The typical peak throughput (sustained data rate) of an 802.11b wireless connection under ideal conditions for end user data is actually 4-5 Mbps. This level of performance assumes a wireless client in very close promixity (within a few meters) of the base station or other communication endpoint. Due to the distance-sensitive nature of Wi-Fi signaling, 802.11b throughput numbers will decrease the client moves further away from the base station.
The theoretical peak bandwidth of an 802.11b wireless connection is 11 Mbps. This is the performance number advertised on 802.11b Wi-Fi equipment, that many people equate with the expected "Speed" of a network. However, this level of performance is never realized in practice due to network overhead and other factors. What then is the actual network speed of 802.11b?
Some proprietary Wi-Fi products based offer "22 Mbps" bandwidth by extending the standard 802.11b signaling technology. Unfortunately, the actual throughput of these networks is not double that of ordinary 802.11b network, although typical peak throughput may increase up to a 6-7 Mbps level.
The large difference between theoretical and actual data rates for 802.11b is due primarily to protocol overhead. Wi-Fi generates a relatively large amount of traffic to maintain connections, coordinate the sending and acknowledgement of messages, and maintain other private state information. Throughput also decreases when interference in the 802.11b signal range (2.4 Ghz) is present. Interference often causes re-transmissions due to data corruption or packet loss.
While peak data rates may be acheivable at times, many 802.11b home network links typically run at 2-3 Mbps. This is still faster than broadband Internet connections, that normally operate at 0.5-2 Mbps peak for downloads. Because the Internet connection is often a bottleneck, 802.11b LAN throughput is effectively reduced to that of the broadband access.
Finally, the perceived "Speed" of a network is determined not only by available bandwidth but also by network latency (see sidebar).
Some proprietary Wi-Fi products based offer "22 Mbps" bandwidth by extending the standard 802.11b signaling technology. Unfortunately, the actual throughput of these networks is not double that of ordinary 802.11b network, although typical peak throughput may increase up to a 6-7 Mbps level.
The large difference between theoretical and actual data rates for 802.11b is due primarily to protocol overhead. Wi-Fi generates a relatively large amount of traffic to maintain connections, coordinate the sending and acknowledgement of messages, and maintain other private state information. Throughput also decreases when interference in the 802.11b signal range (2.4 Ghz) is present. Interference often causes re-transmissions due to data corruption or packet loss.
While peak data rates may be acheivable at times, many 802.11b home network links typically run at 2-3 Mbps. This is still faster than broadband Internet connections, that normally operate at 0.5-2 Mbps peak for downloads. Because the Internet connection is often a bottleneck, 802.11b LAN throughput is effectively reduced to that of the broadband access.
Finally, the perceived "Speed" of a network is determined not only by available bandwidth but also by network latency (see sidebar).
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