Linksys ATA Administration Guide
42
Firewalls and SIP
Configuring Your System for ITSP Interoperability
3. To enable debugging, complete the following tasks:
a. Click
Voice tab > System
.
b. In the
Debug Server
field, enter the IP address of your syslog server.
NOTE:
This address and port number must be reachable from the SPA9000.
c. From the
Debug level
drop-down list, choose
3
.
4. To collect information about the type of NAT your router is using, complete the following
tasks:
a. Click
Voice tab > SIP
.
b. Scroll down to the
NAT Support Parameters
section.
c. From the
STUN Test Enable
field, choose
yes
.
5. To enable SIP signalling, complete the following task:
a. Click
Voice tab > Line
N
, where
N
represents the line interface number.
b. In the
SIP Settings
section, choose
full
from the
SIP Debug Option
field.
6. Click
Submit All Changes
.
7. View the syslog messages to determine whether your network uses symmetric NAT. Look
for a warning header in the REGISTER messages, such as Warning: 399 spa "Full Cone NAT
Detected.”
Firewalls and SIP
To enable SIP requests and responses to be exchanged with the SIP proxy at the ITSP, you must
ensure that your firewall allows both SIP and RTP unimpeded access to the Internet.
•
Make sure that the following ports are not blocked:
–
SIP ports—UDP port 5060 through 5063, which are used for the ITSP line interfaces
–
RTP ports—16384 to 16482
•
Also disable SPI (Stateful Packet Inspection) if this function exists on your firewall.
