0x2957 SIP Request URI User Information Qualifier

Use this TLV to append a user-defined ASCII string to the Request URI user name in outbound SIP calls from the CSP. Specifically, the ASCII string is populated in the user information of the Request-URI header in the outbound SIP INVITE message.

When the CSP is in a SIP/PSTN gateway environment, you can use this TLV to report the terminating trunk group information in a
PSTN-to-SIP call.

If the host provides the Request URI parameters, it must also provide the "To Header" parameters. (See TLVs 0x2919, 0x291A, 0x291B, and 0x291C).

Used in:
0x0033 NPDI Universal ICB in:
Route Control message
Outseize Control message

Byte | Description
0, 1 | Tag 0x2957
2, 3 | Length Variable
4-7 | Value[0-n] Null-terminated ASCII string

Tag-Length-Value block. A standardized block that allows data to inserted in a standard way into API messages.
American Standard Code for Information Interchange
Session-Initiation Protocol. A signaling protocol used for establishing sessions in an IP network. A session could be a simple, two-way telephone call, or it could be a collaborative multi-media conference session.
Public Switched Telephone Network
Network Protocol Data Intelligence. Also called “Interworking,” it is a software product that operates within Excel’s Call Control (Layer 4) and Services (Layer 5) call processing layers. NPDI is meant to enhance Excel’s call processing product offering by allowing call processing layers (specifically Layers 4 and 5) to perform advanced analysis, generation, and conversion of Network Signaling (NS) Layer 3 information.
See Information Control Block.
Outgoing call setup during real-time call processing on a specific channel.