Cisco 7970G Administration Guide - Page 43

Chapter 1 An Overview of the Cisco Unified IP Phone Understanding Security Features for Cisco Unified IP Phones - Disabled-If the switch does not support multi-domain authentication, disable the Voice VLAN and consider assigning the port to the native VLAN. See the "Security Configuration Menu" section on page 4-38 for more information. • Enter MD5 Shared Secret-If you disable 802.1X authentication or perform a factory reset on the phone, the previously configured MD5 shared secret is deleted. See the "802.1X Authentication and Status" section on page 4-51 for more information. Security Restrictions A user cannot barge into an encrypted call if the phone that is used to barge is not configured for encryption. When barge fails in this case, a reorder tone (fast busy tone) plays on the phone on which the user initiated the barge. If the initiator phone is configured for encryption, the barge initiator can barge into an authenticated or nonsecure call from the encrypted phone. After the barge occurs, Cisco Unified Communications Manager classifies the call as nonsecure. If the initiator phone is configured for encryption, the barge initiator can barge into an encrypted call, and the phone indicates that the call is encrypted. A user can barge into an authenticated call, even if the phone that is used to barge is nonsecure. The authentication icon continues to appear on the authenticated devices in the call, even if the initiator phone does not support security. Cisco Unified IP Phone 7970G/7971G-GE Administration Guide for Cisco Unified Communications Manager 6.1 OL-14626-01 1-25