RE: [NTISP] IP delegation...

Bob's Lists ( (no email) )
Fri, 3 Dec 1999 22:19:31 +0300

Pardon my ignorance on this issue, but in starting to sell DSL our company
has run into a problem delegating IP addresses to customers. Due to the
configuration constraints of the Cisco router (3810) we are using, we have
assigned a subnet mask for our end users of thus allowing all
of the users access to all of the addresses in the assigned class C.

My question is: What would be the best way to avoid customers to just grab
unused IPs for their workstations? The only way I could do it now is
assign all the untaken IP to a Nt workstation, but that is cumbersome and
quite annoying.


The only suggestion I can offer, is to get a network admin who knows what
they're doing.

First of all, is not a class C, it is 2 class C's (or 1 /23,
and they're now known). Using that mask, and if, indeed, your upstream has
allocated you a class C, I'm surprised they haven't nailed you yet for some
'unusual traffic' on your link...

Next, you should be allocating customers only what they need. If they need 1
address, give them a /30 (with the gateway on your router, leaving 1 IP at
the customer end. Similarly for customers requiring more addresses, assign
them appropriately sized subnets.

What configuration restraints?

Whoever set it up being incapable is the only restraint I see here.



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