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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: selective auto-aggregation
Only 1 question: What about the companies that have a /24 out of the /20 0r /21 that are multi-homed? If the route rules are not carefully prepared the multi-homed customer then might be single-homed and tied to the upstream they got the IP's from. Thoughts? Jim >-----Original Message----- >From: [email protected] [mailto:[email protected]] >Sent: Thursday, April 17, 2003 3:56 PM >To: [email protected] >Subject: selective auto-aggregation > > > >I believe we're losing the aggregation war. More and more entities are >deaggregating, and not announcing their largest aggregates which makes >prefix-length filtering less effective. > >I'ld like to propose the concept of selective aggregation, whereby >a router can be configured to aggregate based upon rules. > >For example, if an RIR allocation boundary for a particular /8 is >/21, that routes which are longer than /21 could be aggregated to >/21 rather than discarded. Obviously, this would only be effective >facing one's transit, since aggregating a peer would violate most >peering agreements. In transit-free networks, this functionality would >not be useful. > >Similarly, the ability to auto-aggregate contiguous networks originated >by the same AS, which could be applied even to routes with lengths >shorter than an RIR boundary. This functionality could be useful >facing ones peers. > >This type of thing would need to be selective, since permitted >deaggregation (no-export tagged routes with meaningful MEDs) can >still be useful between entities which agree to such things. > >If we can, I'ld like to avoid a holy war on whether deaggregating >is someone's god given right, and stick to the premise that there >are networks who will enforce aggregation policies, and want to do so >in the most effective manner possible. > >
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