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New Member

Fax G711 to T.38 Problem

Hi everybody,

I have a problem with my Voice Gtaeway 1760 concerning fax issue!!

I think that the problem is that the Gateway is unable to change the codec from G711ulaw to T.38 !! and i don't know why!

My test is simple: i call the number via PSTN and i expect that tone change to modem but i don't hear that, and when i use the command "sh voice call status" i can see the call but the codec is G711 and i doesn't change to t.38!!

could the problem be because of DSP?

PlZ help me it's really urgent.

Thank in advance

New Member

Re: Fax G711 to T.38 Problem

Sorry, here it the dial peers i'm using :

-------Dial-peer for incoming PSTN Call---------

dial-peer voice 100 pots

incoming called-number ..


-------Dial-Peer voip pointing to the fax server------

dial-peer voice 10 voip

description -- To FAX Server

destination-pattern 6.

session target ipv4:

dtmf-relay h245-alphanumeric

codec g711ulaw


i used also these command ::

voice service voip

fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback cisco

Thx again

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