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Re: how to test Ethernet connection



John Stumbles wrote:
Mike McCarty wrote:

    Switch
        Disadvantages:    Not secure.
                Cannot act as a bridge.


What do you mean "Cannot act as a bridge"?
When I was a network admin a switch _was_ a bridge (a multi-port one).
Is the word used differently now?

A switch uses MAC addresses for ascertaining where to forward
a message. It is unaware of IP addresses, so it cannot connect
different nets.

To put it another way, switches work at OSI Level 2, while
routers work at OSI Level 3.

And what do you mean by 'not secure'?

No firewall. Any message sent to a given MAC is delivered to
it. There is no concept of LAN side vs WAN side.

[snip]

Again, not all routers can necessarily do NAT (used to be quite the exception, though it certainly seems common enough with the cheap routers available for home use since they're usually used to access a broadband link with only one 'real' IP address.

A router *can* do NAT, but I do not mean that a router *must* do
NAT. A switch *cannot* do NAT, because it does not use IP addresss.
I'm talking about what is inherently doable, not what all routers
can do.

Mike
--
p="p=%c%s%c;main(){printf(p,34,p,34);}";main(){printf(p,34,p,34);}
This message made from 100% recycled bits.
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I can explain it for you, but I can't understand it for you.
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