ECS4660-28F_Management Guide-R03

Table Of Contents
C
HAPTER
18
| General IP Routing
IP Routing and Switching
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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.
Figure 442: Virtual Interfaces and Layer 3 Routing
IP ROUTING AND 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
VLAN 1
VLAN 2
Inter-subnet traffic (Layer 3 switching)
Routing
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Intra-subnet traffic (Layer 2 switching)