the Internet Backbone
curtis at ans.net
Tue Apr 9 03:49:16 UTC 1996
In message <[email protected][126.96.36.199]>, Howard C. Berkowitz writes:
> Here are my first thoughts on a tiered model, with attributes of each tier.
> Top level (Tier 1):
> -- provide transit as their principal business
principal IP business (some people provide voice services or do other
> -- have at least some default-free routers
Span at least one continent with default-free routers. Are able to
provide customers with default free routing as an option.
> -- have connectivity at >1 geographically separated major exchange
Yes. And span these with default free routers (ie: taking full
routing at two routers and defaulting in the middle doesn't count).
> -- need special measures to deal with BGP scaling issues inside
> their AS (or multiple AS) such as confederations, clusters, etc.
or multiple AS to deal with scaling... but if a really hefty router
comes along or we ever are able inject AS paths into the IGP, this no
How about connection speed? At least a DS3 backbone? A redundant
backbone (no single circuit failure can partition the provider)?
Can we squeeze in 1.5:
-- provide transit as their principal business
-- have at least some default-free routers
-- have connectivity at >1 geographically separated major exchange
-- do not have a default free backbone
-- maybe cannot provide full routing to all but a few customers
-- maybe not redundant DS3s
Nobody in particular in mind here.
> 2nd Level
> -- provide transit within a geographic area
> -- may have default-free routers
> -- limit operations to a geographic area; may connect to multiple
> exchanges within that area
Connection speed? Is Nearnet (mostly New England) circa 1994
equivalent to some small provider with two T1s and a bunch of routers
in a limited geographic region? Again, having an providing full
routing is a big factor too.
> 3rd Level
> -- do not provide commercial transit services, although
> they may incidentally provide transit among their customers
> -- do not do BGP peering with any "downstream" organizations.
> Their user base is part of their AS.
> -- May peer with multiple upstream providers
> 4th Level
> -- do not run BGP
> -- Internet access through provider only
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