Describing Routing Between VLANs参考.ppt

Implementing Inter-VLAN Routing Describing Routing Between VLANs Inter-VLAN Routing with External Router Inter-VLAN Routing External Router Configuration Commands Configure on subinterface encapsulation dot1Q (or isl) 10 ip address 10.10.1.1 255.255.255.0 Verify show vlan 10 show ip route Inter-VLAN Routing on External Router: 802.1Q Trunk Link Inter-VLAN Routing on External Router: ISL Trunk Link Verifying Inter-VLAN Routing Verifying the Inter-VLAN Routing Configuration Explaining Multilayer Switching Layer 2 Switch Forwarding Process Logical Packet Flow for a Multilayer Switch IP Unicast Frame and Packet Rewrite CAM Table Requires an exact match on all bits Matching is a binary operation: 0 or 1 Provides very high-speed lookups TCAM Table Matches only significant values Matches based on three values: 0, 1, or X (either) Masks used to wildcard some content fields Summary A router on a stick can be used to route between VLANs using either ISL or 802.1Q as the trunking protocol. A router on a stick requires subinterfaces, one for each VLAN. Verify inter-VLAN routing by generating IP packets between two subnets. Multilayer switches can forward traffic at both Layer 2 and Layer 3. Multilayer switches rewrite the Layer 2 and Layer 3 header using tables held in hardware. Cisco Network Academy. All rights reserved.. CCNP+ BSMSN v3.0 Cisco Network Academy. All rights reserved.. CCNP+ BSMSN v3.0 Single trunk link carries traffic for multiple VLANs to and from router. The ping command tests connectivity to remote hosts. Router#show ip interface brief Displays the current IP configuration per VLAN Router#show ip route Displays IP route ta