Polycom SIP 2.2.0 ユーザーズマニュアル

 Configuring Your System

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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.

In situations where server redundancy for fall-back purpose is used, the 

following measures should be taken to optimize the effectiveness of the 

solution:

Deploy an on-site DNS server to avoid long call initiation delays that can 

result if the DNS server records expire.

Do not use OutBoundProxy configurations on the phone if the 

OutBoundProxy could be unreachable when the fallback occurs. 

SoundPoint IP phones can only be configured with one OutBoundProxy 

per registration and all traffic for that registration will be routed through 

this proxy for all servers attached to that registration. If Server 2 is not 

accessible through the configured proxy, call signaling with Server 2 will 

fail.

Avoid using too many servers as part of the redundancy configuration as 

each registration will generate more traffic.

Educate users as to the features that will not be available when in 

“fallback” operating mode.

The Presence feature allows the phone to monitor the status of other 

users/devices and allows other users to monitor it. The status of monitored 

users is displayed visually and is updated in real time in the Buddies display 

screen or, for speed dial entries, on the phone’s idle display. Users can block 

others from monitoring their phones and are notified when a change in 

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.