User`s guide

Overview of IP Unicast Routing
8-2
Router Interfaces
The routing software and hardware routes IP traffic between router
interfaces. A router interface is simply a VLAN that has an IP address
assigned to it.
As you create VLANs with IP addresses belonging to different IP
subnets, you can also choose to route between the VLANs. Both the
VLAN switching and IP routing function occur within the switch.
Note
Each IP address and mask assigned to a VLAN must represent a
unique IP subnet. You cannot configure the same IP subnet on
different VLANs.
In Figure 8-1, a sGigabit witch is depicted with two VLANs defined;
Finance
and
Personnel
. Ports 1 and 3 are assigned to
Finance
; ports on
2 and 4 are assigned to
Personnel
.
Finance
belongs to the IP network
192.207.35.0; the router interface for
Finance
is assigned the IP
address 192.206.35.1.
Personnel
belongs to the IP network
192.207.36.0; its router interface is assigned IP address 192.207.36.1.
Traffic within each VLAN is switched using the Ethernet MAC
addresses. Traffic between the two VLANs is routed using the IP
addresses.
Figure 8-1
Routing Between VLANs
1
Finance Personnel
192.207.35.11
192.207.36.12 192.207.35.13 192.207.36.14
192.207.36.1192.207.35.1
234
192.207.36.0192.207.35.0