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Cisco Unified IP Phone 7975G Administration Guide for Cisco Unified Communications Manager 7.0 (SCCP and SIP)
OL-15790-01
Chapter 1 An Overview of the Cisco Unified IP Phone
What Networking Protocols Are Used?
Related Topics
•
Understanding Interactions with Other Cisco Unified IP Communications Products, page 2-1
•
Understanding the Phone Startup Process, page 2-7
•
Network Configuration Menu, page 4-5
Session Initiation Protocol
(SIP)
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.
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.
You can configure the Cisco Unified IP Phone
to use either SIP or Skinny Client Control
Protocol (SCCP).
Skinny Client Control
Protocol (SCCP)
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.
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).
Session Description Protocol
(SDP)
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.
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.
Transmission Control
Protocol (TCP)
TCP is a connection-oriented transport
protocol.
Cisco Unified IP Phones use TCP to connect
to Cisco Unified Communications Manager
and to access XML services.
Transport Layer Security
(TLS)
TLS is a standard protocol for securing and
authenticating communications.
When security is implemented, Cisco
Unified IP Phones use the TLS protocol when
securely registering with Cisco
Unified Communications Manager.
Trivial File Transfer Protocol
(TFTP)
TFTP allows you to transfer files over the
network.
On the Cisco Unified IP Phone, TFTP enables
you to obtain a configuration file specific to
the phone type.
TFTP requires a TFTP server in your network,
which can be automatically identified from
the DHCP server. If you want a phone to use
a TFTP server other than the one specified by
the DHCP server, you must manually assign
TFTP server by using the Network
Configuration menu on the phone.
User Datagram Protocol
(UDP)
UDP is a connectionless messaging protocol
for delivery of data packets.
Cisco Unified IP Phones transmit and receive
RTP streams, which utilize UDP.
Table 1-1
Supported Networking Protocols on the Cisco Unified IP Phone (continued)
Networking Protocol
Purpose
Usage Notes