Administrator's Guide

Chapter 10. SIP Services

Remote NAT Traversal

If your SIP client is not STUN-capable, you can use the built-in Remote NAT traversal fea-

ture of the Telecommuting Module. The client must register on the Telecommuting Module

(or through it).

The SIP client needs to re-REGISTER, or respond to OPTIONS packets, rather often for this

to work. The exact period for this depends on the NAT-ing device, but 20 seconds should be

enough to get across most NAT boxes.

Remote NAT traversal

Switch this function on or off.

Remote Clients Signaling Forwarding

Many SIP servers need to separate signaling to and from remote clients from signaling to

and from the SIP Trunk. For this purpose, you can specify which IP address and port the

remote clients will connect to. This can’t be the same IP address and port as what the SIP

provider uses!

You also specify which IP address the Telecommuting Module will use when it forwards this

SIP signaling to the server on the LAN. In this way, the trunk signaling and remote client

signaling will be separated for the PBX.

IP Address for Remote Clients

Select which IP address remote clients connect to. This can be the same IP address as is used

by the SIP provider, but then you need to select a different signaling port below.

IP Port for Remote Clients

Enter the signaling port to which remote SIP clients should connect. The Telecommuting

Module will listen for SIP signaling on this port only for the IP address selected above.

If you select an alias IP address as the address to where remote clients should connect, you

can’t enter a port, but must use port 5060 (5061 for TLS connections). If you select an IP

address that was entered in the Directly Connected Networks table, you must specify a

port.

You cannot select a port that is already in use for something else, or speciﬁed in the Addi-

tional SIP Signaling Ports table.

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