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One of Cisco's key goals with the 1200 series is to enhance investment protection, accomplished by over-engineering the system platform and modularizing the radio platform. The result is a workhorse 802.11b WiFi access point expandable to support new radio technologies (802.11a today and 802.11g tomorrow) with enough horsepower to support migration to Cisco's IOS operating system in the future. And provided Cisco gets the IOS implementation right, you'll see enhanced security, VLANs, QoS (Quality of Service) and better roaming.

11a Support

We tested the 1200 series AP with the new 802.11a radio module in our Syracuse University Real-World Labs®. Cisco has developed an 802.11a radio module that includes a unique integrated antenna supporting both traditional omnidirectional and directional patch antenna configurations. In our testing, patch mode extended the range of 802.11a coverage in one direction by about 20 percent. Given 802.11a's range limitation, that's a pretty significant benefit. Unfortunately, there's no way to prevent someone from reorienting the antenna, a potential problem in hostile user environments.

Cisco developed its 802.11a module in-house, after its acquisition of chip developer Radiata. That makes this product the first non-Atheros 802.11a offering to hit the market. Given the inherent overhead of the 802.11 protocols, we usually expect TCP throughput numbers that are about 50 percent of the data rate. We were able to coax about 24 Mbps of 11a TCP throughput out of the Cisco box. That's not quite 50 percent, but it's comparable with first-generation products built around the Atheros chipset. We also verified that Cisco hasn't sacrificed its industry-leading 802.11b performance, which came in at nearly 6 Mbps.

To test the product in dual-mode operation, we ran performance tests with two 11b clients and two 11a clients operating simultaneously. Total average aggregate performance was nearly 28 Mbps, suggesting that your legacy 11b clients won't take a big performance hit when 11a clients are hammering the network.

The Whole Package

From a functionality standpoint, the 1200 builds on the strong feature set of past products. If you're already comfortable with the 350 series, you'll feel right at home with the 1200. Put another way, if you've ever found yourself lost in the confusing Aironet Web-based management interface on previous products, you'll likely have the same experience with this one, except you now have additional options to manage the 11a radio subsystem. In fairness to Cisco, the company has done a better job integrating 11a and 11b management than we've seen in other products, and Cisco's support for telnet command-line interface and full SNMP management (including compatibility with CiscoWorks) provides a comprehensive enterprise management implementation. Additionally once the platform moves to IOS, your router jockeys will find themselves more comfortable with wireless infrastructure.

Has Cisco made any breakthroughs in security, the number one concern of enterprises considering large-scale WLAN deployment? The short answer is no, but you can't really hold that against Cisco. Standard wireless security features are supported, including WEP and 802.1X authentication. A pre-standard version of TKIP (temporal key integrity protocol), the short-term replacement for WEP, is also supported. The product's modular radio architecture will make it relatively easy for Cisco to provide field upgrades to hardware-based AES encryption when it becomes standardized.

Aironet APs have always had a reputation for reliability: They are the types of products you could mount in the ceiling and forget about for years. Network managers at several organizations that have deployed 1200s tell me they have no complaints about the products' reliability. It will take time for Cisco to establish a track record with 11a; after all, this is its first-generation chipset and second-generation Atheros products are already on the market. And with the imminent release of 11a chips from other large semiconductor firms, such as Broadcom Corp., Intel and Intersil Corp., we question whether Cisco might be better off concentrating on infrastructure platforms rather than on radio chipsets. But the good news is the 1200's modular hardware architecture and future IOS code base don't necessarily lock Cisco in to its own chips in the long run.

As with all dual-mode products, you shouldn't fool yourself into believing that supporting concurrent 11a and 11b is as easy as installing two radios in an AP. The propagation characteristics of the two are so different that a simple overlay design will work only for limited-diameter hot-spot installations. That may improve in the long term, but today it makes system design significantly more complex. Measured by the criteria of increased functionality and flexibility at a reasonable price, however, Cisco's Aironet 1200 AP is a solid offering.

Dave Molta is a senior technology editor of Network Computing. Write to him at dmolta@nwc.com.