[KLUG Members] some network questions

[Mike Williams]

Bert Bbbink wrote:

>>Nope,  the input parameters result in an undefined result; so it should
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>not be expected to make sense, like division by zero.
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>You might not have meant it that way but the dividing by zero comparison
>makes  really sence: the situation ought not to makes sence. I like that
>explanation. Thank you.
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The comparison is a little bit suspect, because a computer is expected 
to error out and stop executing the program (gracefully, you hope) when 
it encounters a division by zero error.  "Stopping execution" is not 
exactly an ideal solution for a network device, so they're expected to 
keep going in spite of instructions that don't make any sense. 

Since a subnet mask with a zero in the middle shouldn't happen, there's 
no standard for what to do about it, so it is very likely to very 
between operating system, OS versions, and hardware.

>>But it does make sense.  RARP is defeating your subnetting by turning the
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>whole mess into a really slow LAN - that is what RARP is (or was) for,
>non-routable protocols could be bridged over WAN links.
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Think you could explain that a bit?  I ignored this discussion at first, 
thinking RARP was a routing protocol I wasn't familiar with (hey, it 
sounds a lot like RIP), but some quick googling suggests that it's an 
alternative to DHCP for diskless workstations.  How would getting a 
protocol level address (IP or similar?) from a hardware level address 
(MAC) help you go across a subnet if you're dealing with a protocol that 
doesn't know subnets?  Is this like ethernet bridging where you forward 
MAC information across the link?

>>Different compression techniques often only support given protocols or
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>have topology expectations - so they are always sort of a wild card.
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>Okee and thats why rarp gets it running while it does not make sence :-)
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>This finaly puts things in its place. Great!
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>Bert.
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