If you download Asterisk 17 and start it up, you might be one of the people that notices the following messages:

chan_sip.c:35350 deprecation_notice: chan_sip has no official maintainer and is deprecated. Migration to
chan_sip.c:35351 deprecation_notice: chan_pjsip is recommended. See guides at the Asterisk Wiki:
chan_sip.c:35352 deprecation_notice: https://wiki.asterisk.org/wiki/display/AST/Configuring+res_pjsip
chan_sip.c:35353 deprecation_notice: https://wiki.asterisk.org/wiki/display/AST/Migrating+from+chan_sip+to+res_pjsip

If you are using chan_pjsip, which has been available in Asterisk since version 12 was released in 2013, you’ll never see this message. But, if you do see this message, do not be afraid! chan_sip is not being removed yet. These messages are there to signal to you that chan_sip is officially transitioning from “extended” to the “deprecated” support status. For the last 5 years, chan_sip has already been in the “extended” support state, which means that any and all support (and patches) is provided only by the community, not by Sangoma (or previously Digium). During these 5 years, although a handful of changes have been merged into chan_sip, they have oftentimes caused regressions and exposed additional problems for users. This is not a healthy situation and is due to inherent architectural problems  and limitations of chan_sip.

In contrast, chan_pjsip, which is in the “core” support status and does receive direct attention from Sangoma, has continued to see further adoption. Greater adoption leads to improved interoperability, a decrease in the number of open bugs, and the addition of new, exciting features that surpass the capabilities of chan_sip, and provide greater usability. Some of these include:

PJSIP Wizards
SRV/NAPTR DNS Support
“line” Support

It has reached the point where chan_pjsip sufficiently serves the vast majority of users, and that the time is right to transition chan_sip to the “deprecated” support status, in favor of chan_pjsip. As of Asterisk 17’s release, there will be at least a 4-year time frame before the potential removal of chan_sip from Asterisk may happen. At that time, it will be up for debate and discussion. If you’re not already using chan_pjsip, now is a great time to begin trying, testing, and deploying chan_pjsip. If you need help with migrating, check out the following resources:

https://wiki.asterisk.org/wiki/display/AST/Configuring+res_pjsip
https://wiki.asterisk.org/wiki/display/AST/Migrating+from+chan_sip+to+res_pjsip
https://wiki.asterisk.org/wiki/display/AST/res_pjsip+Configuration+Examples
https://wiki.asterisk.org/wiki/display/AST/PJSIP+Configuration+Wizard
https://wiki.asterisk.org/wiki/display/AST/Configuring+res_pjsip+to+work+through+NAT

If you encounter problems, don’t hesitate to use the Community Forums. If you encounter a bug, file an issue on the Issue Tracker.

And, if you’ve got the urge to do something immediately, give the new Asterisk 17.0.0-rc2 release, which was made available today, a try! It includes the latest security fixes and a fix for message waiting indicator functionality that we felt was important to make available in the first 17.0.0 release.

If you’d like to hear more about Asterisk 17 join us at AstriCon in Atlanta, Georgia! If you’re already planning to go don’t hesitate on booking your room, the AstriCon hotel room block cut-off date is September 30!