Asterisk NCS patch

Disclaimer: I’m not a programmer! If you decide to use this, use it at your own risk!

For a couple of days I’ve been trying to find a working patch for Asterisk PBX, that would allow me to use an eMTA device (which is essentially a cable modem with voice terminal adapter), provisioned according to [some of] the PacketCable specifications – i.e. with MGCP/NCS. So, I’ve found a patch on the Net, written by Jason Burton in 2006.

Disclaimer: I’m not a programmer! If you decide to use this, use it at your own risk!

When I tried to apply it on a vanilla 1.4.18 Asterisk source tree, it spew a lot of rejects, which then I kind of fixed. So, here you can find the patch itself.

Apply it like this:

cd /usr/src/asterisk-1.4.18/channels/
patch –dry-run -p1 < [full path to/]ncs-packetcable-minus273.patch

Look carefully if there are any rejects. If not:

patch -p1 < [full path to/]ncs-packetcable-minus273.patch

Then, of course, you have to recompile and configure asterisk to accept eMTA devices.

Disclaimer: I’m not a programmer! If you decide to use this, use it at your own risk!

Please, note, that I’m not responsible for any problems, that could arise after applying this patch!

Edit: You have to enter ncs=1 in every endpoint’s configuration in your mgcp.conf. E.g.:

[192.168.200.2]
host=192.168.200.2
dtmfmode=rfc2833
ncs=1
nat=no
slowsequence=yes
canreinvite=yes
wcardep=aaln/*
context = eMTAs
immediate=no
line => aaln/1
context = eMTAs
immediate=no
line => aaln/2

Just a quick note – there is a new version of the patch for 1.4.24.1 version of Asterisk, that applies without too much warnings. Have no idea if it works, though. Test it and see.  http://www.minus273.org/wp-content/uploads/2008/03/ncs-packetcable-minus273-1424.patch