Configuring res_pjsip to work through NAT

Publisher

Sangoma / Asterisk Project

URL

https://docs.asterisk.org/Configuration/Channel-Drivers/SIP/Configuring-res_pjsip/Configuring-res_pjsip-to-work-through-NAT/

Published

unknown

Updated

unknown

Accessed

2026-09-24

HTTP status

200

License

Asterisk documentation (CC BY-SA per project site; not re-verified); no-redistribution; short excerpts and locators only

Source notes citing this source

• The Asterisk NAT configuration example sets direct_media=no on the endpoint. in context
• On a PJSIP transport, external_media_address and external_signaling_address replace Asterisk's address in SDP and SIP signaling with the given external address when the destination lies outside local_net. in context
• The PJSIP transport local_net option defines the local network, and NAT-related settings such as the external addresses are not applied to traffic within it. in context
• For phones behind a remote NAT, Asterisk documents the endpoint options rtp_symmetric, force_rport and rewrite_contact, which send RTP and SIP back to the observed source address and port. in context
• Asterisk's direct_media option controls whether media may flow directly between endpoints, rather than being anchored on Asterisk. in context
• Asterisk's external_media_address option rewrites the SDP media address to the configured external address when the message goes to a destination outside local_net and the media address in the SDP is inside local_net. in context
• Asterisk's res_pjsip rtp_symmetric option makes RTP symmetric: Asterisk sends RTP back to the address and port it received RTP from. in context

Cite this source record

APA

WarmTransfer. (2026, September 24). Configuring res_pjsip to work through NAT. WarmTransfer. https://warmtransfer.net/knowledge/sources/asterisk-docs-pjsip-nat

BibTeX

@misc{warmtransfer-asterisk-docs-pjsip-nat,
  title  = {Configuring res_pjsip to work through NAT},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/asterisk-docs-pjsip-nat},
  note   = {Sangoma / Asterisk Project, accessed 2026-09-24}
}