# SIP trunk to another PBX

Section export for this drawing.

## Sources and go deeper

Independent, free, learning-only student project.

Opened 2026-10. A row marked confirm has no link, because that page was not verified.

- Wikipedia. [SIP trunking (Wikipedia)](https://en.wikipedia.org/wiki/SIP_trunking). last checked 2026-10
- SIP Forum. [SIPconnect technical recommendation](https://www.sipforum.org/technology/sipconnect/). last checked 2026-10
- RFC. [RFC 3261, SIP](https://www.rfc-editor.org/rfc/rfc3261). last checked 2026-10
- Cisco. [Cisco Unified Communications Manager product support](https://www.cisco.com/c/en/us/support/unified-communications/unified-communications-manager-callmanager/series.html). last checked 2026-10
- Cisco. [System Configuration Guide for CUCM, Release 15](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/15/systemConfig/cucm_b_system-configuration-guide-15.html). last checked 2026-10

Room or sheet file: sources/pbx-trunk/sources.json