User's Manual

Chapter 18 Maintenance and Troubleshooting
Resolving problems
SmartClass TPS User’s Guide
May 2014 22035456, Rev 001 155
If you are on an IPoE line and STUN is enabled, the data layer will not come up until the STUN client
on the SmartClass has determined the type of NAT used between the SmartClass and the STUN
server. Wait a few minutes and try to resync.
Check with your system administrator to verify that the firewall allows VoIP traffic.
Issue
I am emulating a SIP phone but cannot register with the SIP server.
Resolution
In typical networks, the same server handles both registration and placing and receiving calls.
However, in some networks, there is a Proxy server that handles SIP messaging for placing and
receiving calls, and a registrar that handles registration, which may be in a different domain.
If this is the case, do the following.
– Verify that you specified the “Proxy” on the Proxy Settings menu as the outbound proxy, or the
device from which the SmartClass will send and receive all SIP messages (for placing and
receiving calls).
– Verify that you specified the “Alias” on the General Settings menu as the SIP server or registrar
(the device that keeps track of all the registered devices), using the following format “phone-
Number@domain” where domain is either an IP address of the registrar or a literal domain
such as “jdsu.com”.
Issue
The VoIP delay measurement does not appear.
Resolution
The Delay result is only calculated if the RTCP signaling is active.
Issue
I have very little loss, but a high level of delay.
Resolution
Check your network. It may be experiencing high traffic.
Issue
I have a large amount of jitter, but no loss or delay.
Resolution
Check the setup of your router.