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Hello,

I am looking for some information regarding co-located 802.11b and 802.11g systems. I have read that the typical maximum data rate for co-located systems is 36Mbps but I'm trying to find out some 'real world' examples of data rates when there is 1 user per AP, 2 users per AP, 3 users per AP, etc. Is it just a case of dividing 36 by 1, 36 by 2, 36 by 3, etc?. Is it really that simple? But what about the additional CTS-to-Self traffic and other protection mechanisms?

Also, it would be good to have the data rate values for each additional user association with 802.11g only - for comparison.

I would be extremely grateful if anyone out there can help

Many thanks

Keep in mind that not every associated station will be using the maximum data rate. Due to distance from the AP and other environmental factors stations use automatic rate selection and lower their rate in order to stay connected. You could have an 802.11b station using 2mbps and an 802.11g station using 6mbps due to distance from the AP in addition to an 802.11g station that is using HR-DSSS due to distance from the AP and ARS, as well as the overhead of the protection mechanism. There is not a written in stone formula that states if given x number of b stations and y number of g stations you will have z max data rate. There are too many things involved. Try setting up an 802.11g AP and connecting with an 802.11g station passing traffic. Create a baseline and associate with an 802.11b station and start passing traffic. Then create another baseline to compare. Also move the stations away from the AP to see the drop in data rate due to ARS and baseline again.