North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

RE: Route table growth and hardware to the filter

  • From: Jon Lewis
  • Date: Sat Sep 08 07:55:20 2007

On Sat, 8 Sep 2007, Lincoln Dale wrote:

what i think it boils down to is that many folks seem to run default-free
because they can, because its cool, because its what tier-1 folks do, because
(insert cool/uber reason why here), but not necessarily because they HAVE TO.

Consider a regional or local ISP providing BGP to a customer. The customer also has a connection to a "Tier 1". The customer may start asking questions when they notice they get 250k routes from one provider and only 50k to 80k less routes from you.

I suppose some "Tier 1"s got away with this in the past maybe there are acceptable answers.

even if you're a content-provider in North America and want to ensure an
"optimal path" of traffic, generally speaking, you could accept prefixes
(as-is) from ARIN allocations but for (say) APNIC and RIPE do either some
degree of filtering or just push it via a default.

I actually suggested this yesterday to a friend who runs an ISP and has just run into his 7500s running out of RAM and crashing when turning up a new transit provider with full BGP routes. Filtering the APNIC and RIPE regions and adding a default will very likely let him fit "mostly full routes" on his router and put off the inevitible fork-lift upgrade a while longer.

 Jon Lewis                   |  I route
 Senior Network Engineer     |  therefore you are
 Atlantic Net                |
_________ for PGP public key_________