Cisco SPA942 - Cisco - IP Phone User Manual

Configuring SIP, SPCP, and NAT
Network Address Translation (NAT) and Cisco IP Phones
114 Cisco SPA and Wireless IP Phone Administration Guide
5
STEP 9 Back in the SIP tab, select yes in the STUN Test Enable drop-down box.
View the debug messages to determine if your network uses symmetric NAT. Look
for the Warning header in REGISTER messages, for example, Warning: 399 Spa
“Full Cone NAT detected.”
STEP 10 Click Submit All Changes.

Cisco SPA942 - Cisco - IP Phone Specifications

General

Brand	Cisco
Model	SPA942 - Cisco - IP Phone
Category	IP Phone
Language	English