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Cisco Unified IP Phone 8961, 9951, and 9971 Administration Guide for Cisco Unified Communications Manager 8.5 (SIP)
OL-20861-01 
Chapter 1      An Overview of the Cisco Unified IP Phone
  What Networking Protocols are Used?
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
Hypertext Transfer 
Protocol Secure (HTTPS)
Hypertext Transfer Protocol Secure 
(HTTPS) is a combination of the 
Hypertext Transfer Protocol with the 
SSL/TLS protocol to provide encryption 
and secure identification of servers.
Web applications with both HTTP and HTTPS 
support have two URLs configured. Cisco Unified 
IP Phones that support HTTPS choose the HTTPS 
URL.
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 
following authentication methods: EAP-FAST, 
EAP-TLS, and EAP-MD5.
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 1-22 for additional information.
IEEE 802.11a/b/g The IEEE 802.11 standard specifies how 
devices communication over a wireless 
local area network (WLAN).
802.11a operates at the 5 GHz band and 
802.11b and 802.11g operate at the 2.4 
GHz band 
(Cisco Unified IP Phone 9971 only) The 802.11 
interface is a deployment option for cases when 
Ethernet cabling is unavailable or undesirable.
Internet Protocol (IP) IP is a messaging protocol that addresses 
and sends packets across the network.
To communicate using IP, network devices must 
have an assigned IP address, subnet, and gateway. 
IP addresses, subnets, and gateways identifications 
are automatically assigned if you are using the 
Cisco Unified IP Phone with Dynamic Host 
Configuration Protocol (DHCP). If you are not 
using DHCP, you must manually assign these 
properties to each phone locally.
Link Layer Discovery 
Protocol (LLDP)
LLDP is a standardized network discovery 
protocol (similar to CDP) that is supported 
on some Cisco and third-party devices. 
The Cisco Unified IP Phone supports LLDP on the 
PC port.
Table 1-4 Supported Networking Protocols on the Cisco Unified IP Phone (continued)
Networking Protocol Purpose Usage Notes