Cisco Systems 6921 manual See the LLDP-MED and Cisco Discovery Protocol, White paper, Sip

Chapter

What Networking Protocols are Used?

Table 1-4	Supported Networking Protocols on the Cisco Unified IP Phone (continued)
Networking Protocol		Purpose	Usage Notes
Link Layer Discovery		LLDP-MED is an extension of the LLDP	The Cisco Unified IP Phone supports LLDP-MED
Protocol-Media Endpoint		standard developed for voice products.	on the SW port to communicate information such as:
Devices (LLDP-MED)			•	Voice VLAN configuration
			•	Device discovery
			•	Power management
			•	Inventory management
			For more information about LLDP-MED support,
			see the LLDP-MED and Cisco Discovery Protocol
			white paper:
			http://www.cisco.com/en/US/tech/tk652/tk701/tech
			nologies_white_paper0900aecd804cd46d.shtml
Real-Time Transport		RTP is a standard protocol for transporting	Cisco Unified IP Phones use the RTP protocol to
Protocol (RTP)		real-time data, such as interactive voice	send and receive real-time voice traffic from other
		and video, over data networks.	phones and gateways.
Real-Time Control		RTCP works in conjunction with RTP to	RTCP is disabled by default, but you can enable it
Protocol (RTCP)		provide QoS data (such as jitter, latency,	on a per phone basis by using Cisco Unified CM.
		and round trip delay) on RTP streams.
Session Initiation Protocol		SIP is the Internet Engineering Task Force	Like other VoIP protocols, SIP is designed to
(SIP)		(IETF) standard for multimedia	address the functions of signaling and session
		conferencing over IP. SIP is an	management within a packet telephony network.
		ASCII-based application-layer control	Signaling allows call information to be carried
		protocol (defined in RFC 3261) that can be	across network boundaries. Session management
		used to establish, maintain, and terminate	provides the ability to control the attributes of an
		calls between two or more endpoints.	end-to-end call.
			You can configure the Cisco Unified IP Phone to use
			either SIP or Skinny Client Control Protocol
			(SCCP). Cisco Unified IP Phones do not support the
			SIP protocol when the phones are operating in IPv6
			address mode.
Skinny Client Control		SCCP includes a messaging set that allows	Cisco Unified IP Phone 6921, 6941, 6945, and 6961
Protocol (SCCP)		communications between call control	use SCCP, version 20 for call control.
		servers and endpoint clients such as
		IP Phones. SCCP is proprietary to Cisco
		Systems.
Secure Real-Time		SRTP is an extension of the Real-Time	Cisco Unified IP Phones use SRTP for media
Transfer protocol (SRTP)		Protocol (RTP) Audio/Video Profile and	encryption.
		ensures the integrity of RTP and
		Real-Time Control Protocol (RTCP)
		packets providing authentication,
		integrity, and encryption of media packets
		between two endpoints.
Transmission Control		TCP is a connection-oriented transport	Cisco Unified IP Phones use TCP to connect to
Protocol (TCP)		protocol.	Cisco Unified CM and to access XML services.

Cisco Unified IP Phone 6921, 6941, 6945, and 6961 Administration Guide for Cisco Unified Communications Manager 8.5 (SCCP and SIP)

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