Cisco 7945G Administration Manual page 20

What Networking Protocols Are Used?
Table 1-1 Supported Networking Protocols on the Cisco Unified IP Phone (continued)
Networking Protocol
Link Layer Discovery
Protocol-Media
Endpoint Devices
(LLDP-MED)
Cisco Peer-to-Peer
Distribution Protocol
(CPPDP)
Real-Time Control
Protocol (RTCP)
Real-Time Transport
Protocol (RTP)
Session Initiation
Protocol (SIP)
Skinny Client Control
Protocol (SCCP)
Session Description
Protocol (SDP)
Cisco Unified IP Phone 7965G and 7945G Administration Guide for Cisco Unified Communications Manager 6.1(3)
1-6
Purpose
LLDP-MED is an extension of the
LLDP standard developed for voice
products.
CPPDP is a Cisco proprietary
protocol used to form a peer-to-peer
hierarchy of devices. CPPDP is also
used to copy firmware or other files
from peer devices to neighboring
devices.
RTCP works with Real-Time
Transport Protocol (RTP) to provide
QoS data (such as jitter, latency, and
round trip delay) on RTP streams.
RTP is a standard protocol for
transporting real-time data, such as
interactive voice and video, over data
networks.
SIP is the Internet Engineering Task
Force (IETF) standard for
multimedia conferencing over IP.
SIP is an ASCII-based
application-layer control protocol
(defined in RFC 3261) that can be
used to establish, maintain, and
terminate calls between two or more
endpoints.
SCCP includes a messaging set that
allows communications between call
control servers and endpoint clients
such as IP Phones. SCCP is
proprietary to Cisco Systems.
SDP is the portion of the SIP protocol
that determines which parameters are
available during a connection
between two endpoints. Conferences
are established by using only the SDP
capabilities that are supported by all
endpoints in the conference.
Chapter 1 An Overview of the Cisco Unified IP Phone
Usage Notes
The Cisco Unified IP Phone uses LLDP-MED to
communicate information such as:
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/technologie
s_white_paper0900aecd804cd46d.shtml
CPPDP is used by the Peer Firmware Sharing feature.
RTCP is disabled by default, but you can enable it on a per
phone basis by using Cisco Unified Communications
Manager Phone Configuration. For more information, see
the "Network Configuration" section on page
Cisco Unified IP Phones use the RTP protocol to send and
receive real-time voice traffic from other phones and
gateways.
Like other VoIP protocols, SIP is designed to address the
functions of signaling and session management within a
packet telephony network. Signaling allows call
information to be carried across network boundaries.
Session management provides the ability to control the
attributes of an end-to-end call.
Cisco Unified IP Phones use SCCP for call control. You can
configure the Cisco Unified IP Phone to use either SCCP or
Session Initiation Protocol (SIP).
SDP capabilities, such as codec types, DTMF detection, and
comfort noise, are normally configured on a global basis by
Cisco Unified Communications Manager or Media
Gateway in operation. Some SIP endpoints may allow these
parameters to be configured on the endpoint itself.
4-26.
OL-17755-01