Hold Implementation; Reliability Of Provisional Responses; Transfer; Third Party Call Control - Polycom IP 320 Administrator's Manual

Hold Implementation

Note

Reliability of Provisional Responses

Transfer

Third Party Call Control

6xx Responses - Global Failure
Response
600 Busy Everywhere
603 Decline
604 Does Not Exist Anywhere
606 Not Acceptable
The phone supports both currently accepted means of signaling hold.
The first method, no longer recommended due in part to the RTCP problems
associated with it, is to set the "c" destination addresses for the media streams
in the SDP to zero, for example, c=0.0.0.0.
The second, and preferred, method is to signal the media directions with the
"a" SDP media attributes sendonly, recvonly, inactive, or sendrecv. The hold
signaling method used by the phone is configurable (refer to
page A-11), but both methods are supported when signaled by the remote end
point.
Even if the phone is set to use c=0.0.0.0, it will not do so if it gets any sendrecv,
sendonly, or inactive from the server. These flags will cause it to revert to the other
hold method.
The phone fully supports RFC 3262 - Reliability of Provisional Responses.
The phone supports transfer using the REFER method specified in
draft-ietf-sip-cc-transfer-05 and RFC 3515.
The phone supports the delayed media negotiations (INVITE without SDP)
associated with third party call control applications.
When used with an appropriate server, the User Agent Computer Supported
Telecommunications Applications (uaCSTA) feature on the phone may be
utilized for remote control of the phone from computer applications such as
Microsoft Office Communicator.
Session Initiation Protocol (SIP)
Supported Notes
No
Yes
No
No
SIP <SIP/>on
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