Figure 162 Sip Redirect Server; Sip Register Server - Nortel 252 Configuration

Figure 162 SIP Redirect Server

SIP Register Server

A SIP register server maintains a database of SIP identity-to-IP address (or
domain name) mapping. The register server checks your username and password
when you register.
RTP
When you make a VoIP call using SIP, the RTP (Real time Transport Protocol) is
used to handle voice data transfer. See RFC 1889 for details on RTP.
Nortel Business Secure Router 252 Configuration — Advanced
Appendix L SIP 337