Ericsson Radio Systems AB PKRC1311004-1 Manual De Usuario
Encryption
26
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.
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:
implemented:
•
No encryption — GSM encryption algorithm version 1 (A5/1).
•
No encryption — GSM encryption algorithm version 2 (A5/2).
26.1
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.
please refer to the table of contents to find the appropriate chapter.
26.2
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.
provided in the "CHANNEL_ACTIVATION" message.
Element "Encryption Information" is optional when the Channel
Activation types are:
Activation types are:
•
Normal Assign
•
Asynchronous Handover
•
Synchronous Handover
•
Multislot Configuration
Element "Encryption Information" is not supported for Channel
Activation type "Immediate Assign".
Activation type "Immediate Assign".
Access burst, which is received from MS at handover access, is not
deciphered.
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
R1A
2001-06-26
229 (421)
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