SMC Networks 8926EM, Installation Manual

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2-6
Network Planning
2
Using Layer 3 Routing
VLANs can significantly enhance network performance and security. However, if you
use conventional routers to interconnect 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 segregate Layer 2 traffic based on VLANs, but will now
provide inter-VLAN connections for IP applications. The switches will perform IP
routing for specified VLAN groups, a directly connected subnetwork, a remote IP
subnetwork or host address, a subnetwork broadcast address, or an IP multicast
address.
Figure 2-5 IP Routing for Unicast Traffic
IP Network 1
R&D
VLAN 1
VLAN 2
Testing
IP Network 2