How to connect to Huawei devices

Huawei develops various devices which has nasty bugs in SIP implementation.

Huawei sends pagtches to Asterisk to cripple Asterisk to support their non-standard SIP implementation but do not fix their own implementations.

One we encountered is then in SIP INVITE message Asterisk sends line:

a=silenceSupp:off - - - - -

Huawei softswitch does not like it and returns error.

Related links:

• http://lists.digium.com/pipermail/asterisk-dev/2006-March/019067.html
• http://lists.digium.com/pipermail/asterisk-dev/2006-March/019156.html
• http://bugs.digium.com/view.php?id=6669

Provider which uses Huawei insisted we should patch (criple) Asterisk to make to work with their softdwitch. Instead we put middle server between our Asterisk server and their softswitch:

Our main Asterisk <---> Patched Asterisk <---> Huawei softswitch