SIP Third Party Phone Configuration

Cisco SCCP phones register with Cisco Unified Communications Manager (CUCM) via their MAC address where SIP third party phones use digest authentication. SIP digest authentication is part of the RFC3261 SIP specification. Cisco SIP based phones have SIP extensions that use the SIP protocol for Cisco proprietary operations like registering a Cisco SIP phone by MAC Address. This blog will take a high level look at configuring a SIP third-party client. Detailed information on this topic can be found in the references link I have provided. SIP third-party endpoint configuration in Cisco Unified Communications Manager (CUCM) involves some configuration elements that are different than SCCP based phones. SCCP phones are registered by MAC address, while SIP third-party phones require the configuration of an end user that is associated to the phone as the digest authentication user on that phone. Configure an end user in CUCM administration first. When configuring the SIP third-party phone (basic or advanced), the end user previously configured will be associated to the phone as the digest user. Digest user is a drop down configuration menu when configuring the “SIP Third-Party Device (Basic)”. I normally go back to the end user configuration page and do a Device Association of the end user to the phone, but this is not a requirement for SIP third party phone registration. The end user only needs to be associated to the phone as a digest user. The SIP third party endpoint must be configured now. The SIP third party endpoint is configured in CUCM similar to a SCCP based phone, but the third party client does not get a new configuration file downloaded to it like SCCP based phones. Since there is no automatic TFTP configuration file download functionality to SIP third party clients, the SIP third party client must be configured with a SIP proxy server address of CUCM’s IP address. The digest user will also need to be configured on the SIP third party client. The next blog will cover some of the features that require a Cisco phone to be converted to SIP. REFERENCES Configuring Non-Cisco SIP Phones http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/7_1_2/ccmcfg/b09sip3p.html SIP: Session Initiation Protocol (RFC3261) http://www.ietf.org/rfc/rfc3261.txt