Please call me for SIP testing on 446714@fwd.pulver.com

"Black Adder" wrote in news:4151373b$0$658$ snipped-for-privacy@uq-127creek-reader-01.brisbane.pipenetworks. com.au:

Well, some customers of us tested it as well, but when there was more than

Yeah, I was told that VOIP wouldn't work with wireless networks because it was simplex.

Proved those fools wrong. You wouldn't know the difference, it only uses

VOIP uses UDP, and does not care what the carrier is. As you suggested voice is ~ 8Kb/sec, but wireless is at least 1000 times faster (11Mb/sec for 802.11b, 54Mb/sec for 802.11g)

A lot of voip discussion happens at

gtoomey

Whoever told you that was wrong.

we have between 10 and 15 wireless workstations on one particular site. They make calls to other branches that also have wireless.

Obviously VoIP works over wireless, I do it all the time, but I would really like for people to stop saying that G729 is 8Kbps over a wireless IP connection (or any other IP connection).

The 8Kbps specified in G.729 is the compressed audio stream. It does not include the IP, 802.3, 802.11a/b/g, PPP, ATM, or whatever overhead. The actual bandwidth used will also vary depending on the sample rate.

So, a G.729 VoIP call with a 20ms sample rate (not the only one but the most common) running over 802.3 Full Duplex Ethernet (its a little less on half-duplex) will use about 40Kbps. Now this is an approximation, I assume an IP packet header or 40B (Bytes not bits).

I'm not sure what the overhead is on 802.11a/b/g but I doubt it's much, if any, more then 802.3. If anyone knows, please post it.

The big issue on wireless is QoS, even the best AP that are designed for VoIP can't do much more then 8 calls.

RC

Gregory Toomey said

And nowhere near that in reality. Especially with any decent form of security.

Try 20-25Mbps if you are sitting right on top of the AP and closer to 10-