What is network security? Confidentiality:only sender,intended receiver should "understand"message contents o sender encrypts message o receiver decrypts message Authentication:sender,receiver want to confirm identity of each other Message Integrity:sender,receiver want to ensure message not altered (in transit,or afterwards) without detection Access and Availability:services must be accessible and available to users 8:Network Security 8-48: Network Security 8-4 What is network security? Confidentiality: only sender, intended receiver should “understand” message contents  sender encrypts message  receiver decrypts message Authentication: sender, receiver want to confirm identity of each other Message Integrity: sender, receiver want to ensure message not altered (in transit, or afterwards) without detection Access and Availability: services must be accessible and available to users