Security Property 3:Integrity Integrity -Protect system/data from being modified. -System integrity Prevent modification to system e.g.,communication system:message modification,insertion,deletion,and replay (integrity of communication channels) -Data integrity Prevent modification to data e.g.,communication system:message modification -Mechanisms: ●Message Digest 6
6 Security Property 3: Integrity Integrity ─ Protect system/data from being modified. ─ System integrity ● Prevent modification to system – e.g., communication system: message modification, insertion, deletion, and replay (integrity of communication channels) ─ Data integrity ● Prevent modification to data – e.g., communication system: message modification ─ Mechanisms: ● Message Digest
Security Property 4:Non-repudiation Non-repudiation -Prevent someone from denying their action. .E.g.,creating a message. -Mechanisms: ●Message Digest 7
7 Security Property 4: Non-repudiation Non-repudiation ─ Prevent someone from denying their action. ● E.g., creating a message. ─ Mechanisms: ● Message Digest
Security Property 5:Authorization Authorization -Give someone permission to do something(such as access a resource) and enforce that they don't do anything beyond their permission -Mechanisms: ●Access Control 8
8 Security Property 5: Authorization Authorization ─ Give someone permission to do something (such as access a resource) and enforce that they don’t do anything beyond their permission ─ Mechanisms: ● Access Control
Security Property 6:Freshness Freshness -Verify that message is recent,is not replayed -e.g.,a check becomes invalid if not cashed within 6 months The expired check still has integrity,but not freshness -Mechanisms ●Nonce ●Expiration time 9
9 Security Property 6: Freshness Freshness ─ Verify that message is recent, is not replayed ─ e.g., a check becomes invalid if not cashed within 6 months ● The expired check still has integrity, but not freshness. ─ Mechanisms ● Nonce ● Expiration time
Security Property 7:Availability Availability: -Keep service available to legitimate users -Deny of Service attacks 10
10 Security Property 7: Availability Availability: ─ Keep service available to legitimate users ─ Deny of Service attacks