Polycom Video Game Sound System Version 2.0.3B User Manual

Page of 42
Technical Bulletin
SoundPoint 
®
 IP, SIP 2.1
4
Phone Configuration
The phones at the customer site are configured as follows:
• Server 1 (the primary server) will be configured with the address of the 
service provider call server. The IP address of the server(s) to be used will 
be provided by the DNS server. For example:
reg.1.server.1.address="voipserver.serviceprovider.com"
• Server 2 (the fallback server) will be configured to the address of the 
router/gateway that provides the fallback telephony support and is 
on-site. For example:
reg.1.server.2.address=172.23.0.1
Phone Operation for Registration
After the phone has booted up, it will register to all the servers that are 
configured.
Server 1 is the primary server and supports greater SIP functionality than any 
of servers. For example, SUBSCRIBE/NOTIFY services (used for features such 
as shared lines, presence, and BLF) will only be established with Server 1.
Upon registration timer expiry of each server registration, the phone will 
attempt to re-register. If this is unsuccessful, normal SIP re-registration 
behavior (typically at intervals of 30 to 60 seconds) will proceed and continue 
until the registration is successful (for example, when the Internet link is once 
again operational). While the primary server registration is unavailable, the 
next highest priority server in the list will serve as the working server. As soon 
as the primary server registration succeeds, it will return to being the working 
server.
Note
It is possible to configure the phone for more than two servers per registration, but 
you need to exercise caution when doing this to ensure that the phone and network 
load generated by registration refresh of multiple registrations do not become 
excessive. This would be of particularly concern if a phone had multiple 
registrations with multiple servers per registration and it is expected that some of 
these servers will be unavailable.
Note
If reg.x.server.y.register is set to 0, then phone will not register to that server. 
However, the INVITE will fail over to that server if all higher priority servers are 
down.