Encryption
32
Encryption
Encryption is used for ciphering and deciphering of information to and
from an MS over a dedicated resource. The RBS supports two
encryption modes, either using no encryption or using a GSM
encryption algorithm.
The BSC controls which encryption mode is used.
There are two product variants with different encryption algorithms
implemented:
•
No encryption — GSM encryption algorithm version 1 (A5/1).
•
No encryption — GSM encryption algorithm version 2 (A5/2).
32.1
References
/GSM 04.08/
GSM 04.08 (phase 2) version 4.7.0
/GSM 08.58/
GSM 08.58 (phase 2) version 4.7.0
Whenever a reference is made to a function described in another chapter,
please refer to the table of contents to find the appropriate chapter.
32.2
Start Encryption at Channel Activation
Purpose
To initiate encryption mode on a dedicated logical channel.
Precondition and initiation
The function starts encryption if element "Encryption Information" is
provided in the "CHANNEL_ACTIVATION" message.
Element "Encryption Information" is optional when the Channel
Activation types are:
•
Normal Assign
•
Asynchronous Handover
•
Synchronous Handover
•
Multislot Configuration
Element "Encryption Information" is not supported for Channel
Activation type "Immediate Assign".
Access burst, which is received from MS at handover access, is not
deciphered.
•
Supported channel numbers: /GSM 05.02:6.4/
•
Bm + ACCH
•
Lm + ACCH
•
SDCCH/8 + ACCH
•
SDCCH/4 + ACCH (and TN=0)
EN/LZT 720 0008
P2A
2001-11-28
291 (485)
© Ericsson Radio Systems AB
— All Rights Reserved —
P
re
li
m
in
a
ry
Summary of Contents for RBS 2106
Page 2: ...P r e l i m i n a r y ...
