North American Network Operators Group|
Date Prev | Date Next |
Date Index |
Thread Index |
Author Index |
Re: Your class 'B' address space
- From: Austin Schutz
- Date: Tue Sep 29 07:25:29 1998
On Mon, Sep 28, 1998 at 05:11:42PM -0700, David R. Conrad wrote:
>> If the reason for filtering small block of space is to keep small
>>companies not generating a lot of traffic from polluting routing space I
>>don't think this applies.
>Traffic generation has absolutely no relation to prefix length filtering.
Yes, but the question is should it? If a content provider generates
a monstrous amount of traffic should they be forced to buy transit just
because the traffic is generated by a small number of hosts?
>The reason the filters are in place is because there are very few tools
>available to limit the growth of routing tables and filtering based on
>prefix length is a simple to implement unilateral mechanism that
>(theoretically) encourages people to think about their actions prior to
>flooding the routing system with long prefixes.
Ok, but in this situation 'think about' = 'forbid'. In the vast
majority of conditions it may make more sense for the organization to be
dual homed with respect to a single NSP. On the other hand perhaps the current
system encourages waste of address space by forcing organizations to claim at
least a /21 of space if they wish to be given routable space by ARIN.
What _should_ make space routable? Just network size? What about
situations where a medium size dialup ISP wants to be multihomed? Perhaps
they could theoretically use NAT to handle their dialup rather than
have a pool of ip addresses but are encouraged not to because they don't
want to jeapordize their eligibility for routable space. The same example
could be used for web hosting companies who give each virtual server an ip
How about some of the many universities with a gargantuan amount of
space used mostly for dorm rooms? Couldn't they use NAT and free up space?
Would they want to given a smaller amount of space may not be routable?
It just seems like it is more reasonable to give a company like
realaudio with a legitimate traffic generating resource the ability to
multihome than penalize them for not wasting space.
I'm not advocating a return to the bad old days where everyone and
their brother gets a class C, rather suggesting that the current system
of preventing a route explosion may have unwanted side effects.
> I'd strongly recommend reviewing the old
>CIDRD archives (wherever they might be).
I'll look for them.