Re: estimating VoIP data traffic size from VoIP signaling traffic size ?

[Bill Woodcock <woody () pch net>]

    > is there any statistics on aggregated VoIP signaling
    > bandwidth and aggregated VoIP data bandwidth? eg. if
    > we monitored there is 2Mbps(average) traffic on VoIP
    > signaling protocol ports ( including SIP, H.323,
    > MGCP), how could we estimate average VoIP data
    > bandwidth? 

For any given user population, you could calculate the ratio, but that's 
an observation, not a predictive rule.  And it would be different for 
every population.

On the other hand, if you have access to the signaling traffic, it 
_contains_ the statistics about the data traffic.  Byte-counts, times, 
loss, latency, jitter, and out-of-order delivery.  All right there in each 
SIP-Bye message.  Which, of course, you aren't guaranteed to see, but 
there again, you can extrapolate from knowing what portion you are seeing.

                                -Bill