IP Routing
19-2
19
Each VLAN represents a virtual interface to Layer 3. You just need to provide the
network address for each virtual interface, and the traffic between different
subnetworks will be routed by Layer 3 switching.
IP Switching
IP Switching (or packet forwarding) encompasses tasks required to forward packets
for both Layer 2 and Layer 3, as well as traditional routing. These functions include:
• Layer 2 forwarding (switching) based on the Layer 2 destination MAC address
• Layer 3 forwarding (routing):
- Based on the Layer 3 destination address
- Replacing destination/source MAC addresses for each hop
- Incrementing the hop count
- Decrementing the time-to-live
- Verifying and recalculating the Layer 3 checksum
If the destination node is on the same subnetwork as the source network, then the
packet can be transmitted directly without the help of a router. However, if the MAC
address is not yet known to the switch, an Address Resolution Protocol (ARP)
packet with the destination IP address is broadcast to get the destination MAC
address from the destination node. The IP packet can then be sent directly with the
destination MAC address.
If the destination belongs to a different subnet on this switch, the packet can be
routed directly to the destination node. However, if the packet belongs to a subnet
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Summary of Contents for 8926EM
Page 6: ...ii ...
Page 34: ...Getting Started ...
Page 44: ...Introduction 1 10 1 ...
Page 62: ...Initial Configuration 2 18 2 ...
Page 64: ...Switch Management ...
Page 76: ...Configuring the Switch 3 12 3 ...
Page 118: ...Basic Management Tasks 4 42 4 ...
Page 164: ...User Authentication 6 28 6 ...
Page 176: ...Access Control Lists 7 12 7 ...
Page 284: ...Quality of Service 14 8 14 ...
Page 294: ...Multicast Filtering 15 10 15 ...
Page 300: ...Domain Name Service 16 6 16 ...
Page 310: ...Dynamic Host Configuration Protocol 17 10 17 ...
Page 320: ...Configuring Router Redundancy 18 10 18 ...
Page 344: ...IP Routing 19 24 19 ...
Page 356: ...Unicast Routing 20 12 20 Web Click Routing Protocol RIP Statistics Figure 20 5 RIP Statistics ...
Page 386: ...Unicast Routing 20 42 20 ...
Page 388: ...Command Line Interface ...
Page 400: ...Overview of the Command Line Interface 21 12 21 ...
Page 466: ...SNMP Commands 24 16 24 ...
Page 520: ...Access Control List Commands 26 18 26 ...
Page 546: ...Rate Limit Commands 30 2 30 ...
Page 612: ...VLAN Commands 34 24 34 ...
Page 626: ...Class of Service Commands 35 14 35 ...
Page 670: ...DHCP Commands 39 16 39 ...
Page 716: ...IP Interface Commands 41 36 41 ...
Page 768: ...IP Routing Commands 42 52 42 ...
Page 770: ...Appendices ...
Page 791: ......