0x2951 SIP From Tag

Use this TLV to specify the Tag value in the From Header of the SIP message.

Used in:
Request for Service with Data message

Byte | Description
0, 1 | Tag 0x2951
2, 3 | Length Variable
4-n | Value[0-n] Null Terminated ASCII value of Call-ID header.

Tag-Length-Value block. A standardized block that allows data to inserted in a standard way into API messages.
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.
American Standard Code for Information Interchange