CHAPTER 2 | Ne twork Planning
Application Examples
USING LAYER 3
R
OUTING
VLANs can significantly enhance network perfo rmance and security. However , if
you use conventional routers to interconn ect VLANs, you can lose most of your
performance advantage. These Gigabit Ethernet Switches are routing switches
that provide wire-speed routing, which allows you to eliminate your conventional
IP routers, except for a router to handle non-IP protocols and a gateway router
linked to the WAN. Just assign an IP address to any VLANs that need to
communicate. The switches will continue to se gregate Layer 2 traffic based on
VLANs, but will now provide inter-VLAN connections for IP applications. The
switches will perform IP routing for specified VL AN groups, a directly connected
subnetwork, a remote IP subnetwork or host address, a subnetwork broadcast
address, or an IP multicast address.
Figure 11: IP Routing for Unicast Traffi
R&D
Test ing IP Network 1
IP Network 2
VLAN 1
VLAN
2
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