/mcpare the same. In a three-or-more-hop case, the intermediate parties do not get communicated to the current forwarded-to party. For example: Diversion: "Line 1020 Name" sip:1020@172.18.203.99;reason=no-answer;privacy=off;screen=yes Diversion: "Line 2020 Name" sip:2020@172.18.203.99;reason=unconditional;privacy=off;screen=yes Diversion: "Line 3020 Name" sip:3020@172.18.203.99;reason=user-busy;privacy=off;screen=yes The phone may activate Call Forward All via a softkey. Message Waiting Indication The system triggers activation of the Message Waiting Indication (MWI) on the phone via an unsolicited NOTIFY from Unified CM. The NOTIFY has an event type of “message-summary” and a message body with content type of “application/simple-message-summary” and a body that contains either “Messages-Waiting: yes” to instruct the phone to turn on its MWI or “Messages-Waiting: no” to instruct the phone to turn off its MWI. This MWI Notify will get sent whenever that Unified CM detects that the phone MWI status should change. This could occur if a message is left for that subscriber on a connected voice messaging server and that voice messaging server informs Unified CM or if all messages are cleared. Also, this NOTIFY that contains the current MWI state always gets sent during registration of a line, so phones with flash memory have the latest MWI state that is known to Unified CM. Endpoint Returns 302 Redirect Because not all SIP phones support the enhanced call forward all activation behavior to synchronize the call forward all state between the phone and Unified CM, some phones may allow the user to configure a call forward number on the phone locally and then return a 302 message to an INVITE instead. The 302 message must contain a “Contact:” header that indicates the party to which the call should be forwarded. A phone that sends a 302 should also include a “Diversion:” header that includes its own name and number as well as the reason for forwarding. When Unified CM receives a 302 message from a phone, the system presents the call to the next party that is indicated in the contact header of that 302 with the diversion header from the 302 that is listed first (assuming the next party is also a SIP device). If that next party also forwards, the diversion header that is sent in the first 302 may get passed along to subsequent forwarded-to parties if the phone that is sending the 302 was the original called party. SIP Line Messaging Guide (Standard Edition) for Cisco Unified Communications Manager 31 SIP Standard Line Interface Message Waiting Indication