V22 and V22bis softmodem problem

Asterisk Asterisk Support
1

Hello!
I am new with Asterisk and my project is to setup a V22 server with Asterisk using a softmodem. If I resolve this I will need for 2400 baud rate but now I only try with 1200 baud.

I installed Asterisk 18 with soft_modem module.(in fact I used a document on forum and it was used version 18)

All configured : when calling, Asterisk answer but all data seem 0x3F.

The config of extension is:

exten => s,1,Set(VOLUME(TX)=0)
exten => s,n,Set(VOLUME(RX)=0)
;exten => s,n,Set(JITTERBUFFER(adaptive)=200,60)
exten => s,n,Answer()
exten => s,n,Softmodem(127.0.0.1, 5001, ,v(V22)ld(7)s(1)e)
exten => s,n,Hangup()

And sometimes jitter function fails, too.
Is there any another configuration that I can resolve this problem?

Thanks!

2

This is an example of incoming data. Only some little parts of selected area is looks like ok but it fails again.

image
image1920×337 118 KB

3

Which codec are you using? For reliable operation of V.22 it needs to be alaw or ulaw, depending on your country.

4

Hello David,
Modem is working on alaw codec, but I didn’t filter it in pjsip configuration. Pjsip supports all in my config. Should i filter?

5

You should always limit the codecs to what is reasonable. Large numbers of codecs can cause request packets to become too large for some systems.

6

Hello,

I added the part of endpoint in pjsip.conf file;
disallow= all;
allow=alaw;

but get same result.
Is there any another configuration I can try? Could not add jitter configuration above because it fails.

7

Are you sure the complete path to the PSTN is G.711?

8

Yes, in the product document it is with G711 - alaw codec.
I got a port from Huawei SoftX3000 and get this result, to share some more specific information.

Below is my extensions.conf:
exten => s,1,Set(VOLUME(TX)=0)
exten => s,n,Set(VOLUME(RX)=0)
exten => s,n,Answer()
exten => s,n,Softmodem(127.0.0.1, 5001, ,v(V22)ld(7)s(1)e)
exten => s,n,Hangup()

Below is my pjsip.conf endpoint part:
type=endpoint
context=test
disallow=all
allow=alaw
outbound_auth=mytrunk
aors=mytrunk

And, it would be better if I could get some debug information if I could, because I can only see the result now and can not see the reason why.

9

Hello, is there any another suggestions?