Where to buy Internet IP addresses

Jack Bates jbates at brightok.net
Tue May 5 14:11:23 CDT 2009

Joe Greco wrote:
> Now, the question is, if you're sending all these prefix requests up to
> the ISP's router, why is *that* device able to cope with it, and why is
> the CPE device *not* able to cope with it?
The CPE cannot cope with it due to lack of a chaining standard and the 
lack of customer understanding of configuring a router. An ISP, as 
currently designed will manually assign prefix lengths and how they are 
handed out at each layer of the network. A home user should not be 
expected to understand this level of complexity. A CPE would have to be 
told HOW to divide it's variably received prefix to assign it's own 
networks and then issue prefixes to other routers behind it.

What is missing, unless I've missed a protocol (which is always 
possible), is an automated way for a CPE to assign it's networks, pass 
other networks out to downstream routers in an on-need basis. I say 
on-need, as there may be 3 routers directly behind the CPE and each of 
those may get additional routers and so on and so forth. A presumption 
could be made that route efficiency is not necessary at this level. ie, 
would it be practical or expected that an automatically configured 
network support > 100 routes or whatever a CPE can normally handle?

Of course, if this support is built at a CPE level, there's no reason 
the protocol can't be extended and supported at the ISP level as well 
for those who wish to utilize it. An ISP, would of course prefer prefix 
aggregation and controls to set minimum and maximum aggregate space for 
a customer.

> You have an ISP network, with a large amount of space available, and a
> lesser amount of space dedicated to the POP.

This setup in the ISP network is handled by hopefully clueful engineers 
and probably not automatically assigned by some cool protocol that 
routers speak (which would be cool, though, even if impractical).

> So what we want is something that can intelligently handle delegation
> in an automatic fashion, which probably includes configurable settings
> to request/register delegations upstream, and to accept/manage them
> downstream.  There's no reason that this shouldn't be basic router
> capabilities.

For the home router, I believe that this is mandatory if we wish to 
continue to allow self configuring networks for home users. A little 
extended logic and it can also be useful in larger networks, possibly 
even to the point of an enterprise network able to completely number 
itself (including renumbering itself as necessary).


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