Installation guide

Network Settings
41-001561-00 REV00 – 10.2014 4-25
SIP and TLS Source Ports for NAT Traversal
A System Administrator can configure the SIP and TLS source ports on the IP Phone. Previously, the IP phone used default
values (5060 for UDP/TCP and 5061 for TLS). The two new parameters for configuring the SIP and TLS source ports are:
• sip local port
• sip local tls port
You can configure the SIP and TLS source ports using the configuration files or the Mitel Web UI. After configuring these
parameters, you must reboot the phone.
If NAT is disabled, the port number also shows in the VIA and Contact SIP headers.
If you enable NAT, the phone uses the NAT port number (and NAT IP address) in the Via and Contact SIP headers of SIP
messages, but still use the configured source port.
Mitel Web UI
1. Click on Advanced Settings->Network->Advanced Network Settings.
2. Enter a NAT IP address in the "NAT IP" field. The value must be entered in dotted decimal format.
For example, 0.0.0.0. The “NAT IP” is the public IP address of your NAT device.
3. Enter a NAT port in the "NAT SIP Port" field. Default is 51620.
The “NAT SIP Port” is the public SIP signaling port number of your NAT device.
4. Enter a NAT port in the "NAT RTP Port" field. Default is 51720.
The “NAT RTP Port” is the RTP Port number of your NAT device.
5. Click Save Settings to save your settings.
Note:
• By default, the IP phones use symmetric UDP signaling for outgoing UDP SIP messages. When symmetric UDP is ena-
bled, the IP phone generates and listens for UDP messages using port 5060.If symmetric UDP signaling is disabled,
the phone sends from random ports but it listens on the configured SIP local port. Refer to Symmetric UDP Signaling
on page 6-23 for more information.
• The IP phones also use symmetric TLS signaling for outgoing TLS SIP messages by default. When symmetric TLS is
enabled, the IP phone uses port 5061 as the persistent TLS connection source port. When symmetric TLS signaling is
disabled, the IP phone chooses a random persistent TLS connection source port for TLS messages from the TCP range
(i.e. 49152...65535) after each reboot regardless of whether the parameter “sip outbound support” is enabled or dis-
abled. Refer to Symmetric TLS Signaling on page 6-23 for more information.