AS690 advisory update

Elise Gerich epg at
Mon Nov 13 16:47:07 UTC 1995


>Steve Heimlich writes:
> Folks,
> As previously mentioned, ANS is moving to a new configuration system
> which will eliminate the need for registering AS690 advisories with
> RIPE-181 route objects.  Our initial deployment described below
> has gone well, and as a result we will freeze our aut-num (currently
> still machine generated based on advisories) on Friday, 11/17, at
> midnight ET (Saturday, 11/18, 5am GMT).  Tuesday morning's AS690
> config run will use the frozen aut-num.
> After this time, AS690 advisories will be ignored.  Policy toward
> routes registered in the IRR will be based solely on origin AS.
> The origin AS will be expanded to the set of route objects registered
> for that origin AS; the resulting list of prefixes will be used in
> generating router configurations, as today.
> Refinement of AS690 import policies will begin on a per AS basis
> next week, starting with large origin ASes.  The human readable
> version of the 18,000 line AS690 aut-num is currently available
> at:
> Steve
> --------
> To: nanog at
> Subject: AS690 policy configuration changes
> Date: Mon, 06 Nov 1995 18:43:22 -0500
> From: Steve Heimlich <heimlich at>
> All,
> Starting with Friday [11/10] morning's config run, AS690 will pick
> up any route listed in various routing registries, including both
> those routes with advisories and those routes without advisories.
> ANS customers will not be affected by this change.
> Routes without advisories will be examined for origin AS and will
> inherit the most popular policy currently used for that AS.  For
> example, if a route for 147.225/16 (origin AS1660) were listed
> without an advisory, we would configure ourselves to listen for
> 147.225/16 in the same way that we listen to most other AS1660
> routes (only from AS 1324 in this case).
> If a route is registered in an AS for which we don't have existing
> policy, it will not be routed.  In the example above, if 147.225/16
> were registered without an aggregate, and it were the only route
> registered with origin 1660, then we will not route it.  We have
> a tool which flags such new ASes, and policy toward them will be
> created regularly.  The rate of growth in number of ASes is not
> high, particularly relative to the rate of growth in number of
> routes.
> For now, we will continue to build our policy dynamically from the
> advisory attributes.  Assuming that this hybrid deployment goes
> well, we intend to freeze our policy and convert to a system which
> ignores advisories altogether.  With this system, the mechanics of
> shifting policy will be quite easy (essentially involving only
> ANS).  I expect to announce that freeze and shift in the next week
> or so.  At that point, those folks who want to strip AS690 advisories
> from any database may do so without a problem; as mentioned above,
> any advisories registered after that time will be ignored.
> Steve

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