Aastra Telecom REV 06 - Manual (Page 127)

Features in Release 2.2
RN-001029-00, Rev 06, Release 2.2 123
5i Series IP Phone Release Notes
RPORT Support
The Session Initiation Protocol (SIP) operates over UDP and TCP. When used
with UDP, responses to requests are returned to the source address from which the
request came, and returned to the port written into the topmost “Via” header of the
request. However, this behavior is not desirable when the client is behind a
Network Address Translation (NAT) or firewall.
A new parameter created for the “Via” header called “Rport” in RFC 3581,
allows a client to request that the server send the response back to the source IP
address and the port from which the request came.
When you enable “Rport, the phone always uses symmetric signaling (listens on
the port used for sending requests).
An Administrator can configure “Rport” using the configuration files or the
Aastra Web UI.
3 The “Local SIP TLS Port” field has a default value of 5061. Change this value if required to a value
greater than 1024 and less than 65535.
Note: It is recommended that you avoid the conflict with any TCP ports being used. For example:
WebUI HTTP server on 80/tcp and HTTPS on 443/tcp.
4 Click to save your changes.
Aastra Web UI