Device Report Select Monitor gt Cisco CleanAir gt 802.11a802.11b gt Interference Devices. All active interference devices being reported by CleanAir Radios are listed by RadioAP reporting. Details include AP Name, Radio Slot ID, Interference Type, Affected Channels, Detected Time, Severity, Duty Cycle, RSSI, Device ID and Cluster ID. Figure 15: Accessing WLC Interference Device Report Air Quality Report Air Quality is reported by Radiochannel. In the example below, AP0022.bd18.87c0 is in monitor mode and displays AQ for channels 1-11. Selecting the radio button at the end of any line allows the option of showing this information in the radio detail screen, which includes all information gathered by the CleanAir interface. Figure 16: WLC Interference Device Report CleanAir Configuration AQ and Device Traps control CleanAir allows you to determine both the threshold and types of traps that you receive. Configuration is by band: Wireless gt 802.11ba gt CleanAir. Figure 17: WLC CleanAir configuration You can enable and disable CleanAir for the entire controller, suppress the reporting of all interferers, and determine which interferers to report or ignore. Selecting specific interference devices to ignore is a useful feature. For instance you might not want to track all Bluetooth headsets because they are relatively low impact and you have a lot of them. Choosing to ignore these devices simply prevents it from being reported. The RF that comes from the devices is still calculated into the total AQ for the spectrum. EnableDisable (on by default) the AirQuality trap. AQI Alarm Threshold (1 to 100). When you set the AirQuality threshold for traps, this tells the WLC at what level you want to see a trap for AirQuality. The default threshold is 35, which is extremely high. For testing purposes setting this value to 85 or 90 proves more practical. In practice, the threshold is variable so you can tune it for your specific environment. Enable Interference for Security Alarm. When you add the WLC to a WCS system, you can select this check box to treat interference device traps as security Alarm traps. This allows you to select the types of devices that appear in the WCS alarm summary panel as a security trap. Dodo not trap device selection allows control over the types of devices that generates interferencesecurity trap messages. Lastly, the status of ED-RRM (Event Driven RRM) is displayed. Configuration for this feature is covered under the Event Driven RRM - EDRRM section later in this document. Rapid Update Mode - CleanAir Detail Selecting Wireless gt Access Points gt Radios gt 802.11ab shows all of the 802.11b or 802.11a radios attached to the WLC. Selecting the radio button at the end of the line allows you to see either the radio detail (traditional non CleanAir metrics of utilization, noise and the like) or CleanAir detail. Figure 18: Accessing CleanAir Detail Selecting CleanAir produces a graphic (default) display of all CleanAir information pertaining to that radio. The information displayed is now in Rapid Update Mode by default. This means it is being refreshed every 30 seconds from the AP instead of the 15 minute averaging period displayed in system level messaging. From top to bottom, all interferers being detected by that radio along with the interference parameters of Type, Affected Channels, Detection Time, Severity, Duty Cycle, RSSI, Device ID, and Cluster ID. Figure 19: CleanAir Radio Detail Page From this figure, the displayed charts include: Air Quality by Channel Non - Wi-Fi Channel Utilization Air Quality by Channel displays the Air Quality for the channel that is being monitored. Non Wi-Fi channel utilization shows the utilization that is directly attributable to the interference device being displayed. In other words, if you get rid of that device you regain that much spectrum for Wi-Fi applications to use. There are two categories that are introduced here under Air Quality details: Adjacent Off Channel Interference (AOCI)This is interference from a Wi-Fi device that is not on the reporting operating channel, but is overlapping the channel space. For channel 6, the report would identify interference attributable to an AP on channels 4, 5, 7, and 8. UnclassifiedThis is energy that is not attributable definitively to Wi-Fi or non - Wi-Fi sources. Fragments, collisions, things of this nature frames that are mangled beyond recognition. In CleanAir guesses must not be made. Interference power displays the receive power of the interferer at that AP. The CleanAir Detail page displays information for all monitored channels. The examples above are from a Monitor Mode (MMAP) AP. A local Mode AP would show the same detail, but only for the current served channel. CleanAir Enabled RRM There are two key Mitigation Features that are present with CleanAir. Both rely directly on information that can only be gathered by CleanAir. Event Driven RRM Event Driven RRM (ED-RRM) is a feature that allows an AP in distress to bypass normal RRM intervals and immediately change channels. A CleanAir AP is always monitoring AQ, and reports on this in 15 second intervals. AirQuality is a better metric than relying on normal Wi-Fi chip noise measurements because AirQuality only reports on Classified Interference devices. This makes AirQuality a reliable metric because it is known what is reported is not because of Wi-Fi energy (and hence not a transient normal spike). For ED-RRM a channel change only occurs if the Air Quality is sufficiently impacted. Because Air Quality can only be affected by a classified known to CleanAir non - Wi-Fi source of interference (or an adjacent overlapping Wi-Fi channel), the impact is understood: Not a Wi-Fi anomaly A crisis condition at this AP Crisis means that CCA is blocked. No clients or the AP can use the current channel. Under these conditions RRM would change the channel on the next DCA pass. However, that could be a few minutes away (up to ten minutes depending on when the last run was performed), or the user could have changed the default interval and it could be longer (selected an anchor time and interval for longer DCA operation). ED-RRM reacts very quickly (30 seconds) so the users that change with the AP are likely unaware of the crisis that was close. 30 -50 seconds is not long enough to call a help desk. The users that do not are in no worse shape than they would have been in the first place. In all cases the interference source was identified and the AP change reason logs that source, and the users that have poor roaming receives an answer as to why this change was made. The channel change is not random. It is picked based on device contention, thus it is an intelligent alternate choice. Once the channel is changed there is protection against triggering ED-RRM again in a hold down timer (60 seconds). The event channel is also marked in RRM DCA for the affected AP to prevent a return to the event channel (3 hours) in the event the interferer is an intermittent event and DCA does not see it immediately. In all cases the impact of the channel change is isolated to the affected AP. Suppose a hacker or someone of ill intent fires up a 2.4 GHz jammer and all channels are blocked. First off, all the users within the radius are out of business anyway. However, suppose ED-RRM triggers on the all APs that can see it. All APs change channels once, then hold for 60 seconds. The condition would be met again, so another change would fire with the condition still being met after 60 seconds. There would be no channels left to change to and ED-RRM activity would stop. A security alert would fire off on the jammer (default action) and you would need to provide a location (if with MSE) or nearest detecting AP. ED-RRM would log a major AQ event for all affected channels. The reason would be RF jammer. The event would be contained within the effected RF domain and well alerted. Now the next question that is generally asked, quotwhat if the hacker walks around with the jammer, would that not that cause all the APs to trigger ED-RRMquot. Sure you are going to trigger ED-RRM channel changes on all the APs that have ED-RRM enabled. However, as the jammer moves so does its effect and usability is restored as soon as it moves. It really does not matter because you have a hacker walking around with a jammer in their hand disconnecting users everywhere they go. This is a problem in itself. ED-RRM does not compound that issue. CleanAir on the other hand is also busy alerting, locating, and providing the location history of where they went and where they are. These are good things to know in such a case. Configuration is accessed under Wireless gt 802.11a802.11b gt RRM gt DCA gt Event Driven RRM . Figure 20: Event Driven RRM Configuration Note: Once ED-RRM is triggered on an APChannel the AP is prevented from returning to that channel for three hours. This is to prevent thrashing if the signal source is intermittent in nature. Persistent Device Avoidance Persistent Device Avoidance is another mitigation feature that is only possible with CleanAir APs. A device that operates periodically, such as a microwave oven, can introduce destructive levels of interference while it is operating. However, once it is no longer in use the air goes quiet again. Devices such as video cameras, outdoor bridge equipment, and microwave ovens are all examples of a type of device called persistent. These devices can operate continuously or periodically, but what they all have in common is that they do not move frequently. RRM of course sees levels of RF noise on a given channel. If the device is operating long enough RRM even moves an active AP off the channel that has interference. However, once the device goes quiet, it is likely that the original channel presents as the better choice once again. Because each CleanAir AP is a spectrum sensor the center of the interference source can be evaluated and located. Also, you can understand which APs are affected by a device that you know is there, and potentially operates and disrupts the network when it does. Persistent Device Avoidance allows us to log the existence of such interference and remember that it is there so you do not place an AP back on the same channel. Once a Persistent Device has been identified it is remembered for seven days. If it is not seen again then it is cleared from the system. Each time you see it, the clock starts over. Note: Persistent Device Avoidance information is remembered at the AP and Controller. Rebooting either re-sets the value. Configuration for Persistent Device Avoidance is located at Wireless gt 802.11a802.11b gt RRM gt DCA gt Avoid Devices . In order to see if a radio has logged a Persistent Device you can view the status at Wireless gt Access Points gt Radios gt 802.11ab gt . Select a radio. At the end of the line click the radio button and select CleanAir RRM. Figure 21: CleanAir Persistent Device Avoidance status Spectrum Expert Connect CleanAir APs can all support the Spectrum Expert connect mode. This mode places the APs radios into a dedicated scanning mode that can drive the Cisco Spectrum Expert application across a network. The Spectrum Expert console functions as if it had a local Spectrum Expert card installed. Note: A routable network path must exist between the Spectrum Expert host and the target AP. Ports 37540 and 37550 must be open to connect. The Protocol is TCP, and the AP is listening. Spectrum Expert connect mode is an enhanced monitor mode, and as such the AP does not serve clients while this mode is enabled. When you initiate the mode the AP reboots. When it re-joins the controller it is in Spectrum Connect mode and have generated a session key for use to connect the application. All that is required is Cisco Spectrum Expert 4.0 or later, and a routable network path between the application host and the target AP. In order to initiate the connection, start by changing the mode on from Wireless gt Access Points gt All APs . Figure 22: AP Mode Configuration Go to AP Mode, and select SE-Connect. Save the configuration. You receive two warning screens: one advising that SE-connect mode is not a client-serving mode, the second warning that the AP is rebooted. Once you have changed the mode and saved the configuration navigate to the Monitor gt Access Points screen. Monitor the AP status and reload. Once the AP rejoins and reloads navigate back to the AP configuration screen, you need the NSI Key for the session that is displayed there. You can copy and paste the NSI key for the inclusion in launching Spectrum Expert. Figure 23: NSI Key generated You need Cisco Spectrum Expert 4.0. Once installed, launch Spectrum Expert. On the initial splash screen you see a new option, Remote Sensor. Select Remote Sensor and paste in the NSI Key, and tell Spectrum Expert the IP address of the AP. Select which radio you wish to connect to and click OK. Figure 24: Cisco Spectrum Expert Sensor connect screen When you add a WCS to the feature mix you get more display options for CleanAir information. The WLC can display current information, but with WCS the ability to track, monitor, alert, and report historical AirQuality levels for all CleanAir APs is added. Also, the ability to correlate CleanAir information to other award winning dashboards within WCS allows the user to fully understand their spectrum like never before. WCS CleanAir Dashboard The home page has several elements added and is customizable by the user. Any of the elements displayed on the home page can be re-arranged to user preferences. That is beyond the scope of this discussion, but keep it in mind as you use the system. What is being presented here is simply the default view. Selecting the CleanAir tab takes you to the CleanAir information available on the system. Figure 25: WCS Home Page Note: The default settings for the page include a top 10 interferers report by band in the right hand corner. If you do not have an MSE, this report does not populate. You can edit this page and add or delete components to customize it to your liking. Figure 26: WCS CleanAir Dashboard Charts displayed on this page display the running historical averages and minimums for CleanAir spectrum events. The average AQ number is for the entire system as displayed here. The minimum AQ chart for example tracks, by band, the minimum reported AQ received from any specific radio on the system in any 15 minute reporting period. You can use the charts to quickly identify historical minimums. Figure 27: Minimum Air Quality history chart Selecting the Enlarge Chart button on the bottom right in any chart object produces a pop-up window with an enlarged view of the chart in question. A mouse hover in any chart produces a time and date stamp, and AQ level seen for the reporting period. Figure 28: Enlarged Minimum Air Quality Chart Knowledge of the date and time gives you the information that you need to search for the particular event, and gather additional details such as APs that registered the event and device types operating at that time. AQ threshold alarms are reported to the WCS as performance alarms. You can also view them through the Alarm Summary panel at the top of the home page. Figure 29: Alarm Summary panel Either Advanced Search or simply selecting performance category from the alarm summary panel (provided you have a performance alarm) yields a list of performance alarms that contain details about a particular AQ event that is below the configured threshold. Figure 30: Air Quality Threshold Alarms Selecting a particular event displays the detail related to that event including the date, time, and most importantly the reporting AP. Figure 31: Performance Alarm Detail Configurations for Air Quality Thresholds is located under Configure gt Controller, either from the WCS GUI or the Controller GUI. This can be used for all CleanAir Configurations. The best practice is to use the WCS once you have assigned a controller to it. In order to generate performance alarms, you can set the AQ threshold for a low threshold such as 90 or even 95 (remember that AQ is good at 100 and bad at 0). You need some interference to trigger it such as a microwave oven. Remember to put a cup of water in it first and run it for 3-5 minutes. Air Quality History Tracking Reports AirQuality is tracked on each CleanAir AP at the radio level. The WCS enables historical reports for monitoring and trending AQ in your infrastructure. Reports can be accessed by navigating to the report launchpad. Select Reports gt Report Launchpad. CleanAir reports are at the top of the list. You can choose to look at Air Quality vs Time or Worst Air Quality APs. Both reports should be useful in tracking how Air Quality changes over time and identifying areas that require some attention. Figure 32: Report Launchpad CleanAir Maps Monitor gt Maps Selecting Monitor gt Maps displays the maps configured for the system. Average and minimum AQ numbers are presented in hierarchical fashion corresponding to the container levels of campus, building, and floor. For instance, at the building level the AverageMinimum AQ is the average of all CleanAir APs contained in the building. The minimum is the lowest AQ reported by any single CleanAir AP. Looking at a floor level, the average AQ represents the average of all APs located on that floor and the minimum AQ is that of the single worst AQ from an AP on that floor. Figure 33: Maps main page - showing Air Quality Hierarchy Selecting a map for a given floor provides detail relevant to the selected floor. There are a lot of ways that you can view the information on the map. For instance, you can change the AP tags to display CleanAir information such as CleanAir Status (shows which APs are capable), minimum or average AQ values, or Average and Minimum values. The values are relevant to the band selected. Figure 34: AP Tags show lots of CleanAir information You can see the interferers that are being reported by each AP in several ways. Hover over the AP, select a radio, and select the show interferers hotlink. This produces a list of all Interference detected on that interface. Figure 35: Viewing Interference Devices detected on an AP Another interesting way to visualize the impact of interference on the map is to select the interference tag. Without the MSE, you cannot locate interference on the map. However, you can select show interference labels, which are labels with the interferers currently being detected is applied to all CleanAir radios. You can customize this to limit the number of interferers displayed. Selecting the hotlink in the tab allows you to zoom in to the individual interferer details, and all interferers are displayed. Note: CleanAir APs can track unlimited numbers of interferers. They only report on the top 10 ordered by severity, with preference being given to a security threat. Figure 36: Interference Tag being displayed on all CleanAir APs A useful way to visualize non - Wi-Fi interference and its effect is to view AQ as a heatmap on the map display. Do this by selecting heatmaps and selecting Air Quality. You can display the average or the minimum AQ. The map is rendered using the coverage patterns for each AP. Notice that the upper right corner of the map is white. No AQ is rendered there because the AP is in monitor mode and passive. Figure 37: Air Quality Heat Map CleanAir Enabled RRM Dashboard CleanAir allows you to see what is in our spectrum that is non - Wi-Fi. In other words, all those things that were considered just noise can now be broken down to understand if and how it is impacting your data network. RRM can and does mitigate noise by selecting a better channel. When this occurs the solution is generally better than it was, but you are still letting something that is not your data network occupy your spectrum. This reduces the overall spectrum available to your data and voice applications. Wired and Wireless networks differ in that on a wired network if you need more bandwidth you can install more switches, or ports, or Internet connections. The signals are all contained within the wire and do not interfere with one another. In a wireless network, however, there is a finite amount of spectrum available. Once used, you cannot simply add more. The CleanAir RRM Dashboard on the WCS allows you to understand what is going on in your spectrum by tracking non - Wi-Fi interference as well as Signal from our network, Interference from foreign networks and balancing all within the spectrum that is available. The solutions that RRM provides do not always seem optimal. However, there is often something that you cannot see which causes two APs to operate on the same channel. The RRM Dashboard is what we use to track events that affect the balance of spectrum and provide answers as to why something is the way it is. CleanAir information being integrated to this dashboard is a big step forward to total control of the spectrum. Figure 38: CleanAir RRM Channel Change reasons from RRM Dashboard Channel Change reasons now include several new categories which refine the old Noise category (anything that is not Wi-Fi is recognized as noise by Cisco and all other competitors): Noise (CleanAir) represents non - Wi-Fi energy in the spectrum as being a cause or a major contributor to a channel change. Persistent Non-WiFi interference indicates that a persistent interferer has been detected and logged on an AP, and the AP changed channels to avoid this interference. Major Air Quality Event is the reason for a channel change invoked by the Event Driven RRM feature. Other there is always energy present in the spectrum that is not demodulated as Wi-Fi, and cannot be classified as a known interference source. The reasons for this are many: the signals are too corrupted to separate, left over remnants from collisions is one possibility. Knowing that non-WiFi interference is affecting your network is a big advantage. Having your network know and act on this information is a big plus. Some interference you are able to mitigate and remove, some you do not (in the case of a neighbors emissions). Typically most organizations have interference at one level or another, and a lot of this interference is low level enough to not pose any real problems. However, the busier your network gets the more it needs an unaffected spectrum. CleanAir Enabled Security Dashboard Non-Wi-Fi devices can offer quite a challenge to wireless security. Having the ability to examine signals at the physical layer allows for much more granular security. Normal every day consumer wireless devices can and do bypass normal Wi-Fi security. Because all existing WIDsWIPs applications rely on Wi-Fi chipsets for detection, there has been no way to accurately identify these threats until now. For instance, it is possible to invert the data in a wireless signal so that it is 180 degrees out of phase from a normal Wi-Fi signal. Or, you could change the center frequency of the channel by a few kHz and as long as you had a client set to the same center frequency you would have a private channel that no other Wi-Fi chip could see or understand. All that is required is access to the HAL layer (many are available under GPL) for the chip and a little bit of skill. CleanAir is able to detect and understand what these signals are. In addition, CleanAir can detect and locate a PhyDOS attack such as RF Jamming. You can configure CleanAir to report any device that is classified as a security threat. This allows the user to determine what should and should not be transmitting within their facility. There are three ways to view these events. The most convenient is through the Alarm Summary panel located at the top of the WCS home page. A more detailed analysis can be gained by using the Security Dashboard tab on the main page. This is where all security related information on the system is displayed. CleanAir now has its own section within this dashboard allowing you to gain a full understanding of the security of your network from all wireless sources. Figure 39: Security Dashboard with CleanAr integration No matter where you view this information from, you have the detecting AP, the time and date of the event, and the current status to work with. With an MSE added you can run periodic reports on just CleanAir security events. Or, you can look at the location on the map and see the history of the event, even if it was moving. CleanAir enabled Client Troubleshooting Dashboard The client dashboard on the WCS home page is the one stop for all things for clients. Because interference often affects a client before it affects the AP (lower power, poorer antennas) a key thing to know when troubleshooting client performance issues is if non - Wi-Fi interference is a factor. CleanAir has been integrated to the Client Troubleshooting tool on the WCS for that reason. Access the client information in any way you choose from the dashboard, either by searching on a MAC address or user. Once you have the client displayed, select the Client Troubleshooting tool Icon to launch the Client Troubleshooting Dashboard. Figure 40: Client Troubleshooting Dashboard - with CleanAir The client tools provide a wealth of information about the clients status on the network. Select the CleanAir tab on the Monitor Client screen. If the AP that the client is currently associated to is reporting any interference, it is displayed here. Figure 41: CleanAir tab from Client Troubleshooting tool In this case, the interference being detected is a DECT like phone, and because the severity is only 1 (very low) it would be unlikely to cause a lot of trouble. However, a couple of Severity 1 devices can cause issues for a client. The Client Dashboard allows you to quickly rule out, as well as prove, issues in a logical fashion. The MSE adds a significant amount of information to CleanAir features. The MSE is responsible for all location calculations, which are much more intensive for non-Wi-Fi interference than for a Wi-Fi target. The reason for this is the range of conditions that location has to work with. There are a lot of non-Wi-Fi interferers in the world, and they all operate differently. Even among similar devices there can be great differences in signal strength or radiation patterns. The MSE is also who manages merging of devices that span multiple controllers. If you recall, a WLC can merge devices that APs reports, which it is managing. But, interference can be detected that is present on APs that are not all on the same controller. All of the features that MSE enhances are located only in the WCS. Once you have located an interference device on a map, there are several things that can be calculated and presented about how that interference interacts with your network. WCS CleanAir Dashboard with MSE Previously in this document, the CleanAir Dashboard and how the top 10 interferers per band would not be displayed without the MSE was discussed. With the MSE, these are now active because you have the interference device and location information from the MSEs contribution. Figure 42: MSE enabled CleanAir dashboard The upper right hand tables are now populated with the 10 most severe interference sources detected for each band: 802.11an and 802.11bgn. Figure 43: Worst Interference for 802.11an The information displayed is similar to that of the interference report from a specific AP. Interference ID this is the database record for the interference on the MSE Type the type of interferer being detected Status currently only displays Active interferers Severity the severity calculated for the device Affected Channels the channels that the device is being seen affecting Discovered last updated time stamps Floor the map location of the interference If you choose the floor location, it hotlinks you to the map display of the interference source directly where much more information is possible. Note: There is one other difference beyond having a location between information displayed about interferers over what you can see on the AP radio level directly. You might have noticed that there is no RSSI value for the interference. This is because the record as seen here is merged. It is the result of multiple APs reporting the device. The RSSI information is no longer relevant, nor would it be correct to display it because each AP sees the device at different signal strength. WCS Maps with CleanAir device location Choose the link at the end of the record in order to navigate directly to the map location of the interference device from the CleanAir dashboard. Figure 44: Interference located on the map Now locating the interference source on the map allows us to understand its relationship to everything else on the map. In order to product specific information about the device itself (see figure 36), pass a mouse over the interference Icon. Notice the detecting APs, this is the list of APs that currently hears this device. The cluster Center is the AP that is closest to the device. The last line shows the Zone of Impact. This is the radius that the interference device would be suspected of being disruptive. Figure 45: Interference Detail from Mouse Hover The Zone of Impact is only half the story though. It is important to remember that a device might have a long reach or large zone of impact. However, if the severity is low it might or might not matter at all. Zone of impact can be viewed on the map by selecting Interferers gt Zone of Impact from the map display menu. Now you can see the Zone of Impact (ZOI) on the map. ZOI is rendered as a circle around the detected device, and its opacity darkens with higher severity. This aids visualizing the impact of interference devices greatly. A small dark circle is much more of a concern than a large translucent circle. You can combine this information with any other map display or element that you choose. Double-clicking on any interference icon takes you to the detail record for that interference. Figure 46: MSE Interference Record Interferer details include a lot of information about the type of interferer that is being detected. In the upper right hand corner is the help field which tells about what this device is and how this particular type of device affects your network. Figure 47: Detailed Help Other workflow links within the detail record include: Show Interferers of this Type links to a filter to show other instances of this type of device Show Interferers affecting this band links to a filtered display of all same band interferers Floor links back to the map location for this device MSE links to the reporting MSE configuration Clustered by links to the controllers that performed the initial merge Detecting APs hot links to the reporting APs for use in viewing the interference directly from the AP details Interference Location History From the command window in the upper right corner of the record display you can select to view the location history of this interference device. Location History shows the position and all relevant data such as timedate and detecting APs of an interference device. This can be extremely useful in understanding where the interference has been detected and how it has behaved or impacted your network. This information is part of the permanent record of the interference in the MSE database. WCS Monitor Interference The contents of the MSE interferer database can be viewed directly from the WCS by selecting Monitor gt Interference. Figure 48: Monitor Interferers display The list is sorted by status by default. However, it can be sorted by any of the columns contained. You might notice that RSSI information on the interferer is missing. This is because these are merged records. Multiple APs hear a particular interference source. All of them hear it differently, so severity replaces RSSI. You can select any interference IDs in this list to display the same detailed record as was discussed above. Selecting the device type produces the help information that is contained within the record. Selecting the floor location takes you to the map location of the interference. You can select Advanced Search and query the Interferers database directly, then filter the results by multiple criteria. Figure 49: Advance Interference Search You can choose all interferers by ID, by Type (includes all classifiers), severity (range), Duty Cycle (range) or location (floor). You can select the time period, the status (ActiveInactive), select a specific band or even a channel. Save the search for future use if you like. There are two basic types of information generated by the CleanAir components within the system: Interference Device Reports and AirQuality. The controller maintains the AQ database for all attached radios and is responsible for generating threshold traps based on the users configurable thresholds. The MSE manages Interference Device Reports and merges multiple reports arriving from controllers and APs that span controllers into a single event, and locates within the infrastructure. The WCS displays information collected and processed by different components within the CUWN CleanAir system. Individual information elements can be viewed from the individual components as raw data, and the WCS is used to consolidate and display a system wide view and provide automation and work flow. CleanAir installation is a straightforward process. Here are some tips on how to validate the functionality for an initial installation. If you upgrade a current system or install a new system, the best order of operations to follow is Controller code, WCS code, then add MSE code to the mix. Validation at each stage is recommended. In order to enable CleanAir functionality in the system, you first need to enable this on the controller through Wireless gt 802.11ab gt CleanAir . Ensure CleanAir is enabled. Questo è disabilitato per default. Once enabled it takes 15 minutes for normal system propagation of Air Quality information because the default reporting interval is 15 minutes. However, you can see the results instantly at the CleanAir detail level on the radio. Monitor gt Access Points gt 802.11an or 802.11bn This displays all radios for a given band. CleanAir status is displayed in the CleanAir Admin Status and CleanAir Oper Status columns. Admin Status relates to the radio status for CleanAir should be enabled by default Oper Status relates to the state of CleanAir for the system this is what the enable command on the controller menu mentioned above controls The operational status cannot be up if the admin status for the radio is disabled. Assuming that you have an Enable for Admin Status, and Up for Operational Status, you can select to view the CleanAir details for a given radio using the radio button located at the end of the row. The selection of CleanAir for details places the radio into Rapid Update mode and provides instant (30 second) updates to Air Quality. If you get Air Quality then CleanAir works. You might or might not see interferers at this point. This depends if you have any active. As previously mentioned, you do not have Air Quality reports for up to 15 minutes displaying in the WCS gt CleanAir tab after initially enabling CleanAir. However, Air Quality reporting should be enabled by default and can be used to validate the installation at this point. In the CleanAir tab you do not have interferers reported in the worst 802.11ab categories without an MSE. You can test an individually interference trap by designating an interference source that you can easily demonstrate as a security threat in the CleanAir configuration dialogue: Configure gt controllers gt 802.11ab gt CleanAir. Figure 50: CleanAir configuration - Security Alarm Adding an interference source for a Security Alarm causes the controller to send a trap message on discovery. This is reflected in the CleanAir tab under the Recent Security-risk Interferers heading. Without the MSE present you do not have any functionality for Monitor gt Interference. This is driven purely by the MSE. There is nothing particularly special about adding an MSE to the CUWN for CleanAir support. Once added, there are some specific configurations you need to make. Ensure that you have synchronized both the system maps and controller before you enable CleanAir tracking parameters. On the WCS console, choose Services gt Mobility Services gt select your MSE gt Context Aware Service gt Administration gt Tracking Parameters . Choose Interferers to enable MSE interference tracking and reporting. Remember to save. Figure 51: MSE Context Aware interference configuration While in the Context Aware Services Administration menu, also visit History Parameters and enable Interferers here as well. Save your selection. Figure 52: Context Aware History Tracking Parameters Enabling these configurations signals the synchronized controller to start the flow of CleanAir IDR information to the MSE and initiates the MSE tracking and convergence processes. It is possible to get the MSE and a controller out of synchronization from a CleanAir perspective. This can happen during an upgrade of controller code when interference sources from multiple controllers might get bounced (deactivated, and re-activated). Simply disabling these configurations and re-enabling with a save forces the MSE to re-register with all synchronized WLCs. Then, the WLCs send fresh data to the MSE, effectively re-starting the processes of merging and tracking of interference sources. When you first add an MSE, you must synchronize the MSE with the network designs and WLCs that you wish for it to provide services for. Synchronization is heavily dependent on Time. You can validate synchronization and NMSP protocol functionality by going to Services gt Synchronization services gt Controllers. Figure 53: Controller - MSE Synchronization Status You see the sync status for each WLC you are synchronized with. A particularly useful tool is located under the MSE column heading NMSP Status. Selecting this tool provides a wealth of information about the state of the NMSP protocol, and can give you information on why a particular synchronization is not occurring. Figure 54: NMSP Protocol Status One of the more common issues experienced is that the time on the MSE and WLC are not the same. If this is the condition, it is displayed in this status screen. There are two cases: WLC Time is after the MSE timeThis synchronizes. But, there are potential errors when merging multiple WLCs information. WLC time is before the MSE timeThis does not allow synchronization because the events have not occurred yet according to the MSEs clock. A good practice is to use NTP services for all controllers and the MSE. Once you have the MSE synchronized and CleanAir enabled, you should be able to see Interference sources in the CleanAir tab under Worst 802.11ab interferers. You can also view them under Monitor gt Interference, which is a direct display of the MSE interference database. One last potential gotcha exists on the Monitor Interferers display. The initial page is filtered to only display interferers that have a severity greater than 5. Figure 55: WCS - Monitor Interferers display This is stated on the initial screen, but often goes overlooked when initializing and validating a new system. You can edit this to display all interference sources by simply making the severity value 0. There are many terms used in this document that are not familiar to a lot of users. Several of these terms come from Spectrum Analysis, some are not. Resolution Band Width (RBW), the minimum RBWThe minimum band width that can be accurately displayed. SAgE2 cards (including the 3500) all have 156 KHz minimum RBW on a 20 MHz dwell, and 78 KHz on a 40 MHz dwell. DwellA dwell is the amount of time the receiver spends listening to a particular frequency. All lightweight access points (LAPs) do off channel dwells in support of rogue detection and metrics gathering for RRM. Spectrum Analyzers do a series of dwells to cover a whole band with a receiver that only covers a portion of the band. DSPDigital Signal Processing SAgESpectrum Analysis Engine Duty CycleDuty Cycle is the active on time of a transmitter. If a transmitter is actively using a particular frequency, the only way another transmitter can use that frequency is to be louder than the first, and significantly louder at that. A SNR margin is needed to understand it. Fast Fourier Transform (FFT)For those interested in the math, google this. Essentially, FFT is used to quantify an analog signal and convert the output from the Time domain to the Frequency domain.
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