Ericsson Radio Systems AB PKRC1311004-1 Manual De Usuario
Encryption
P003010A
MS
BTS
BSC
Ciph Mode CMD
Ciph Mode Com
Encryption CMD
DI (Ciph Mode Com)
RR (SDCCH)
RR (SDCCH)
Figure 95
26.4
Encryption Mode Change at Mode Modify
Purpose
This function is used to change the encryption mode (key and
algorithm) on an active dedicated channel group.
algorithm) on an active dedicated channel group.
Preconditions and initiation
Encryption is either activated or deactivated.
The function is initiated when the RBS receives a
MODE_MODIFY_COMMAD message from BSC.
MODE_MODIFY_COMMAD message from BSC.
Description
The message (MODE_MODIFY_COMMAD) contains the new key and
algorithm to use. The ciphering key and algorithm identifier can be
changed to any valid value.
algorithm to use. The ciphering key and algorithm identifier can be
changed to any valid value.
If "Algorithm Identifier" is "No encryption shall be used", the RBS
updates the key by clearing the stored key and ciphering is stopped /
GSM 04.08:3.4.7/.
updates the key by clearing the stored key and ciphering is stopped /
GSM 04.08:3.4.7/.
EN/LZT 720 0008
R1A
2001-06-26
231 (421)
© Ericsson Radio Systems AB
— All Rights Reserved —