VP-12, VP-12P IP phones. Operation manual
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•
Public IP Address
– this parameter is used as an external address of the device when it operates behind
the NAT (gateway). As a public address, you may specify an external address (WAN) of a gateway (NAT)
that VP-12(P) operates through. At that, on the gateway (NAT), you should forward the corresponding
SIP and RTP ports used by the device.
•
Use SIP Display Name in Register
– when selected, use username in 'SIP Display Info' field of the
'Register' message.
•
Ringback at 183 Progress
– when selected, 'ringback' tone will be sent upon receiving '183 Progress'
message (w/o enclosed SDP).
•
100rel
– use reliable provisional responses (RFC3262):
•
Supported
– reliable provisional responses are supported;
•
Required
– reliable provisional responses are mandatory;
•
Off
– reliable provisional responses are disabled.
SIP protocol defines two types of responses for connection initiating requests (INVITE)—provisional
and final. 2
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, 3
хх
, 4
хх
, 5
хх
and 6
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-class responses are final and their transfer is reliable, with ACK
message confirmation. 1
хх
-class responses, except for '100 Trying' response, are provisional, without
confirmation (RFC3261). These responses contain information on the current INVITE request
processing step, therefore loss of these responses is unacceptable. Utilization of reliable provisional
responses is also stated in SIP (RFC3262) protocol and defined by '100rel' tag presence in the
initiating request. In this case, provisional responses are confirmed with PRACK message.
100rel setting operation for outgoing communications:
•
Supported
– send the following tag in 'INVITE' request—supported:100rel. In this case,
communicating gateway may transfer provisional responses reliably or unreliably –
as it deems fit;
•
Required
– send the following tags in 'INVITE' request—supported: 100rel and
required:100rel. In this case, communicating gateway should perform reliable transfer
of provisional replies. If communicating gateway does not support reliable provisional
responses, it should reject the request with message 420 and provide the following
tag—unsupported: 100rel. In this case, the second INVITE request will be sent without
the following tag—required: 100rel.
•
Off
– do not send any of the following tags in INVITE request—supported: 100rel and
required: 100rel. In this case, communicating gateway will perform unreliable transfer
of provisional replies.
100rel setting operation for incoming
communications
:
•
S
upported,
Required
– when the following tag is received in 'INVITE' request—
supported: 100rel, or required: 100rel—perform reliable transfer of provisional replies.
If there is no supported: 100rel tag in INVITE request, the gateway will perform
unreliable transfer of provisional replies.
•
Off
– when the following tag is received in 'INVITE' request—required: 100rel, reject
the request with message 420 and provide the following tag—unsupported: 100rel.
Otherwise, perform unreliable transfer of provisional replies.
•
Timer Enable
– when selected, the 'timer' (RFC 4028) extension support is enabled. When connection is
established, and both sides support 'timer' extension, one of them periodically sends re-INVITE requests
for connection monitoring purposes (if both sides support UPDATE method, wherefore it should be
If you use different STUN settings on the different accounts, be sure that SIP ports are different as well.
