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
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
IXPs solve a different set of problems, namely how to interconnect with
large numbers of third party organisations with low admin overhead.
and low port count