Remote Extensions

[STDSupport]

Hello everyone,

I have about 6 phones at a remote office and having a small issue. These phones register back to the parent company's PBX which are both protected with firewalls on each end. For the most part the phones during the day stay connected, voice quality is excellent, but at times especially when I come into work in the morning 1 or more phones is actually indicating Unreachable. It's as if the phones have gone to sleep and once staff on the remote end start working the phones then are reachable again. However I were to call the extension when its indicating "Unreachable" will automatically send me to voice mail.

UDP Server expires is at default 3600, Keep Alive - 30 secs, Subscription period 1800. Now one thing I have mentioned is the Yealinks are registered on an iPtitomy PBX and it always seems one of the 6 phones, is indeed an iPitomy phone it never appears to disconnect. Any suggestions are gladly welcomed, I checked the PBX and it has set Max Length of registration 7200, Default length of registration 120 and RTP Keep Alive 30.