Once upon a time, we were awed by the 11-Mbps top throughput of 802.11b wireless networking and were glad to have it. Then last year, the much faster 802.11g appeared, with its 54-Mbps data rate threshold and 802.11b compatibility. But if that still isn’t enough to keep your business or home network humming, consider the new Super G alternatives now on the market from D-Link and Netgear.
Based on wireless chipsets by Atheros, Super G products claim to double the top data rate of standard 802.11g—to a whopping 108 Mbps—while still working with other 802.11b and 802.11g devices (albeit at lower speeds). Be warned, however, that Super G is not standards-based, so compatibility is up to each manufacturer and is not inherent in the specification.
Super G products employ a number of technologies to achieve performance gains over standard 802.11g products. The primary (and most problematic from a standards standpoint) is channel bonding. Super G products can bond two 20-MHz channels together. This 40-MHz footprint is centered on channel 6. This can cause adjacent channel interference on the only other two nonoverlapping channels in the 2.4-GHz spectrum, channels 1 and 11. That means the introduction of a Super G access point in close proximity to an existing 802.11g network can dramatically decrease the performance of the 802.11g network.
Another technology used by Super G is packet bursting, which lets the AP and client card send more packets on each transmission, thereby making better use of air time by reducing the number of interpacket intervals. In addition, Super G’s fast packets technology packs more data into each packet.
