We are running into an issue where our polycoms are subscribing at half of the agreed Expires. The server accepts the expiration of 3600 seconds, but the device is sending another subscribe after 1800 seconds. These devices are running 3.1.2. What setting in the cfg files control the subscribe expiration and could contribute to the half-life re-Subscribe?
Polycom to SIP Server
Via: SIP/2.0/UDP xxx.xxx.xxx.xxx;branch=z9hG4bK46d78e29CDE718B8
From: "User" <sip:user@xxx.xxx.xxx.xxx>;tag=9E59AD29-69AC93B8
To: <sip:userb@xxx.xxx.xxx.xxx>;tag=SDh6f4099-as62909215
CSeq: 3 SUBSCRIBE
Call-ID: 7f81e804-31c5285f-c270886@xxx.xxx.xxx.xxx
Contact: <sip:user@xxx.xxx.xxx.xxx>
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, INFO, MESSAGE, SUBSCRIBE, NOTIFY, PRACK, UPDATE, REFER
Event: presence
User-Agent: PolycomSoundPointIP-SPIP_650-UA/3.1.2.0392
Accept-Language: en
Accept: application/xpidf+xml,text/xml+msrtc.pidf
Max-Forwards: 70
Expires: 3600
Content-Length: 0
SIP Server to Polycom
Via: SIP/2.0/UDP xxx.xxx.xxx.xxx;received=xxx.xxx.xxx.xxx;branch=z9hG4bK7e606632C79C31A;rport=1033
From: "User" <sip:user@xxx.xxx.xxx.xxx>;tag=9E59AD29-69AC93B8
To: <sip:userb@xxx.xxx.xxx.xxx>;tag=SDh6f4099-as62909215
CSeq: 4 SUBSCRIBE
Call-ID: 7f81e804-31c5285f-c270886@xxx.xxx.xxx.xxx
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Expires: 3600
Contact: <sip:userb@xxx.xxx.xxx.xxx;transport=udp>;expires=3600
Content-Length: 0