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New Member

g729r8 bytes 40


I have two Cisco 3640 gateways with NM-HDV-2E1.

I want to change the packet size for the g729r8. But the only place to change it is in voice class codec 1.

After I change it then I should be able to link it to the dial-peer, right?

But the dial peer is configured for dial-peer voice 1 pots and there's no option for dial-peer voice 1 voice, where I would be able to link the voice class.

In my case where the dial-peer is pots

the voice-class only links to voice-class aaa and that's all.

Can anyone tell me how to change that packet size on the g729r8 codec to 40 bytes?

The ios on the first Cisco 3640 is c3640-js-mz.123-19.bin and on the second Cisco 3640 is c3640-js-mz.124-13.bin .


Re: g729r8 bytes 40

Only available in VOIP, in pots you are just handling digital|analog ports.

MAIN#conf t

Enter configuration commands, one per line. End with CNTL/Z.

MAIN(config)#dial-peer voice 1 voip

MAIN(config-dial-peer)#codec g729r8 bytes ?

Each codec sample produces 10 bytes of voice payload.

Valid sizes are:

10, 20, 30, 40, 50, 60, 70, 80, 90, 100,

110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210,

220, 230, 240.

Any other value within the range will be rounded down

to nearest valid size.

<10-244> Choose a voice payload size from the list above

Is that what you are looking for?

New Member

Re: g729r8 bytes 40

Well the thing is that the gateway is working and the dial-peer voice 1 is set to pots. I can't change it.

I created the dial-peer voice 2 voip and set the codec type, and also added the incoming called-number . which would accept all calls.

But it doesn't seem to work. Looking at the statistics it shows that dial-peer voice 2 voip is up and accepts calls but I can't see any successful calls. It only shows accepted or failed calls.

Please advice what can I do?

Thanks in advance.

New Member

Re: g729r8 bytes 40

P.S. I only accept calls from a provider. I don't forward any calls to another VOIP device.

The main problem that I have is that the provider who sends the calls, the packet size is 40 bytes, and I answer with 10 byte packets and my upstream traffic becomes much more than downstream. So to solve this issue I also need to set the g729r8 byte size to 40, but I can't understand how and where if I only accept calls to dial-peer voice 1 pots.

Please advise.

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