Cisco 7975G Administration Guide

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Cisco Unified IP Phone 7975G Administration Guide for Cisco Unified Communications Manager 6.0
OL-12642-01
Chapter 1 An Overview of the Cisco Unified IP Phone
Understanding Security Features for Cisco Unified IP Phones
Supporting 802.1X Authentication on Cisco Unified IP Phones
These sections provide information about 802.1X support on the Cisco Unified IP Phones:
• Overview, page 1-16
• Required Network Components, page 1-17
• Best Practices—Requirements and Recommendations, page 1-17
Overview
Cisco Unified IP phones and Cisco Catalyst switches have traditionally used Cisco Discovery Protocol
(CDP) to identify each other and to determine parameters such as VLAN allocation and inline power
requirements. However, CDP is not used to identify any locally attached PCs. Therefore, Cisco Unified
IP Phones provide an EAPOL pass-through mechanism, whereby a PC locally attached to the IP phone
may pass through EAPOL messages to the 802.1X authenticator in the LAN switch. This capability
prevents the IP phone from having to act as the authenticator, yet allows the LAN switch to authenticate
a data end point prior to accessing the network.
In conjunction with the EAPOL pass-through mechanism, Cisco Unified IP Phones provide a proxy
EAPOL-Logoff mechanism. If the locally attached PC is disconnected from the IP phone, the LAN
switch would not see the physical link fail, because the link between the LAN switch and the IP phone
is maintained. To avoid compromising network integrity, the IP phone sends an EAPOL-Logoff message
to the switch on behalf of the downstream PC, which triggers the LAN switch to clear the authentication
entry for the downstream PC.
The Cisco Unified IP phones contain an 802.1X supplicant in addition to the EAPOL pass-through
mechanism. This supplicant allows network administrators to control the connectivity of IP phones to
the LAN switch ports. The initial release of the IP phone 802.1X supplicant implements the EAP-MD5
option for 802.1X authentication.
Secure (encrypted) Join Encrypted or
authenticated
Secure conference bridge
Conference remains secure
(encrypted or authenticated)
Non-secure cBarge All participants are
encrypted
Secure conference bridge
Conference changes to non-secure
Non-secure MeetMe Minimum security level is
encrypted
Initiator receives message “Does not
meet Security Level”, call rejected.
Secure (encrypted) MeetMe Minimum security level is
authenticated
Secure conference bridge
Conference accepts encrypted and
authenticated calls
Secure (encrypted) MeetMe Minimum security level is
non-secure
Only secure conference bridge
available and used
Conference accepts all calls
Table 1-5 Security Restrictions with Conference Calls (continued)
Initiator’s Phone
Security Level Feature Used
Security Level of
Participants Results of Action

Cisco 7975G Specifications

General

Handset type	Wired handset
Product type	IP Phone
Product color	Grey, Silver
Speakerphone	Yes
Voice codecs	G.711Mu, G.711a, G.722, G.729A, iLBC
Number of melodies	24
Aspect ratio	4:3
Display diagonal	5.6 \
Display resolution	320 x 240 pixels
Lines quantity	8 lines
Phonebook capacity	- entries
Number of VoIP accounts	-
Front camera	No
Security algorithms	128-bit AES
Networking standards	IEEE 802.1Q, IEEE 802.1p, IEEE 802.1x, IEEE 802.3af
Ethernet LAN data rates	10, 100, 1000 Mbit/s
Ethernet LAN interface type	Gigabit Ethernet
Supported network protocols	DHCP, TFTP
Volume control	Digital
Headphone outputs	1
Ethernet LAN (RJ-45) ports	2
Number of handles included	1 pc(s)
AC adapter output voltage	48 V
Storage temperature (T-T)	-10 - 60 °C
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Certification	FCC

Weight and Dimensions

Depth	152.4 mm
Width	266.7 mm
Height	203.2 mm
Weight	1600 g