H323 fax

[chuankokping]

Hi,

I do have a H323 gateway, the voice call are working perfectly. but the fax via the VG224 cannot go thru. but if i forward it to the MGCP gateway, the fax can go thru. my dial peer is as below:

dial-peer voice 108 pots
destination-pattern [1-9].......
incoming called-number 8...
no digit-strip
direct-inward-dial
port 0/0/1:15

Can someone advise on it?

Thanks

[loucanick]

What does the incoming voip dial peer look like??

[chuankokping]

dial-peer voice 1 voip

destination-pattern 8...

session target ipv4:10.1.254.37

[loucanick · Accepted solution]

I would add codec and statements for fax passthrough (modem passthrough) . You want g711 for passthrough. If doing fax relay (t.38) then you would need appropriate config statements on the voip dial peer.

Something like this:

dial-peer voice 100 voip

incoming called-number .

modem passthrough nse codec g711ulaw

etc....

The incoming voip dial peer needs to be configured properly to allow the fax transmission to come into the gateway clearly. Then the dialed number gets the call routed to the appropriate voice port.

Good reference:

http://www.cisco.com/en/US/partner/docs/ios/voice/fax/configuration/guide/12_4/vf_12_4_book.html

[chuankokping]

let me try out.