Asterisk JITTERBUFFER function details

Asterisk Asterisk SIP
1

Asterisk v15 documentation states that JITTERBUFFER function is used to “add a Jitterbuffer to the Read side of the channel”. Take this dialplan example:

[from-pstn]
exten => 1234,1,Set(JITTERBUFFER(adaptive)=default)
exten => 1234,n,Dial(PJSIP/1234)

It is safe to assume that jitter buffer is applied to the calling channel. What about the answering channel (PJSIP/1234 in this case)? Is jitter buffer applied to it as well? If not, how to apply it?

2

Yes that jitter buffer is only being applied to the inbound side. If you want to apply a jitter buffer to the outbound side you’ll need to use a pre-dial subroutine:

exten => outbound_jitterbuf,1,NoOp()
same => n,Set(JITTERBUFFER(adaptive)=default)
same => n,Return()

exten => alice,1,Noop()
same => n,Dial(${TECH}/${EXTEN},20,b(default^outbound_jitterbuf^1))

More information and examples about pre-dial handlers can be found at the following:

Application dial
Pre-Dial Handlers

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