Specifications

CHAPTER 4
InterVLAN Routing
Routing
1. Apply input ACL
2. Switch if entry is in CEF cache
3. Identify exit interface and next-hop address using routing table
4. Apply output ACL
Output
1. Apply outbound VLAN ACL.
2. Apply outbound QoS ACL.
3. Select output port.
4. Place in interface queue.
5. Rewrite source and destination MAC, IP checksum and frame check sequence, and decrement TTL (Time to Live
field in the IP header).
6. Forward.
Understanding the Switching Table
Multilayer switches use Application Specific Integrated Circuits (ASIC) to forward packets at wire speed. The Content
Addressable Memory (CAM) table, used for Layer 2 switching, is created by recording the source MAC address and
ingress port of each frame. It contains binary values (0 or 1) and must find an exact match to have a hit.
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CCNP SWITCH 642-813 Quick Reference by Denise Donohue
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