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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Содержание 8926EM
Страница 6: ...ii ...
Страница 34: ...Getting Started ...
Страница 44: ...Introduction 1 10 1 ...
Страница 62: ...Initial Configuration 2 18 2 ...
Страница 64: ...Switch Management ...
Страница 76: ...Configuring the Switch 3 12 3 ...
Страница 118: ...Basic Management Tasks 4 42 4 ...
Страница 164: ...User Authentication 6 28 6 ...
Страница 176: ...Access Control Lists 7 12 7 ...
Страница 284: ...Quality of Service 14 8 14 ...
Страница 294: ...Multicast Filtering 15 10 15 ...
Страница 300: ...Domain Name Service 16 6 16 ...
Страница 310: ...Dynamic Host Configuration Protocol 17 10 17 ...
Страница 320: ...Configuring Router Redundancy 18 10 18 ...
Страница 344: ...IP Routing 19 24 19 ...
Страница 356: ...Unicast Routing 20 12 20 Web Click Routing Protocol RIP Statistics Figure 20 5 RIP Statistics ...
Страница 386: ...Unicast Routing 20 42 20 ...
Страница 388: ...Command Line Interface ...
Страница 400: ...Overview of the Command Line Interface 21 12 21 ...
Страница 466: ...SNMP Commands 24 16 24 ...
Страница 520: ...Access Control List Commands 26 18 26 ...
Страница 546: ...Rate Limit Commands 30 2 30 ...
Страница 612: ...VLAN Commands 34 24 34 ...
Страница 626: ...Class of Service Commands 35 14 35 ...
Страница 670: ...DHCP Commands 39 16 39 ...
Страница 716: ...IP Interface Commands 41 36 41 ...
Страница 768: ...IP Routing Commands 42 52 42 ...
Страница 770: ...Appendices ...
Страница 791: ......
Страница 792: ...20 Mason Irvine CA 92618 Phn 949 679 8000 www smc com 150200062800A R02 149100000035A R01 SMC8926EM SMC8950EM ...