User's Manual

458 Features overview
ATTENTION
Phase I IP Phones do not support SRTP.
ATTENTION
The IP Softphone 2050 supports media security for CS 1000 Release 5.0
and later. The IP Softphone 2050 supports UNIStim key (USK) SRTP media
encryption only.
Operating parameters
The Media Security feature has the following operating parameters
•
During a firmware upgrade, the Media security is automatically
disabled.
•
Media security does not support duplicate media streams encryption,
such as IP Call Recording.
• Pre-Shared key (PSK) SRTP media encryption negotiates after the
call is setup. The first few seconds of the call can sometimes be
unsecured; after the lock icon displays the call is secure. UNIStim key
(USK) SRTP media encryption is negotiated before the call is setup
so no delays occur. In both versions of SRTP the call is secure when
the lock displays.
When USK SRTP negotiates, an outlined lock icon and Encrypted
appears on the display. When PSK SRTP negotiates, a solid lock icon
displays but Encrypted does not display.
ATTENTION
A maximum of 24 characters for a name in the Personal Directory, Callers
List, or Redial List can appear in the display area. If PSK SRTP is enabled
and the name has the maximum of 24 characters, the last character in the
name truncates to display the secure lock icon.
•
SRTP PSK does not negotiate if you use 10ms G.729, due to the
small payload size. The call remains in RTP. All other payloads are
supported for PSK SRTP. USK SRTP supports all payloads.
ATTENTION
The IP Phone 1210, IP Phone 1220, and IP Phone 1230 do not support 10ms
G.729.
Configuration
For CS 1000 Release 5.0 or later, you can configure a system-wide
configuration setting (USK SRTP), which controls whether or not the CS
1000 system is capable of providing Media Security.
Nortel Communication Server 1000
IP Phones Fundamentals
NN43001-368 02.07
5 February 2009
Copyright © 2003-2009 Nortel Networks
.