multicast storm in wireless network

I'm in the process of adding wireless capablities to our lan. I've installed the first 3com access point (11g) and it works great.

I'm experiencing the following problem:

whenever I install the second Access Point, my network slows down considerably. After some investigating, I noticed that multicasts went from an average of 50-80 to 2900+ as soon as the second AP was powered on. I see a tremendous amount of retransmissions, acks, etc. I've swapped out the AP's but I still get this problem. I need to install 8 AP's.

Has anyone come across this problem? 3Com was no help.
I have a simple nt4 network with about 200 users.

nt4 domain
1 pdc, 2 bdc
win2000 server for dhcp

Thanks

If possible could you post a small capture file with samples of the traffic so that we can analyse it. Are you sure its multicast traffic ? 802.11 does generate a lot of administrative overhead in the form of beacons etc.

Sahir,

thanks for replying. How do I go about attaching a file? Can you use a sniffer 4.5 format?

On the sniffer dashboard, the multicasts/s shoots up from 50-80 to currently 3047, all other values being about the same. This happens as soon as I plug in the second access poin, and disappears when I unplug it.

packets/s = 3044
utilization = 2
errors/s = 0
drops/s = 0
bytes/s = 228021
broadcasts = 2
multicasts/s = 3036

Thanks

Emin

Hmm if you have a little bit of space to upload the capture files to it would be a good idea.. maybe a geocities account or something.

I guess the sniffer file format should do.. see if it can save as a libpcap packet capture file since thats more universally supported. No need to give a whole lot of traffic, just a small sample is fine.