The N Crowd: Wireless N Put To The Test

Methodology
Last year, the CRN Test Center examined a group of SOHO access points from a variety of vendors based on the draft version of the forthcoming 802.11n high-speed wireless standard (see CRNtech, Jan. 29, 2007). In the meantime, all of the major enterprise players have now jumped on the bandwagon, so reviewers set out to take a look at some of these higher-end offerings.

Reviewers extended invitations to Aruba Networks, Bluesocket, Cisco Systems, Meru Networks, Ruckus Wireless and Trapeze Networks. Only Meru and Ruckus voluntarily participated.

Meru and Ruckus, both of Sunnyvale, Calif., provided products and sent engineers to the CRN Test Center lab to help testers configure the WLAN access points and controllers. Reviewers also examined an 802.11n access point from San Jose, Calif.-based Cisco that was received from an alternate source. No Cisco engineer was present. See the article, Where's Cisco With Wireless N? for Cisco results.

Meru's offering included its AP320 access point and its MC3000 controller. The devices were running Meru software version 3.4.SR3-113. Meru's access point connected both of its radios—2.4 GHz and 5 GHz—but only the 2.4-GHz radio was left on for the main tests. The antennas were configured on a X-Y-Z axis.

The Ruckus setup included its ZoneFlex 7942 access point and ZoneDirector 1000 controller. The Ruckus software version was 3.02. The ZoneDirector is not necessary to configure the 7942 access point but with the help of a Ruckus engineer, reviewers used the ZoneDirector to tweak various settings to optimize performance.

The Test Center 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 ThinkPad T61 with a Linksys Wireless N WPC4400N adapter card. The ThinkPad and the TravelMate ran Microsoft Windows XP SP2 while the Toshiba ran 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 decided not to install the latest wireless client drivers because they wanted to test under real-world conditions.

Reviewers ran the tests with single access point configurations on Channel 6 and kept channelization at 20 MHz. In addition, testers asked Meru and Ruckus to provide a 2x2 MIMO antenna setup running at 2.4 GHz.

The Test Center evaluated the products on network performance, management features and functionality and channel programs, using Ixia's IxChariot testing software after finding considerably poorer results with SolarWinds' Engineer's toolset.

With IxChariot, reviewers ran downlink, uplink and uplink/downlink tests, each with four sets of TCP socket pairs of traffic. IxChariot was configured to run in batch mode for one minute. Reviewers used the same configuration file for all tests. They tested orientation at 45-degree and 90-degree angles with respect to an access point, and also tested the notebooks with WPA2-PSK security features turned on.

Next: Ruckus ZoneFlex 7942