Re: The IPv6 Travesty that is Cogent's refusal to peer Hurricane Electric - and how to solve it
From: Nick Hilliard <nick@foobar.org> multihop bgp means that you don't have synchronised ethernet carrier status between the provider and customer routers. This in turn means that if there's an intermediate connectivity problem, bgp will need to time out before it notices and reroutes. During this period, traffic will be black-holed. This is a crock.
It is but nobody worries about that, we trust route servers at IX carrying way more traffic than most of these access circuits. brandon
On 25/Jan/16 21:28, Brandon Butterworth wrote:
It is but nobody worries about that, we trust route servers at IX carrying way more traffic than most of these access circuits.
Yes, but if those go belly-up, you have another exchange point to fall back to, a bi-lateral peering session, or an upstream provider. Or all three. A "critical" device falling over in my network is far worse prospect to experience. Mark.
Brandon Butterworth wrote:
It is but nobody worries about that, we trust route servers at IX carrying way more traffic than most of these access circuits.
more sessions for sure, but rarely more traffic. The issue at hand is that multihop bgp at the isp edge is relatively straightforward to fix by using big boxes, or mpls PW head-end to tunnel to a big box, or by using small-fib boxes with large RIBs and selective fib download. IXPs solve a different set of problems, namely how to interconnect with large numbers of third party organisations with low admin overhead. There aren't easy solutions here. Nick
participants (4)
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Brandon Butterworth -
Mark Tinka -
Nick Hilliard -
Randy Bush