This is a module to help with NAT traversal and reuse of TCP connections. In particular, it helps symmetric UAs that don't advertise they are symmetric and are not able to determine their public address. The function fix_nated_contact() rewrites the “Contact” header field with request's source address:port pair. The function fix_nated_sdp() adds the active direction indication to SDP (flag 0x01) and updates the source IP address too (flag 0x02). The function fix_nated_register() exports the request's source address:port into an AVP to be used during save() and should be used for “REGISTER” requests. Note: fix_nated_contact() changes the “Contact” header, thus it breaks the RFC. Although this is not always an issue, it may cause problems with strict SIP clients. An alternative is to use add_contact_alias() (or set_contact_alias()) that together with the handle_ruri_alias() is standards conforming and also supports reuse of TCP/TLS connections.
Copyright © 2003-2008 Sippy Software, Inc.
Copyright © 2005 Voice Sistem SRL
Copyright © 2009 TuTPro Inc.
Copyright © 2010 VoIPEmbedded Inc.
