Sip Session Timer (S); Dirty Host Ttl (S); Sip Max Forwards; Enum Suffix - Snom 360 Manual

Call Register
SIP T1 (ms)
Set the re-try timer in milliseconds after which an unanswered request
is resend again. In case its set to 500, the phone will resend the
unanswered request after 500, 1000, 2000, 4000, 6000...31500 ms. Is
the request still unanswered after this procedure an error message is
shown at the display.

SIP Session Timer (s)

A user can specify the session timer for SIP in seconds here. For
instance a Re-INVITE will be send after its expiration.

Dirty Host TTL (s)

Specify the "Time to Live" (TTL) for dirty hosts in seconds through this
setting. This means a host which couldn't be reached from the phone is
set onto this list so the phone will not try to reach this host again until
the here specified time elapsed.

SIP Max Forwards

If you want to specify the maximum number of forwards, you can set it
here. This prevents the phone to run into a SIP message forwarding
loop. On each forward the counter given here is reduced by one and if
zero is reached the forwarding will be stopped.

ENUM Suffix

When using ENUM, you can specify a service suffix here, if desired.
There is more than one service available which supports ENUM lookups
and here you can select which one you want to use. Leave the default
value e164.arpa in case you don't know.
Use user=phone
Turn this setting on if you want to use user=phone in SIP URIs. This is
to distinguish a phone from a different non phone device like a gateway
etc (RFC2543 depricated). Select "off" to disable it.
Publish Presence
Control the "presence" status information through this setting. The
phone sends out PUBLISH messages showing the phone status in case
of "on".
Refer-To Brackets
To switch additional brackets on or off in the Signaling for Refer-To.
Some devices are relying on this, so we are nice and offering a solution!
Require PRACK
To force the usage of PRACK, choose "on" here. "PRACK" messages are
used to acknowledge the receiving of "180 Ringing" messages which are
usually not acknowledged. This helps for example to inform gateways if
the phone really began to ring already.
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