I would like configure my firewall to allow IP Telephony services over the VPN. Kindly advice on what i need to do.
u didnt say if remote access vpn or site site?
any way the moste important thing is to know that the firewall in general not very good in QoS like a router
but u can put the voice traffic based on its prevously marked dscp or ip precedance
put them in priority queue
and also u have to enable h323 inspection
alsp mgcp and
for all those call signaling u need to enable the option rtp-conformance under the h323,sccp parameters in the global_policy inspection
and dont forget to match the interesting traffic with the voice protocols like sccp and h323 for priority and vpn tunnel estblishmnet
i have given u a background now just follow the folowing link as it is simple and detaild regarding ur case
QoS for VoIP Traffic on VPN Tunnels :
PIX/ASA 7.x: Enable VoIP :
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