13.2 Expiration Model

• 13.2.1 Server-Specified Expiration
• 13.2.2 Heuristic Expiration
• 13.2.3 Age Calculations
• 13.2.4 Expiration Calculations
• 13.2.5 Disambiguating Expiration Values
• 13.2.6 Disambiguating Multiple Responses