Network Computing is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Venturing Into the Wireless Future

The AirStation g54 is based on another first--Broadcom's 11g chipset (the company never offered an 11b or 11a chipset)--so I was not surprised to encounter problems with performance, range, interoperability and management. If there's a silver lining, it's that early-release products help us find problems that need to be addressed before the technology is enterprise-ready.

The AirStation g54 is intended to support clients of the faster 802.11g standard while maintaining legacy support of 802.11b users. To be backward-compatible with 802.11b, 11g relegates administrators to the three nonoverlapping channels of 11b--five short of its 54-Mbps rival, 802.11a. This, along with the device's lack of PoE (Power Over Ethernet) capability and the fact that it isn't designed to mount on a wall or in a drop ceiling but rather to be placed on a desktop, make it difficult to deploy the AirStation g54 even in a SOHO setting.

I configured the AirStation g54 through a simple utility and then accessed the Web management pages from a PC on the same subnet. Because the device is an access point and broadband router in one, it is set up to run NAT (Network Address Translation), which shares one external IP address with multiple, privately addressed PCs, and to hand out addresses via DHCP. However, both these features can be disabled.

Buffalo AirStation q54
click to enlarge

I wanted to get a feel for how the AP handles file transfers to mixed nodes and how well it can handle the load of many clients transferring simultaneously, so I tested throughput using 11g and 11b clients alone and simultaneously. I plugged the 11g and 11b clients into a 1.2-GHz Microsoft Windows XP laptop and batch-transferred 1,000 iterations of a 1-MB, TCP-based unidirectional long-file receive to the various setups. The results were less than spectacular (see "Throughput Results," below).

The AirStation g54 offers a proprietary turbo mode for 11g clients. Unlike the turbo modes of 802.11a APs, the g54's turbo mode doesn't boost the data rate higher than 54 Mbps; it simply makes more efficient use of the available bandwidth. To do this, the g54 operates using only the packet timing of 11g clients--9 milliseconds--ditching the 20-ms timing required by 11b traffic. But when using the turbo mode, I was afforded only about one extra megabit per second in most test environments, and had to sacrifice compatibility with 802.11b. Still, you want high performance and are willing to forgo 11b compatibility, 11a is a better solution.

  • 1