04-21-2008 04:59 AM - edited 03-15-2019 10:11 AM
Hello,
We are trying to interconnect a CUCM 6.1 with an IP-to-IP GW in order to translate H323 messages to SIP (Sip Provider).
The problem is that we are not able to place calls with G729(MTP) but only G711.
We need Fast Start with G729 MTP because our Sip Provider supports "Early Offer"
Is there any specific config that has to be done on IP-to-IP GW in order to enable
fast start ?
Thanks
Christos
04-21-2008 06:23 AM
The default is fast start on the gateways but this is the command to enable/disable it:
voice service voip
h323 call start (fast|slow)
You may find this guide to be helpful as well covers H323 - SIP.
http://www.cisco.com/en/US/docs/ios/12_3/multiservice_ip2ip/guide/gw_ch2.html
Matt
04-21-2008 06:28 AM
Thanks Matt,
I have already done that but I am stil not able to place calls with G729 MTP
Chris
04-21-2008 06:33 AM
Can you upload your config? Have you read the documentation i added?
Matt
04-21-2008 06:53 AM
Please find below my config:
voice service voip
address-hiding
allow-connections h323 to h323
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
h323
emptycapability
h225 h245-address on-connect
h245 passthru tcsnonstd-passthru
sip
rel1xx disable
voice class codec 30
codec preference 1 g729r8
codec preference 2 g729br8
codec preference 3 g711alaw
codec preference 4 g711ulaw
voice class h323 1111
h225 connect-passthru
call start fast
h245 passthru all
telephony-service ccm-compatible
ccm-compatible
dial-peer voice XXX voip
voice-class codec 30
voice-class h323 1111
incoming called-number .
no vad
dial-peer voice XXX voip
preference 2
destination-pattern .T
redirect ip2ip
voice-class codec 30
session protocol sipv2
session target ipv4:X.X.X.X
no vad
Thanks
Chris
04-21-2008 07:12 AM
Hi Chris
It seems a lot of people have had similar problems. Take a look at this one:
Looking at the other guide it says that the codec and payload need to be assigned statically. Could give this a try:
dial-peer voice 40 voip
codec G729r8 bytes 30
Also do you have any transcoding setup? As this will be required to go from g711 to g729.
HTH
Matt
04-21-2008 10:35 AM
Hello Matt,
Thanks for your reply.
According to some documents that I have already read, there is no need for transcoding. Besides it is mandatory for us to
have G729 for the entire voice path.
Another fact that makes me believe that the above scenario is true, is that on CUCM's H323
Trunk Configuration page I have ortion for G729 fast start.
I hope i am not far away from the truth !!
Chris
04-21-2008 11:18 AM
If the call starts with G729 then i guess you wouldnt need a trascoder but you would need the MTP for the h323 to sip part.
Maybe have a look at the call manager SDI logs it may shed some light as to what is happening. To me it seems like a resources issue if g711 works but g729 doesnt. I could be very wrong though.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide