System information
System Administration Guide
ο Edit Gateway IP – Gateway IP address that corresponds to the static IP address of the remote site.
5. Port forward through the Firewall at the remote site. Items that need to be port forwarded each time a
new phone is added to the remote site are listed below:
ο The phone’s Static IP address.
ο SIP port.
ο RTP port range.
ο BLF port 2088 (Only needs to be forwarded once).
Global Local Protocol IP Address
2088 2088 UDP 192.168.2.7
5060 5060 UDP 192.168.2.7
5061 5061 UDP 169.168.2.8
16384 - 16393 16384 - 16393 UDP 192.168.2.7
16394 - 16403 16394 - 16403 UDP 192.168.2.8
Phones at Different Remote Sites each with a Firewall
When there are phones each at different remote locations and all behind their own NAT firewalls, there may
be problems passing audio between them when one remote phone calls another remote phone.
Solution: Statically map (one to one) the remote phone’s RTP ports through the NAT firewall. This requires a
few steps:
1. The first step is to identify and possibly change the RTP ports used by the phone. Normally, a large
range of ports are used. However, setting up a one to one mapping in the firewall may be a time
consuming manual operation, you will want to reduce the number of ports used.
2. Go to the Phone Options section of the Phone System / Handsets / View Configuration page for the
Allworx remote IP phone. The RTP Media Port Range parameter is the range of ports to be used by this
phone. This is configurable.
300 Main Street • East Rochester, NY 14445 • Toll Free 1-866-ALLWORX • 585-421-3850 • www.allworx.com
3. Two ports are required for each active conversation on the phone. The phone’s intercom capability
counts as a conversation. A conference call uses two ports for each remote caller. There are reasons
why having a bigger range than necessary is good. However, when you have to manually map the ports
through a firewall, you will want to dramatically reduce the large default range to something you are
willing to type into your firewall configuration. A suitable number would be 10 ports.
© 2007 InSciTek Microsystems, Inc. All rights reserved. Allworx is a registered trademark of InSciTek Microsystems.
Revised: March 28, 2007
Page 64