Enabling Ciphering

Ciphering is a mechanism to ensure the subscriber's privacy on the radio path by confidentially transmitting both user information and associated signaling data. To this end, the data transmitted via the radio path is not the proper user data, but a binary combination of this user data and a ciphering bit stream. Ciphering is achieved by performing an operation between a variable pseudo-random sequence and the useful data.

Encrypted voice and data communications between the MS and the network is accomplished through use of the ciphering algorithm A5. Encrypted communication is initiated by a ciphering mode request command from the GSM network. Upon receipt of this command, the mobile station begins encryption and decryption of data using the ciphering algorithm (A5) and the ciphering key (Kc).

1.Go to EMS >Configuration >NSS >VLR.

2.Click the button at the upper right corner.

1.On the System tab, configure the relevant parameters given in the following table.

2.Click the button to update parameters to application servers.

Sub-parameter	Description (Click highlight SAVE after change)	Recommended Value
Ciphering	Enabling this parameter forces the mobile to use ciphering over the air interface.	Enable
Ciphering Algorithm	Select a ciphering algorithm from the drop-down menu. These algorithms encrypt voice between the mobile station and the base station.	A5_1