Cisco Cisco Aironet 3700i Access Point 백서

 

 

© 2015 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public Information. 

Page 10 of 23 

Table 1 summarizes the results of Figure 1. Forty-one measurements were made in a cubicle environment typical 

of an enterprise. Note that the Cisco access point achieved 256-QAM for 100 percent of the measurements in the 

given environment, whereas the competitive access point achieved only 51 percent (and achieved 1300 Mbps only 

7 percent of the time). 

Summary of Results of Comparison Between Competitive Access Point and Cisco Aironet 3702i 

m9 

1300 

7% 

85% 

m8 

1170 

44% 

100% 

Also note the relative consistency and uniformity of the coverage for the Cisco access point, compared to the 

spotty, inconsistent coverage of the competitive access point. This illustrates a marked difference between Cisco 

HDX and competitive solutions. 

In conclusion, a 3x3:3 architecture (with 256-QAM) offers a peak rate of 1300 Mbps, but nothing more. To achieve 

that peak rate over a useful range, products supporting Cisco HDX (such as the Cisco Aironet 2700 and 3700 

Series) provide a higher level of engineering and custom silicon that is very difficult for other equipment vendors to 

match. On the uplink, four receive antennas and an optimized MIMO equalizer extend the range of 1300 Mbps out 

to 25 feet. Even at longer ranges, the additional diversity provides a significant advantage over a 3x3:3 design.  

On the downlink, the barrier to success is even higher. An additional transmit chain is necessary, but in addition 

client-agnostic beamforming is essential to deliver the higher rates over the important ranges. For these reasons, 
ClientLink 3.0 is a key component in Cisco’s HDX solution suite. 

Features of the Cisco High Density Experience with Optimized Roaming Technology 

If you are a long-time user of Wi-Fi, at some point you have either observed someone encounter (or have 
personally suffered from) so called “sticky client syndrome.” In this circumstance, a client device tenaciously, 

doggedly, persistently, and stubbornly stays connected to an access point that it connected to earlier, even though 

the client has physically moved closer to another access point. 

Surprisingly, the reason for this is not entirely…errr…unreasonable. After all, if you are at home, you don’t want to 
accidentally connect to your neighbor’s access point just because the Wi-Fi device you’re using happens to be 
closer to your neighbor’s access point than your own. 

However, this behavior is completely unacceptable in an enterprise or public Wi-Fi environment where multiple 

access points are used in support of a wireless LAN and where portability, nomadicity, and mobility are the norm. 

In this case, the client should typically be regularly attempting to seek the best possible Wi-Fi connection. 

Some may argue that regularly scanning for a better Wi-Fi connection unnecessarily consumes battery life for the 

client device and will interrupt ongoing connectivity, making the cure worse than the disease. But this is true only if 

the client is very aggressively scanning. 

The fundamental issue with stickiness is that many client devices simply wait too long to initiate scanning for a 

better connection. These devices simply insist on maintaining an existing Wi-Fi connection even though that 

connection may be virtually unusable for anything but the most basic functionality. 

This problem also applies to and affects devices that are capable of a cellular connection. In other words, if a 

device can achieve a better connection over cellular than over an existing Wi-Fi connection, it should switch from 

Wi-Fi to cellular when Wi-Fi degrades to near unusability. 

So what is the solution? Enter Cisco’s Optimized Roaming.