Where's Cisco With Wireless N?

wireless LAN 802.11n (see related story).

Nevertheless, reviewers were able to obtain a Cisco Aironet 1250 Series 802.11n access point elsewhere, from a source that asked to remain anonymous. So while reviewers did put the access point through its paces in the lab, they were unable to obtain a Cisco controller to go with it. Since other units tested were attached to controllers, CRNtech decided not to list the results of the Cisco testing comparatively against its rivals.

But here's what the Test Center found. Reviewers selected three notebooks -- a Toshiba Portege M700-S7002 with an Intel chipset 4965AGN, an Acer TravelMate 6291 with an Intel chipset 3945ABG and an IBM T61 with a Linksys Wireless N WPC4400N adapter card. The IBM and Acer systems were running Microsoft Windows XP SP2 while the Toshiba was running Vista. To eliminate unforeseen network problems, reviewers disabled the LAN adapter and only turned on the IPv4 connection on the wireless adapter.

Reviewers downloaded the latest Linksys driver and added a Microsoft hotfix for the XP clients to get WPA2-PSK encryption working.

Reviewers activated the Cisco AP with 2.4-GHz antennas only and its default configuration. The 1250's software version is 12.4(10b)JA.

The Results
During the performance test, the Aironet 1250 had problems connecting with all of the client notebooks. Reviewers first ran Ixia's IxChariot, the most throughput-intensive uplink/downlink test, with all the clients and received an average score of 11.7 Mbps, a far cry from the up to 300 Mbps per radio the San Jose, Calif.-based vendor claims.

After several tries, reviewers noticed that the Linksys card kept releasing its network connection. Reviewers could not remediate the problem, so they removed the IBM-Linksys client from the test. With the Toshiba and Acer notebooks, Cisco received a more favorable result of 88.9 Mbps for uplink/downlink. Cisco also achieved favorable results with the uplink- and downlink-only tests on the two clients.

In addition, reviewers examined Cisco's Web-based management features, using the vendor's management utility to set up the access point for testing.

As an enterprise solution, configuration is detailed. The Express Setup includes the basics but also allows for more advanced setup options such as defining an SNMP community and configuring radio settings in 2.4-GHz or 5-GHz modes. Users can also define the access point's role and set the device up as a bridge, repeater or scanner.

In the Security section of the interface, a static WEP key can be created. WPA and EAP authentication can be enabled as well. Authentication can be done against a RADIUS server. The SSID is set here as is the setup of a VLAN. A useful feature in this section is a hyperlink from each setup option that opens up to a page where that option is explained in detail.

All in all, the Cisco interface is easy to navigate yet gives an administrator control over the smallest detail of the wireless network.

After being notified of the testing results, Cisco executives protested, disagreeing with the methodology and claiming that the access point did not contain Cisco's most recently updated software version.

Reviewers offered to rerun the tests with the updated software and invited Cisco to provide an engineer to participate. Cisco wouldn't provide the new software without disclosure of information that could have compromised our source for the device. CRNtech declined to do so.

So, What To Believe?
An 802.11n buildout is not a small investment for a customer, nor for a VAR that's selling that particular customer on top-flight performance. The results of CRNtech's testing did not come close to Cisco's claims of its top-level performance of 300-Mbps throughput, and it is unlikely that customers would achieve that level of performance in a real-world situation.

Both customers and partners should keep this in mind before investing in this or any other 802.11n technology.