| Inside the Portswitch modules, there are separate groups of wires
associated with each of the the networks to which the Portswitch can
attach its ports.
We build ASICs (special chips) to perform the switching function
between the front panel ports and the networks inside the box. All the
groups of wires for all the networks are attached to each of the ASICs.
Typically, one ASIC also handles four front-panel ports. Inside the
ASIC is all the circuitry that is needed to randomly assign any of the
front panel ports to any of the networks inside the box.
The switching function itself is much like a set of electronic
multiplexers inside each of the ASICs.
Any ports attached to the same internal network act as though they are
part of their own, independent repeater.
You are correct to say that the Portswitch products are not switches in
the sense that they do not store packets and/or forward them based on
addresses. The function that is really being performed under software
control is akin to walking up to the hub, pulling a wire out of a
repeater port and putting it into a port of a repeater on a different
LAN. With the Portswitches and Hubwatch, you can do this from halfway
around the world, if you like.
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