Cisco Cisco Aironet 3500e Access Point 백서
Copyright 2010 CWNP Inc.
Page 3
interference, then the tradeoff of slightly higher cost is moot. Integrated spectrum analysis without a
big price premium...very nice!
big price premium...very nice!
Cisco’s employees are usually well educated, so I think the value of embedded spectrum analysis will be
made evident fairly quickly. Let me help demonstrate their value claim with a quick question. What do
WMM, airtime fairness, band steering, RRM, and inter-AP roaming have in common? Answer: they are
all L2 functions that are designed to optimize multi-service WLANs. If you rely on your wireless network
for mission-critical client access, these features are important, right? So, just as a house requires a solid
foundation, all L2 WLAN features—as well as all functions at layers 3-7—must be built on a solid RF
foundation at L1. Instability in the RF foundation leads to instability in higher layer functions. In other
words, if you want your network to support robust applications reliably, layer 1 must be reliable. MIMO
helped us out a lot here, but the RF medium is still inherently unpredictable, and it always will be. If you
can’t predict or control it, the next best thing is to monitor it, to know what is going on at the RF level,
and to respond accordingly. RF visibility is what CleanAir offers, and IMHO this is very, very good.
made evident fairly quickly. Let me help demonstrate their value claim with a quick question. What do
WMM, airtime fairness, band steering, RRM, and inter-AP roaming have in common? Answer: they are
all L2 functions that are designed to optimize multi-service WLANs. If you rely on your wireless network
for mission-critical client access, these features are important, right? So, just as a house requires a solid
foundation, all L2 WLAN features—as well as all functions at layers 3-7—must be built on a solid RF
foundation at L1. Instability in the RF foundation leads to instability in higher layer functions. In other
words, if you want your network to support robust applications reliably, layer 1 must be reliable. MIMO
helped us out a lot here, but the RF medium is still inherently unpredictable, and it always will be. If you
can’t predict or control it, the next best thing is to monitor it, to know what is going on at the RF level,
and to respond accordingly. RF visibility is what CleanAir offers, and IMHO this is very, very good.
Analysts have predicted that end-user network access will move increasingly towards wireless, and I
agree wholeheartedly. This continuing shift demands that we improve our use and understanding of the
RF medium. Embedded spectrum analysis is a great place to start. CleanAir provides us with L1
monitoring, but it doesn’t stop at monitoring. If you remember the basic history of wireless intrusion
detection, you might recall that everything started as a WIDS—wireless intrusion detection
agree wholeheartedly. This continuing shift demands that we improve our use and understanding of the
RF medium. Embedded spectrum analysis is a great place to start. CleanAir provides us with L1
monitoring, but it doesn’t stop at monitoring. If you remember the basic history of wireless intrusion
detection, you might recall that everything started as a WIDS—wireless intrusion detection
So, if you’re already familiar with the Cisco Unified Wireless Network (who isn’t these days?), you know
that Cisco APs support different “modes.” These include Local, Monitor, H-REAP, etc., and allow your AP
to support specific functions based on the use case. With the introduction of CleanAir, a new mode,
called SE-Connect, has been added.
that Cisco APs support different “modes.” These include Local, Monitor, H-REAP, etc., and allow your AP
to support specific functions based on the use case. With the introduction of CleanAir, a new mode,
called SE-Connect, has been added.
—which
offers monitoring and reporting, but not preventative response. As WIDS matured, engineers took
advantage of the 802.11 protocol, and the WIDS evolved into a responsive solution, a WIPS (wireless
intrusion prevention). Now WIPS provide monitoring and reporting, as well as automated response
(prevention). Reaction is huge. Cisco learned from WIDS/WIPS history and bypassed the lesson at the
RF level, taking us straight to RF monitoring, reporting, and automated response.
advantage of the 802.11 protocol, and the WIDS evolved into a responsive solution, a WIPS (wireless
intrusion prevention). Now WIPS provide monitoring and reporting, as well as automated response
(prevention). Reaction is huge. Cisco learned from WIDS/WIPS history and bypassed the lesson at the
RF level, taking us straight to RF monitoring, reporting, and automated response.
When you configure an AP for SE-Connect mode, the AP reboots and becomes a remote spectrum
analysis sensor for use with Cisco Spectrum Expert software (remember the 4.x update). This
analysis sensor for use with Cisco Spectrum Expert software (remember the 4.x update). This