McDewey

There are two sets of identities: network provided identity (trusted) and user provided identity (untrusted). In terms of SIP calls, Identity headers including P-Asserted-Identity (PAI), P-Preferred-Identity (PPI), and Remote-Party-ID (RPID) should carry network proven identity while From header carries user/caller provided identity. Previously, Unified CM only provides a single set of identity for outgoing calls. Therefore, the identities in Identity headers and From header are the same and there is no differentiation between network provided identity and user provided identity. Typically, administrators configure each user device with a Directory Number (DN) and a display name. An outgoing call from this DN carries its directory number and display name in both the Identity headers and From header. The administrator can also configure another identity on a SIP trunk. You can use this identity, sometimes termed as a switchboard, to hide each individual caller's identity. You can configure it on the Caller Information section of a SIP Trunk for outbound calls. The configuration includes two fields, Caller ID DN and Caller Name. For example, all calls originating from a SIP Trunk carry the same identify, Caller Name with "Cisco Systems" and "(800) 555-1234" for the Caller ID DN. However, the caller's original directory number and display name will be overwritten when you enable such configurations. With this new feature, however, Unified CM provides configurations where the administrator can enable both sets of identifications, switchboard identity and original caller identity. Switchboard identity will be carried in the From header and original caller identity will be carried in the Identity headers. You can enable this configuration for each SIP Trunk or SIP device. For incoming calls, Unified CM provides configurations to accept network provided identity carried in Identity headers or user provided identity carried in the From header. Unified CM maintains only a single set of identities per call. URI Dialing The URI Dialing feature gives Unified Communications Manager the ability to route an alphanumeric URI, such as bob@cisco.com, and allows the delivery of both URI and DN in identity headers for endpoints that supports both. The following use case shows a URI intra-cluster call and presumes that blended delivery is enabled and the phones can consume. 1. Phone A dials bob@cisco.com. Unified CM discovers blended info, for calling and called parties 1000/bob@cisco.com, 2000/alice@cisco.com. 2. Unified CM extends INVITE to Phone B. Since phone B is configured to consume blended identity info, the RPID contains blended. 3. Phone extends Alerting, RPID from phone is ignored. Unified CM will re-blend with 1000/bob@cisco.com. 4. Unified CM extends 180 Ringing to phone A. Since phone A is configured to consume blended identity info, the RPID contains blended. SIP Line Messaging Guide (Standard Edition) for Cisco Unified Communications Manager 38 SIP Standard Line Interface URI Dialing