Cisco 8831NR Administration Manual page 27

Cisco Unified IP Conference Phone 8831 and 8831NR
Networking Protocol
Real-Time Transport Protocol
(RTP)
Real-Time Control Protocol
(RTCP)
Session Initiation Protocol (SIP)
Secure Real-Time Transfer
Protocol (SRTP)
Transmission Control Protocol
(TCP)
Transport Layer Security (TLS)
Purpose
RTP is a standard protocol for
transporting real-time data, such as
interactive voice and video, over
data networks.
RTCP works in conjunction with
RTP to provide QoS data (such as
jitter, latency, and round trip delay)
on RTP streams.
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.
SRTP is an extension of the
Real-Time Protocol (RTP)
Audio/Video Profile and ensures
the integrity of RTP and Real-Time
Control Protocol (RTCP) packets
providing authentication, integrity,
and encryption of media packets
between two endpoints.
TCP is a connection-oriented
transport protocol.
TLS is a standard protocol for
securing and authenticating
communications.
Cisco Unified IP Conference Phone 8831 and 8831NR Administration Guide
Network Protocols
Usage Notes
Cisco Unified IP Phones use the
RTP protocol to send and receive
real-time voice traffic from other
phones and gateways.
RTCP is disabled by default, but
you can enable it on a per phone
basis by using Cisco Unified
Communications Manager.
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 SRTP
for media encryption.
Cisco Unified IP Phones use TCP
to connect to Cisco Unified
Communications Manager and to
access XML services.
When security is implemented,
Cisco Unified IP Conference Phone
use the TLS protocol when securely
registering with Cisco Unified
Communications Manager.
For more information, see Cisco
Unified Communications Manager
Security Guide.
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