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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?
What Networking Protocols Are Used?
Cisco Unified IP Phones support several industry-standard and Cisco networking protocols required for
voice communication.
Table 1-1
provides an overview of the networking protocols that the Cisco
Unified IP Phone 7975G supports.
Table 1-1
Supported Networking Protocols on the Cisco Unified IP Phone
Networking Protocol
Purpose
Usage Notes
Bootstrap Protocol (BootP)
BootP enables a network device such as the
Cisco Unified IP Phone to discover certain
startup information, such as its IP address.
If you are using BootP to assign IP addresses
to the Cisco Unified IP Phone, the BOOTP
Server option shows “Yes” in the network
configuration settings on the phone.
Cisco Discovery Protocol
(CDP)
CDP is a device-discovery protocol that runs
on all Cisco-manufactured equipment.
Using CDP, a device can advertise its
existence to other devices and receive
information about other devices in the
network.
The Cisco Unified IP Phone uses CDP to
communicate information such as auxiliary
VLAN ID, per port power management details,
and Quality of Service (QoS) configuration
information with the Cisco Catalyst switch.
Dynamic Host Configuration
Protocol (DHCP)
DHCP dynamically allocates and assigns an
IP address to network devices.
DHCP enables you to connect an IP phone
into the network and have the phone become
operational without your needing to manually
assign an IP address or to configure additional
network parameters.
DHCP is enabled by default. If disabled, you
must manually configure the IP address,
subnet mask, gateway, and a TFTP server on
each phone locally.
Cisco recommends that you use DHCP
custom option 150. With this method, you
configure the TFTP server IP address as the
option value. For additional information
about DHCP configurations, refer to the
“Cisco TFTP” chapter in
Cisco
Unified Communications Manager System
Guide
.
Hypertext Transfer Protocol
(HTTP)
HTTP is the standard way of transferring
information and moving documents across the
Internet and the web.
Cisco Unified IP Phones use HTTP for the
XML services and for troubleshooting
purposes.
IEEE 802.1X
The IEEE 802.1X standard defines a
client-server-based access control and
authentication protocol that restricts
unauthorized clients from connecting to a
LAN through publicly accessible ports.
Until the client is authenticated, 802.1X
access control allows only Extensible
Authentication Protocol over LAN (EAPOL)
traffic through the port to which the client is
connected. After authentication is successful,
normal traffic can pass through the port.
The Cisco Unified IP Phone implements the
IEEE 802.1X standard by providing support
for the EAP-MD5 option for 802.1X
authentication.
When 802.1X authentication is enabled on the
phone, you should disable the PC port and
voice VLAN. Refer to the
“Supporting
802.1X Authentication on Cisco Unified IP
Phones” section on page 1-15
for additional
information.