When sending a REGISTER request to Asterisk with a specified "expires" value in the "Contact" header, Asterisk generates its 200 response with "expires" value reduced by 1 second. e.g. In the example below, the client uses 180 seconds, and Asterisk responds with 179 seconds.
This leads the client that generated the REGISTER to then re-register 1 second sooner then it would otherwise. The cycle repeats, over and over, with the expiration dropping by 1 second upon each and every re-registrtion, until the minimum allowable registration interval is hit (60 seconds). When the client re-registers on 59 seconds, Asterisk then rejects the registration, on account of the expiration value being too low.
Example REGISTER request:
Example 200 response:
Relevant log output
No response
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Severity
Minor
Versions
18.20.1
Components/Modules
res_pjsip
Operating Environment
Ubuntu 20.04.6 LTS, x86_64, 5.4.0-105-generic
Frequency of Occurrence
Constant
Issue Description
When sending a REGISTER request to Asterisk with a specified "expires" value in the "Contact" header, Asterisk generates its 200 response with "expires" value reduced by 1 second. e.g. In the example below, the client uses 180 seconds, and Asterisk responds with 179 seconds.
This leads the client that generated the REGISTER to then re-register 1 second sooner then it would otherwise. The cycle repeats, over and over, with the expiration dropping by 1 second upon each and every re-registrtion, until the minimum allowable registration interval is hit (60 seconds). When the client re-registers on 59 seconds, Asterisk then rejects the registration, on account of the expiration value being too low.
Example REGISTER request:
Example 200 response:
Relevant log output
No response
Asterisk Issue Guidelines