The following are the results of several bandwidth tests run by PassMark to illustrate the differences between 802.11b and 802.11g networks. Most notably it highlights the difference in transmission speeds when communicating between 2 wireless devices on the same network in comparison to a wireless device and a machine physically connected to the network using UTP.
The two wireless access points used were a Linksys WRT54g for the 802.11g tests and a Sprint SEP3040 for the 802.11b tests, they can both be seen in the two WirelessMon screen shots below.
802.11b access point displayed in WirelessMon
802.11g Access point displayed in WirelessMon
All test were performed using the advanced network test in Performance Test 6.0. One computer works as the server and waits for a connection from the client, the computer running as the client will connect to the server and then transmits data to the server for the duration of the test. For these test the duration was set to 180 seconds using TCP for the protocol, each test was repeated using the fixed block size of 16kb and a variable block size ranging between 20 bytes at the start of the test and gradually moving up in size to 100 bytes by the end of the test. Each test was also repeated with a signal strength of ~100% and a signal strength of ~50%.
Throughput was very low when communicating solely over the wireless connection, only reaching approximately 13% of the theoretical maximum, signal strength had a minimal impact on the speed.
Again, communication using 2 wireless devices decreased the throughput dramatically to 11% of the theoretical maximum. However there is a noticeable difference in the transmission speeds with a stronger signal, showing a 40-50% increase with a 100% signal strength. when compared to 50% signal strength.