TETRA Security

Applications of different classes of keys
‣ Static Cipher Keys
– Protect all users with the same key
– Infrequent key changes
‣ ‘Dynamic’ cipher keys
– Individual Derived Cipher Key for each user
• Provides extended proof of authentication
– Common Cipher Key for groups
– Frequent key changes
‣ Group cipher keys
– Protects organisations from each other
– Frequent key changes
‣ Key management of these keys should take place from the
network
Increasing Security
Increasing Complexity
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