斗 长 Secure communication ￥斗 ★★ o Confidentiali Attacker should not be able to understand data ≈ Authentication: Assure receiver that message is from the right sender s Freshness. Attacker should not be able to replay an old request o Availability No denial-of-service10 Secure Communication  Confidentiality: – Attacker should not be able to understand data  Authentication: – Assure receiver that message is from the right sender  Freshness: – Attacker should not be able to replay an old request  Availability: – No denial-of-service