Routing Order of Operations

The original information was taken from Cisco article on NAT Order of Operations. However, this order helps understand other features, like WCCP.

1. If IPSec then check input access list

2. decryption – for CET (Cisco Encryption Technology) or IPSec

3. check input access list

4. check URPF (Unicast Reverse Path Forwarding)

5. check input rate limits

6. input accounting – update stats

7. redirect to web cache

8. If configured with ip nat outside: NAT outside to inside (global to local translation)

9. policy routing

10. routing

11. If configured with ip nat outside: NAT inside to outside (local to global translation)

12. crypto (check map and mark for encryption)

13. check output access list

14. inspect (Context-based Access Control (CBAC))

15. TCP intercept

16. encryption

17. Queueing