Routing Path Management; Routing Protocols - SMC Networks SMC6724L3 Management Manual

C
ONFIGURING THE
there, the switch broadcasts an ARP packet to all the ports on the
destination VLAN to find out the destination MAC address. After the
MAC address is discovered, the packet is reformatted and sent out to the
destination. The reformat process includes decreasing the Time-To-Live
(TTL) field of the IP header, recalculating the IP header checksum, and
replacing the destination MAC address with either the MAC address of the
destination node or that of the next hop router.
When another packet destined to the same node arrives, the destination
MAC can be retrieved directly from the Layer 3 address table; the packet is
then reformatted and sent out the destination port. IP switching can be
done at wire-speed when the destination address entry is already in the
Layer 3 address table.
If the switch determines that a frame must be routed, the route is
calculated only during setup. Once the route has been determined, all
packets in the current flow are simply switched or forwarded across the
chosen path. This takes advantage of the high throughput and low latency
of switching by enabling the traffic to bypass the routing engine once the
path calculation has been performed.

Routing Path Management

Routing Path Management involves the determination and updating of all
the routing information required for packet forwarding, including:
• Handling routing protocols
• Updating the routing table
• Updating the Layer 3 switching database

Routing Protocols

The switch supports both static and dynamic routing.
• Static routing requires routing information to be stored in the switch
either manually or when a connection is set up by an application outside
the switch.
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WITCH