Asterisk res_pjsip uses a default Timer B of 32000 ms (32 seconds), which is 64 times its 500 ms default T1.

Checked 2026-09-25

Vendor
Sangoma
Product
Asterisk res_pjsip
Subsystem
system timers
Deployment
on-premises
Region
not restricted
Release range
master branch as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-asterisk-timer-b-default. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-asterisk-timer-b-default

BibTeX

@misc{warmtransfer-claim-sip-calls-drop-30-seconds-asterisk-timer-b-default,
  title  = {Calls that drop after about 30 seconds: source note sip-calls-drop-30-seconds-asterisk-timer-b-default},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-calls-drop-30-seconds-asterisk-timer-b-default},
  note   = {Source note sip-calls-drop-30-seconds-asterisk-timer-b-default, checked 2026-09-25}
}

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