AS number
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Some router implementations use an AS number as a form of tagging to
identify interior as well as exterior routing processes. This tag ...
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This idea may at first seem slightly alien to some, but it high-
lights the clear distinction in the use of the AS number as a
representation of routing policy as opposed to some form of
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... network operator should
create its own AS number. In this case, the site should ensure
that it has the necessary facilities to run appropriate routing
protocols, such as BGP4.
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... create an AS before you really
need it. The AS number space is finite and the limited amount
of re-engineering needed when you connect to another service
provider should be considered as a natural step in transition.
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... * History
AS number application forms have historically made no reference
to routing policy. All too often ASes ...
... exterior routing protocols. If already running an exterior routing
protocol, it is perfectly reasonable to use your AS number as an IGP
tag ...
... tag; if you do not, choosing from the private use range is also
acceptable (see "Reserved AS Numbers"). Merely running an IGP is not
grounds for registration ...
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The AS number space is a finite amount of address space. It is
currently defined as a 16 bit ...
... 16 bit integer and hence limited to 65535
unique AS numbers. At the time of writing some 5,100 ASes have been
allocated and a little under 600 ASes ...
... Reserved AS Numbers ...
... Internet Assigned Numbers Authority (IANA) has reserved the
following block of AS numbers for private use (not to be advertised
on the global Internet ...
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AS number to owner mappings are public knowledge (in WHOIS), and
attempting to change that would serve only to confuse those people
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