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Ex-major leaguer Manny Ramirez signe avec la ligue indie japonaise 9 janvier 2017 L'ancien ancien gardien de la LNM Manny Ramirez a accepté les conditions avec le pilier de base commence le processus de réassemblage pour la pagode de la période Nara 10 janvier 2017 NARA - A été réinstallé sur la base de pierre d'un œil Lisas sur Tokyo: FUCHU - Comment correctement verser une bière et avoir un enfant en toute sécurité 10 janvier 2017 Placez un verre sec dans votre paume gauche et soulevez votre main droite, l'ami de Parcs refuse de témoigner À l'épreuve de mise en accusation à Séoul 10 janvier 2017 SEOUL - Le président sud-coréen déçu par Park Geun-hyes, ancien amiCisco CleanAir - Guide de conception de réseau sans fil Cisco Unified Le SI est une technologie de base conçue pour gérer de manière proactive les défis d'un spectre sans fil partagé . Essentiellement, SI apporte des algorithmes d'identification de brouillage avancés similaires à ceux utilisés dans les militaires au monde des réseaux sans fil commerciaux. SI offre une visibilité à tous les utilisateurs du spectre partagé, à la fois les périphériques Wi-Fi et les interférences étrangères. Pour tous les périphériques qui fonctionnent dans la bande sans licence, SI vous dit: Qu'est-ce que c'est? Comment cela influe-t-il sur le réseau Wi-Fi? Cisco a pris la mesure audacieuse d'intégrer directement SI à la solution de silicium et d'infrastructure Wi-Fi. La solution intégrée, appelée Cisco CleanAir, signifie pour la première fois que le gestionnaire informatique WLAN est en mesure d'identifier et de localiser des sources d'interférences non-802.11, ce qui soulève la barre sur la facilité de gestion et la sécurité des réseaux sans fil. Plus important encore, une SI intégrée ouvre la voie à une nouvelle race de gestion des ressources radio (RRM). Contrairement aux solutions RRM précédentes qui ne pouvaient que comprendre et s'adapter à d'autres périphériques Wi-Fi, SI ouvre la voie à une solution de RRM de deuxième génération parfaitement consciente de tous les utilisateurs du spectre sans fil et capable d'optimiser les performances du visage De ces dispositifs variés. Le premier point important à prendre est celui du point de vue de la conception. Les points d'accès (APs) CleanAir sont juste les APs et les performances sont pratiquement identiques aux 1140 APs. Conception pour la couverture Wi-Fi est la même avec les deux. CleanAir ou processus d'identification d'interférences sont un processus passif. CleanAir est basé sur le récepteur, et pour que la classification fonctionne, la source doit être assez bruyante pour être reçue à 10 dB au-dessus du plancher de bruit. Si votre réseau est déployé de manière à ce que vos clients et AP puissent s'entendre, CleanAir peut entendre suffisamment bien pour vous alerter sur des interférences troublantes au sein de votre réseau. Les exigences de couverture pour CleanAir sont détaillées dans ce document. Il existe des cas particuliers en fonction de l'itinéraire de mise en œuvre CleanAir que vous choisissez finalement. La technologie a été conçue pour compléter les meilleures pratiques actuelles en matière de déploiement Wi-Fi. Cela inclut les modèles de déploiement d'autres technologies largement utilisées telles que les wIPS adaptatifs, la voix et les déploiements de localisation. Cisco vous recommande de connaître CAPWAP et Cisco Unified Wireless Network (CUWN). Les informations contenues dans ce document sont basées sur ces versions logicielles et matérielles: Les AP capables de CleanAir sont Aironet 3502e, 3501e, 3502i, et 3501i Cisco WLAN Controller (WLC) exécutant la version 7.0.98.0 Cisco Wireless Control System (WCS) exécutant la version 7.0.164.0 Moteur de services de mobilité Cisco (MSE) exécutant la version 7.0 Pour plus d'informations sur les conventions de documents, consultez les conventions techniques de Cisco. CleanAir est un système, pas une fonctionnalité. Les composants logiciels et matériels CleanAir permettent de mesurer avec précision la qualité des canaux Wi-Fi et d'identifier les sources non-Wi-Fi d'interférences de canaux. Cela ne peut pas être fait avec un chipset Wi-Fi standard. Afin de comprendre les objectifs de conception et les exigences pour une mise en œuvre réussie, il est nécessaire de comprendre comment CleanAir fonctionne à un niveau élevé. Pour ceux déjà familiarisés avec la technologie Ciscos Spectrum Expert, CleanAir est une étape évolutive naturelle. Mais, il s'agit d'une technologie totalement nouvelle dans la mesure où il s'agit d'une technologie d'analyse de spectre distribué entreprise. En tant que tel, il est similaire à Cisco Spectrum Expert à certains égards, mais très différent dans d'autres. Les composants, les fonctions et les fonctionnalités sont décrits dans ce document. Les nouveaux AP capables de CleanAir sont Aironet 3502e, 3501e, 3502i et 3501i. Le e désigne l'antenne externe, le I désigne l'antenne interne. Les deux sont des AP 802.11n de nouvelle génération entièrement fonctionnels et fonctionnent sur une alimentation 802.3af standard. Figure 1: Points forts C3502E et C3502I CleanAir Capable Le matériel d'analyse du spectre est directement intégré au chipset de la radio. Cette addition a ajouté plus de 500 portes logiques K au silicium radio et a fourni un couplage exceptionnellement proche des caractéristiques. Il ya beaucoup d'autres caractéristiques traditionnelles, qui ont été ajoutés ou améliorés avec ces radios. Mais, cela dépasse le cadre de ce document et ceux-ci ne sont pas couverts ici. Il suffit de dire que, tout seul sans CleanAir les AP série 3500 pack beaucoup de fonctionnalités et de performance dans un AP entreprise attrayante et robuste. L'architecture de base de Cisco CleanAir se compose de points d'accès Cisco CleanAir activés et d'un contrôleur WLAN Cisco (WLAN). Cisco Wireless Control System (WCS) et Mobility Services Engine (MSE) sont des composants optionnels du système. Afin de tirer pleinement parti de l'information fournie par le système CleanAir, le WCS et le MSE sont essentiels pour tirer le meilleur parti de CleanAir. Cela fournit des interfaces utilisateur pour des fonctionnalités de spectre avancées telles que des cartes historiques, des dispositifs d'interférence de suivi, des services de localisation et l'analyse d'impact. Un AP équipé de la technologie Cisco CleanAir recueille des informations sur les sources d'interférences non-Wi-Fi, les traite et les envoie au WLC. Le WLC fait partie intégrante du système CleanAir. Le WLC contrôle et configure les AP capables de CleanAir, collecte et traite les données de spectre et les fournit au WCS et au MSE. Le WLC fournit des interfaces utilisateur locales (GUI et CLI) pour configurer les fonctionnalités et services de base de CleanAir et afficher les informations actuelles sur le spectre. Cisco WCS fournit des interfaces utilisateur avancées pour CleanAir qui incluent l'activation et la configuration des fonctionnalités, des informations d'affichage consolidées, des enregistrements historiques de la qualité de l'air et des moteurs de rapports. Figure 2: Flux du système logique Le MSE de Cisco est nécessaire pour le localisation et le suivi historique des périphériques d'interférence et assure la coordination et la consolidation des rapports d'interférence sur plusieurs WLC. Remarque: Un seul WLC ne peut consolider les alertes de brouillage que pour les AP directement connectés. La coordination des rapports qui proviennent de points d'accès associés à différents contrôleurs nécessite la MSE qui a une vue du système de tous les AP CleanAir et WLCs. Le cœur du système CleanAir est le ASIC (Spectrum Analysis Engine) ASIC, l'analyseur de spectre sur puce. Cependant, il est bien plus qu'un simple analyseur de spectre. Au cœur d'un puissant moteur FFT de 256 points qui offre une incroyable 78 KHz RBW (Resolution Band Width, la résolution minimale qui peut être affichée) construite intentionnellement pouls et des moteurs de collecte de statistiques ainsi que le DSP Accelerated Vector Engine (DAvE). Le matériel SAgE fonctionne en parallèle avec le chipset Wi-Fi et traite près de l'information de débit de ligne. Tout cela permet une précision extrême et des échelles pour un grand nombre de sources d'interférences similaires, sans pénalité dans le débit du trafic utilisateur. Le chipset Wi-Fi est toujours en ligne. Les balayages SAgE sont effectués une fois par seconde. Si un préambule Wi-Fi est détecté, il est transmis directement au chipset et n'est pas affecté par le matériel SAgE parallèle. Aucun paquet n'est perdu pendant le balayage SAgE, SAgE est désactivé alors qu'un paquet Wi-Fi est traité via le récepteur. SAgE est très rapide et précis. Même dans un environnement occupé, il y a plus que suffisamment de temps de scan pour évaluer précisément l'environnement. Pourquoi est-ce que RBF est important Si vous devez compter et mesurer la différence entre plusieurs radios Bluetooth qui sautent avec des signaux étroits à 1600 hops par seconde, vous devez séparer différents hachages d'émetteurs dans votre échantillon si vous voulez savoir combien il y en a. Cela prend la résolution. Autrement, tout ressemblerait à une impulsion. SAgE le fait, et il le fait bien. En raison du DAvE et étant associé à la mémoire de bord, la capacité de traiter plusieurs échantillons en parallèle est là. Cela augmente la vitesse, ce qui vous permet de traiter le flux de données en temps quasi réel. Près de temps réel signifie qu'il ya un certain retard, mais il est si minime qu'il faut un ordinateur pour le mesurer. Les AP Cisco CleanAir produisent deux types d'informations de base pour le système CleanAir. Un IDR (rapport de périphérique d'interférence) est généré pour chaque source d'interférence classifiée. Les rapports AQI (Air Quality Index) sont générés toutes les 15 secondes et transmis à Cisco IOS reg pour la moyenne et la transmission éventuelle au contrôleur en fonction de l'intervalle configuré. La messagerie CleanAir est traitée sur le plan de contrôle dans deux nouveaux types de messages CAPWAP: configuration du spectre et données du spectre. Les formats pour ces messages sont listés ici: Données de spectre AP WLC Le rapport de périphérique d'interférence (IDR) est un rapport détaillé qui contient des informations sur un périphérique d'interférence classifié. Ce rapport est très semblable à l'information que l'on voit dans Cisco Spectrum Expert Active Devices, ou Devices View. Les IDR actifs peuvent être visualisés sur la GUI et la CLI du WLC pour toutes les radios CleanAir sur ce WLC. Les IDR sont transmis au MSE seulement. Il s'agit du format d'un rapport IDR: Tableau 1 - Rapport sur les périphériques d'interférence Remarque: Les sources de brouillage marquées comme Interféreurs de sécurité sont désignées par l'utilisateur et peuvent être configurées via Wireless gt 802.11abgn gt cleanair gt. Toute source d'interférence classée peut être choisie pour une alerte de sécurité. Ceci envoie un piège de sécurité au WCS ou à un autre récepteur de piège configuré en fonction du type de brouilleur sélectionné. Ce piège ne contient pas les mêmes informations qu'un IDR. C'est simplement un moyen de déclencher une alarme sur la présence du brouilleur. Quand un brouilleur est désigné comme un problème de sécurité, il est marqué comme tel à l'AP et est toujours inclus dans les dix dispositifs qui sont signalés de l'AP indépendamment de la gravité. Les messages IDR sont envoyés en temps réel. Lors de la détection, l'IDR est marqué comme périphérique en haut. Si elle arrête un message de périphérique vers le bas est envoyé. Un message de mise à jour est envoyé toutes les 90 secondes depuis l'AP pour tous les périphériques en cours de suivi. Cela permet des mises à jour de statut des sources de brouillage suivies et une piste d'audit en cas de perte ou de perte d'un message en transit. La déclaration de la qualité de l'air (AQ) est disponible auprès de tout AP capable de spectre. La qualité de l'air est un nouveau concept avec CleanAir et représente une mesure de qualité du spectre disponible et indique la qualité de bande passante disponible pour le canal Wi-Fi. La qualité de l'air est une moyenne mobile qui évalue l'impact de tous les dispositifs d'interférence classifiés par rapport à un spectre théorique parfait. L'échelle est 0-100 avec 100 représentant Good. Les rapports AQ sont envoyés indépendamment pour chaque radio. Le rapport AQ le plus récent est visible sur l'interface graphique et l'interface de ligne de commande WLC. Les rapports AQ sont stockés sur le WLC et interrogés par intervalle régulier WCS. La valeur par défaut est 15 minutes (minimum) et peut être étendue à 60 minutes sur le WCS. Actuellement, la plupart des puces Wi-Fi standard évaluent le spectre en suivant l'ensemble de l'énergie de paquets qui peut être démodulée lors de la réception et de toute l'énergie de paquets qu'elle transmet. Toute énergie qui reste dans le spectre qui ne peut être démodulée ou représentée par l'activité RXTX est regroupée dans une catégorie appelée bruit. En réalité, beaucoup du bruit est en fait des restes de collisions, ou des paquets Wi-Fi qui tombent en dessous du seuil de réception pour la démodulation fiable. Avec CleanAir, une approche différente est prise. Toute l'énergie dans le spectre qui n'est certainement pas Wi-Fi est classé et comptabilisé. Nous pouvons également voir et comprendre l'énergie qui est 802.11 modulé et de classer l'énergie qui provient de Co-canal et les sources de canal adjacentes. Pour chaque dispositif classifié, un indice de gravité est calculé (voir la section Gravité), un entier positif compris entre 0 et 100, 100 étant le plus sévère. La gravité des interférences est ensuite soustraite de l'échelle AQ (à partir de 100 bonnes) pour générer l'AQ réelle pour un channelradio, AP, Floor, Building ou campus. AQ est alors une mesure de l'impact de tous les dispositifs classifiés sur l'environnement. Il existe deux modes de rapports AQ définis: la mise à jour normale et rapide. Le mode normal est le mode de rapport AQ par défaut. Le WCS ou le WLC récupère les rapports à une vitesse de mise à jour normale (la valeur par défaut est de 15 minutes). Le WCS informe le contrôleur de la période d'interrogation par défaut et le WLC demande à l'AP de modifier la période de calcul et la période de déclaration en conséquence. Lorsque l'utilisateur effectue des exercices pour surveiller gt Points d'accès gt et choisit une interface radio depuis le WCS ou le WLC, la radio sélectionnée est placée en mode de rapport de mise à jour rapide. Lorsqu'une demande est reçue, le contrôleur demande à l'AP de modifier temporairement la période de déclaration AQ par défaut à un taux de mise à jour rapide fixe (30 sec), ce qui permet une visibilité en temps quasi réel des changements AQ au niveau radio. L'état de rapport par défaut est activé. Tableau 3: Rapport sur la qualité de l'air Note: Dans le contexte de la déclaration du spectre, la qualité de l'air représente une interférence provenant de sources non Wi-Fi et de sources Wi-Fi non détectables par un AP Wi-Fi en fonctionnement normal (par exemple, Périphériques, périphériques 802.11 modifiés, interférence de canal se chevauchant adjacente, etc.). Les informations sur les interférences basées sur Wi-Fi sont collectées et signalées par l'AP à l'aide de la puce Wi-Fi. Un AP en mode Local recueille des informations AQ pour le ou les canaux de diffusion en cours. Un mode de moniteur AP collecte des informations pour tous les canaux configurés dans les options de numérisation. Les paramètres standard CUWN de Country, DCA et Tous les canaux sont pris en charge. Lorsqu'un rapport AQ est reçu, le contrôleur exécute le traitement requis et le stocke dans la base de données AQ. Comme indiqué précédemment, CleanAir est l'intégration de la technologie Cisco Spectrum Expert dans un AP Cisco. Bien que des similitudes puissent exister, il s'agit d'une nouvelle utilisation de la technologie et de nombreux concepts nouveaux sont présentés dans cette section. Cisco Spectrum Expert a introduit une technologie capable d'identifier positivement les sources non-Wi-Fi d'énergie radio. Cela a permis à l'opérateur de se concentrer sur les informations telles que le cycle de service et les canaux d'exploitation, et de prendre une décision éclairée sur le dispositif et son impact sur leur réseau Wi-Fi. Spectrum Expert a permis à l'opérateur de verrouiller ensuite le signal choisi dans l'application de recherche de dispositif et de localiser physiquement le dispositif en se promenant avec l'instrument. L'objectif de CleanAir est d'aller encore plus loin en éliminant essentiellement l'opérateur de l'équation et en automatisant plusieurs tâches dans la gestion du système. Parce que vous pouvez savoir ce qu'est le périphérique et ce qu'il affecte, de meilleures décisions peuvent être prises au niveau du système sur ce qu'il faut faire avec les informations. Plusieurs nouveaux algorithmes ont été développés pour ajouter de l'intelligence au travail qui a été lancé avec Cisco Spectrum Expert. Il ya toujours des cas qui nécessitent la désactivation physique d'un dispositif d'interférence, ou de prendre une décision au sujet d'un dispositif et l'impact qui implique des humains. Le système global doit guérir ce qui peut être guéri et éviter ce qui peut être évité de sorte que l'effort de récupérer le spectre affecté peut être un exercice proactif au lieu d'un réactif. Mode AP local (recommandé) (LMAP) Un AP Cisco CleanAir fonctionnant en mode LMAP dessert les clients sur la voie attribuée. Il surveille également le spectre sur ce canal et ce canal SEULEMENT. Une intégration de silicium serré avec la radio Wi-Fi permet au matériel CleanAir d'écouter entre le trafic sur le canal qui est actuellement desservi avec absolument aucune pénalité au débit des clients attachés. C'est la détection de taux de ligne sans interrompre le trafic client. Il n'y a pas de résidus CleanAir traités pendant les balayages normalisés. En fonctionnement normal, un AP de mode local CUWN exécute un balayage passif hors canal des canaux disponibles alternatifs dans 2,4 GHz et 5 GHz. Les analyses hors canal sont utilisées pour la maintenance du système telles que les métriques RRM et la détection de débrouillardise. La fréquence de ces balayages n'est pas suffisante pour collecter les dos à dos nécessaires à la classification positive des appareils, de sorte que les informations recueillies au cours de cette analyse sont supprimées par le système. Augmenter la fréquence des balayages hors canal n'est pas non plus souhaitable, car cela enlève le temps que le trafic des services radio. Qu'est-ce que tout cela signifie? Un AP CleanAir en mode LMAP scanne uniquement un canal de chaque bande en continu. Dans les densités d'entreprise normales, il devrait y avoir beaucoup d'AP sur le même canal, et au moins un sur chaque canal supposant que le RRM traite la sélection de canal. Une source d'interférence qui utilise une modulation à bande étroite (fonctionne sur ou autour d'une seule fréquence) n'est détectée que par des AP qui partagent cet espace de fréquence. Si l'interférence est un type de saut de fréquence (utilise plusieurs fréquences couvrant généralement la bande entière), il est détecté par chaque AP qui peut l'entendre fonctionner dans la bande. Figure 4: Exemple de détection LMAP AP En 2.4 GHz, les LMAP ont une densité suffisante pour assurer généralement au moins trois points de classification. Un minimum de trois points de détection est nécessaire pour la résolution de l'emplacement. Dans 5 GHz, il ya 22 canaux fonctionnant aux États-Unis, donc densité de détection et densité de localisation suffisante est moins probable. Toutefois, si des interférences sont en cours sur un canal occupé par un AP CleanAir, il le détecte et l'alerte ou prend des mesures pour atténuer si ces fonctionnalités sont activées. La plupart des brouillages observés sont limités à la partie de la bande de 5,8 GHz. C'est là que vivent les appareils grand public et donc où il est le plus susceptible d'être rencontré. Vous pouvez limiter votre plan de canaux pour forcer plus d'AP à cet espace si vous le désirez. Cependant, il n'est pas vraiment justifié. Rappelez-vous, l'interférence est seulement un problème si elle utilise le spectre dont vous avez besoin. Si votre AP n'est pas sur ce canal, il est probable que vous avez encore beaucoup de spectre à déplacer dans. Que faire si la nécessité de surveiller tous les 5 GHz est conduite par les politiques de sécurité Voir la définition AP Mode moniteur ci-dessous. Mode de moniteur AP (optionnel) (MMAP) Un AP de mode CleanAir Monitor est dédié et ne dessert pas le trafic client. Il fournit la numérisation à temps plein de tous les canaux en utilisant 40 MHz habitudes. CleanAir est pris en charge en mode moniteur avec toutes les autres applications de mode de surveillance en cours, y compris les adaptateurs wIPS et l'optimisation de l'emplacement. Dans une configuration radio double, cela garantit que tous les canaux de bandes sont régulièrement analysés. Les MMAP compatibles CleanAir peuvent être déployés dans le cadre d'un déploiement généralisé de LMAPs compatibles CleanAir pour fournir une couverture supplémentaire en 2,4 et 5 GHz, ou en tant que solution de recouvrement autonome pour la fonctionnalité CleanAir dans un déploiement AP non CleanAir existant. Dans un scénario comme mentionné ci-dessus où la sécurité est un pilote principal, il est probable que l'adaptatif wIPS serait également une exigence. Ceci est pris en charge simultanément avec CleanAir sur le même MMAP. Il existe des différences distinctes dans la façon dont certaines fonctionnalités sont prises en charge lors du déploiement en tant que solution de superposition. Ceci est couvert dans la discussion des modèles de déploiement dans ce document. Spécification du spectre Mode de connexion SE Connect (en option) Un SE Connect AP est configuré comme un capteur de spectre dédié qui permet la connexion de l'application Cisco Spectrum Expert exécutée sur un hôte local pour utiliser le CleanAir AP comme capteur de spectre à distance pour l'application locale. La connexion entre Spectrum Expert et l'AP distant contourne le contrôleur sur le plan de données. L'AP reste en contact avec le contrôleur sur le plan de commande. Ce mode permet de visualiser les données brutes du spectre telles que les tracés FFT et les mesures détaillées. Toutes les fonctionnalités du système CleanAir sont suspendues pendant que l'AP est dans ce mode et qu'aucun client n'est desservi. Ce mode est uniquement destiné au dépannage à distance. L'application Spectrum Expert est une application MS Windows qui se connecte à l'AP via une session TCP. Il peut être pris en charge dans VMWare. Dans CleanAir, le concept de qualité de l'air a été introduit. La qualité de l'air est une mesure du pourcentage de temps que le spectre à un conteneur particulier observé (radio, AP, bande, étage, bâtiment) est disponible pour le trafic Wi-Fi. AQ est une fonction de l'indice de gravité, qui est calculé pour chaque source d'interférence classifiée. L'indice de gravité évalue chaque périphérique non Wi-Fi sur les caractéristiques de l'air et calcule le pourcentage de temps pendant lequel le spectre n'est pas disponible pour Wi-Fi avec ce périphérique présent. La qualité de l'air est un produit des indices de gravité de toutes les sources d'interférence classifiées. Il s'agit alors de la qualité de l'air globale par radiochannel, bande ou domaine de propagation RF (étage, bâtiment) et représente le coût total par rapport au temps d'antenne disponible de toutes les sources non-Wi-Fi. Tout ce qui reste est théoriquement accessible au réseau Wi-Fi pour le trafic. Cela est théorique parce qu'il ya toute une science derrière la mesure de l'efficacité du trafic Wi-Fi, ce qui dépasse le cadre de ce document. Cependant, sachant que l'ingérence est ou non un impact que la science est un objectif clé si votre plan est le succès dans l'identification et l'atténuation des points de douleur. Ce qui rend une source d'interférences grave Ce qui détermine si isor n'est pas un problème Comment utiliser ces informations pour gérer mon réseau Ces questions sont abordées dans ce document. Dans les termes les plus simples, l'utilisation non-Wi-Fi se résume à la fréquence à laquelle une autre radio utilise mon spectre de réseaux (cycle de service) et à quel point elle est forte par rapport à mes radios (RSSIlocation). L'énergie dans le canal qui est vu par une interface 802.11 essayant d'accéder au canal est perçue comme un canal occupé si elle est au-dessus d'un certain seuil d'énergie. Ceci est déterminé par une évaluation claire des canaux (CCA). Wi-Fi utilise une méthode d'accès au canal d'écoute avant la conversation pour un accès PHY sans contention. Ceci est par CSMA-CA (-Acollision évitement). La RSSI du brouilleur détermine si elle peut être entendue au-dessus du seuil du CCA. Le cycle de service est le temps de fonctionnement d'un émetteur. Cela détermine la persistance d'une énergie dans le canal. Plus le cycle de service est élevé, plus souvent le canal est bloqué. La sévérité simple peut être démontrée de cette façon puis en utilisant strictement le RSSI et le cycle de service. A titre d'illustration, on suppose un dispositif à 100 cycles de service. Figure 5: Lorsque le signal d'interférence diminue - AQI augmente Dans le graphique de cette figure, vous pouvez voir que lorsque la puissance du signal de l'interférence diminue, l'AQI résultant augmente. Techniquement, dès que le signal tombe en-dessous de -65 dBm, l'AP n'est plus bloqué. Vous avez besoin de penser abut l'impact que cela a sur les clients dans la cellule. 100 cycle de service (DC) assure une perturbation constante des signaux clients avec un SNR insuffisant en présence du bruit. AQ augmente rapidement lorsque la puissance du signal est inférieure à -78 dBm. Jusqu'à présent, il y a deux des trois impacts majeurs de l'interférence définis dans la métrique de qualité de l'air basée sur la gravité: L'interférence est simple quand on regarde 100 DC. C'est le type de signal le plus souvent utilisé dans les démonstrations de l'effet de l'interférence. Il est facile à voir dans un spectrogramme, et il a un effet très dramatique sur le canal Wi-Fi. Cela se produit également dans le monde réel, par exemple dans les caméras vidéo analogiques, les détecteurs de mouvement, l'équipement de télémétrie, les signaux TDM et les téléphones sans fil plus anciens. Il ya beaucoup de signaux qui ne sont pas 100 DC. En fait, une grande partie de l'interférence qui est rencontrée est une interférence de ce type: variable à minimale. Ici, il devient un peu plus difficile à appeler la gravité. Exemples d'interférences de ce type sont Bluetooth, téléphones sans fil, haut-parleurs sans fil, dispositifs de télémétrie, les équipements plus anciens 802.11fh et ainsi de suite. Par exemple, un seul casque Bluetooth ne fait pas beaucoup de dégâts dans un environnement Wi-Fi. Cependant, trois d'entre eux avec propagation en chevauchement peuvent déconnecter un téléphone Wi-Fi si vous marchiez. En plus de CCA, il ya des dispositions dans les spécifications 802.11 telles que la fenêtre de contention, qui est nécessaire pour adapter le temps d'air de différents protocoles de base. Ensuite, vous ajoutez à ces différents mécanismes de QOS. Toutes ces réserves de médias sont utilisées par différentes applications pour maximiser l'efficacité du temps d'antenne et minimiser les collisions. Cela peut être source de confusion. Cependant, parce que toutes les interfaces sur l'air participent et se mettent d'accord sur le même groupe de normes, cela fonctionne très bien. Ce qui se passe dans ce chaos ordonné lorsque vous introduisez une énergie très spécifique qui ne comprend pas les mécanismes de contention ou même ne participe même pas au CSMA-CA, en fait, à un degré plus ou moins grand. Cela dépend du niveau d'occupation du support lorsque l'interférence est détectée. Figure 6: Différents cycles de fonctionnement des canaux Vous pouvez avoir deux signaux identiques en termes de cycle de service mesurés dans le canal et l'amplitude, mais ils ont deux niveaux d'interférence totalement différents sur un réseau Wi-Fi. Une impulsion courte répétitive rapide peut être plus dévastateur pour Wi-Fi qu'une graisse répétitive relativement lente. Regardez un brouilleur RF, qui ferme effectivement un canal Wi-Fi et enregistre très peu de cycle. Afin de faire une bonne évaluation du travail, vous avez besoin d'une meilleure compréhension de l'intervalle d'interférence minimum introduit. L'intervalle d'interférence minimum tient compte du fait que les impulsions dans le canal interrompent l'activité Wi-Fi pendant une période plus longue que leur durée réelle, en raison de trois effets: Si déjà le décompte, les périphériques Wi-Fi doivent attendre une période DIFS supplémentaire après l'interférence impulsion. Ce cas est typique pour les réseaux fortement chargés, où l'interférence commence avant que le compteur de back-off Wi-Fis ait compté jusqu'à zéro. Si un nouveau paquet arrive pour être transmis à mi-interférences, le dispositif Wi-Fi doit en outre reculer en utilisant une valeur aléatoire entre zéro et CWmin. Ce cas est typique pour les réseaux légèrement chargés, où l'interférence commence avant que le paquet Wi-Fi arrive au MAC pour la transmission. Si le périphérique Wi-Fi transmet déjà un paquet lorsque la rafale d'interférence arrive, le paquet entier doit être retransmis avec la valeur plus élevée suivante de CW, jusqu'à CWmax. Ce cas est typique si l'interférence commence en second lieu, partiellement à travers un paquet Wi-Fi existant. Si le temps de retour expire sans une retransmission réussie, alors le prochain arrêt est le double de la précédente. Cela se poursuit avec une transmission sans succès jusqu'à CWmax est atteinte ou TTL est dépassé pour la trame. Figure 7 - Pour 802.11bg CWmin 31, pour 802.11a CWmin est 15, tous les deux ont CWmax de 1023 Dans un réseau Wi-Fi réel, il est difficile d'estimer la durée moyenne de ces trois effets parce qu'ils sont des fonctions du nombre d'appareils Dans le BSS, les BSS se chevauchant, l'activité du périphérique, la longueur des paquets, les protocoles de vitesse pris en charge, la QoS et l'activité présente. Par conséquent, la meilleure chose suivante est de créer une métrique qui reste constante comme point de référence. C'est ce que la gravité fait. Il mesure l'impact d'un seul brouilleur contre un réseau théorique et maintient un rapport constant de gravité, quelle que soit l'utilisation sous-jacente du réseau. Cela nous donne un point relatif à examiner à travers les infrastructures réseau. La réponse à la question de savoir combien d'interférence non-Wi-Fi est mauvaise est subjective. Dans les réseaux légèrement chargés, il est tout à fait possible d'avoir des niveaux d'interférences non Wi-Fi qui passent inaperçus par les utilisateurs et les administrateurs. C'est ce qui conduit à des ennuis à la fin. La nature des réseaux sans fil est de devenir plus occupés au fil du temps. Le succès aboutit à une adoption plus rapide de l'organisation et à l'adoption de nouvelles applications. S'il ya des interférences dès le premier jour, il est très probable que le réseau a un problème avec cela quand il devient suffisamment occupé. Lorsque cela se produit, il est difficile pour les gens de croire que quelque chose qui a été bien apparemment tout le long est le coupable. Comment utilisons-nous les mesures de qualité de l'air et de gravité de CleanAirs AQ est utilisé pour développer et surveiller une mesure de spectre de base et alerter sur les changements indiquant un impact sur le rendement. Vous pouvez également l'utiliser pour l'évaluation des tendances à long terme par le biais de rapports. La gravité est utilisée pour évaluer le potentiel d'impact d'interférence et pour hiérarchiser les dispositifs individuels pour l'atténuation. Les émetteurs non Wi-Fi sont moins conviviaux quand il s'agit de caractéristiques uniques qui peuvent être utilisés pour les identifier. C'est essentiellement ce qui a rendu la solution Cisco Spectrum Expert si révolutionnaire. Maintenant, avec CleanAir il ya plusieurs AP qui potentiellement tous entend la même interférence en même temps. La corrélation de ces rapports pour isoler des instances uniques est un défi qui a dû être résolu pour fournir des fonctionnalités avancées, telles que l'emplacement des périphériques d'interférence, ainsi qu'un compte exact. Entrez le Pseudo MAC ou PMAC. Parce qu'un périphérique vidéo analogique n'a pas d'adresse MAC ou, dans plusieurs cas, toute autre étiquette numérique d'identification, un algorithme a dû être créé pour identifier les périphériques uniques qui sont signalés à partir de sources multiples. Un PMAC est calculé comme faisant partie de la classification des appareils et inclus dans l'enregistrement des dispositifs d'interférence (IDR). Chaque point d'accès génère l'ACGP indépendamment, et bien qu'il ne soit pas identique pour chaque rapport (au minimum, le RSSI mesuré du dispositif est probablement différent à chaque point d'accès), il est similaire. La fonction de comparaison et d'évaluation des PMAC est appelée fusion. Le PMAC n'est pas exposé sur les interfaces client. Seuls les résultats de la fusion sont disponibles sous la forme d'un ID de cluster. Cette fusion est discutée ci-dessous. Figure 8: Détection brute de l'interférence Dans ce graphique, vous pouvez voir plusieurs AP tous les rapports DECT, tels que l'énergie du téléphone. Toutefois, les points d'accès dans ce graphique sont en fait rapport sur la présence de deux distincts DECT, tels que les sources téléphoniques. Avant l'attribution d'un PMAC et la fusion ultérieure, il ya seulement la classification des appareils, qui peut être trompeur. L'ACGA nous donne un moyen d'identifier les sources de brouillage individuelles, même si elles n'ont aucune information logique pouvant être utilisée comme une adresse. Il existe plusieurs AP qui signalent tous un périphérique similaire. Pour chaque AP de rapport, l'ACGA est affectée au signal classifié. L'étape suivante consiste à combiner les PMAC qui sont probablement le même périphérique source à un seul rapport pour le système. C'est ce que fait la fusion, en consolidant plusieurs rapports à un seul événement. La fusion utilise la proximité spatiale des AP de génération de rapports. S'il y a six IDR semblables avec cinq de points d'accès au même étage et un autre d'un bâtiment à un mille de distance, il est peu probable que ce soit le même brouilleur. Une fois qu'une proximité est établie, un calcul de probabilité est exécuté pour faire correspondre les IDR distincts qui appartiennent et le résultat est assigné à un cluster. Un cluster représente l'enregistrement de ce périphérique d'interférence et capture les AP individuels qui en font rapport. 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. This is disabled by 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.