Elastic Networks BitStorm L3S-T, Руководство пользователя

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Routing
This Layer Three Gigabit Ethernet Switch is both a switch and a router.
It operates at Layer 2 like traditional switches, forwarding and discarding packets based only on Media Access
Control layer (MAC) addresses. Like traditional routers, it also operates at Layer 3, using network layer
information to route packets to another router, switched network segment or end-station.
Wire-speed routing
But, unlike traditional routers, the Switch routes at wire-speed, nearly ten times faster than conventional routers.
Conventional routers maintain routing tables in software and use a CPU to look up and maintain these
addresses. This Switch achieves routing at wire speed by using Application Specific Integrated Circuits, or
ASICs, to maintain routing tables in hardware.
The
Switch eliminates the need for routers in the local area network (LAN). It might also be called a high-speed
or hardware-based router.
Migrating from routing to multi-layer switching
Migrating from a router-centric network to a BitStorm L3S network is extremely simple.
A typical, traditional collapsed backbone layout in a small company places the router in the center of the network
to create IP subnets and stop broadcast traffic from flooding the entire network.
That router can be replaced by a BitStorm L3S Layer 3 Gigabit Ethernet switch and moved to the edge of the
LAN to handle WAN communications.
Layer 2 switches can now be moved into workgroups, replacing hubs and putting each user on a dedicated port.
As traffic demands increase, those Layer 2 switches can be replaced by more
BitStorm L3S
switches.
How the Switch handle IP routing
On a local network, a Layer 2 switch identifies and transfers packets by reading the hardware addresses—the
source and destination MAC addresses. A Layer 2 switch cannot forward traffic destined outside of its local
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