Question : GSM EFR <-> G711 transcoding on cisco 2651XM with NM-HDV=

I have to interconnect the Softswtich and the GSM BSC with VoIP. However, the GSM BSC can only talk in GSM EFR codec and the softswitch can only support G711. So transcoding is required.

Only Cisco 2600,3600 and AS5300 support GSM EFR. So we choose the Cisco 2651XM. As it is shown on my drawing below. Can we do a IP to IP transcoding for those two codecs or we have to use the E1 ports to cross-connect those two VoIP end points?

I also found that the Cisco 2600 transcoding config is a bit different from the Cisco 2800. So I really appreciate if someone can show me the configuration on this. Thank you very much!

Answer : GSM EFR <-> G711 transcoding on cisco 2651XM with NM-HDV=

controller e1 x/x
!i will make it CAS
ds0-group 0 timeslots 1-31 type r2-digital r2-compelled ani

dial-peer voice 1 pots
destination-pattern xxxxx
forward-digits all (as you want)
port x/x:x

dial-peer voice 2 pots
incoming called .
direct inwa


make it for both sides