CIDR FAQ

Curtis Villamizar wrote:

:
> Hank Nussbacher wrote:
> >
> > >Simon Poole wrote:
> > >>
> > >> Yakov, if you have data that CIDR is -not- working for new allocations
> > >> please present it here.
> > >>
> > >> Simon
> > >
> > >CIDR doesn't work as it should. We had to inject all of the more specifics
> > >of 194.45/16 cause Sprintlink isn't able to handle CIDR routes correctly.
> >
> > Can someone explain this a bit more? This sounds like a showstopper
> > for CIDR.
> >
>
> Xlink (AS517) was announcing 194.45.0.0/16 via Ebone. There are some
> networks within this block announced by PSI. Routing table at PSI looks
> like
>
[ deleted for brevity ]
>
> But Sprintlink was routing
>
[ deleted for brevity ]
>
> TT to Sprintlink didn't help. After 4 days still no response. I've fixed
> this silly routing by announcing all more specifics.
>
> Arnold

The way this is supposed to work is the originator announces the
aggregate and registers in in the IRR. When confident that the
aggregate is reaching where it needs to go, the originator stops
announcing the components.

I think I've to clarify. AS517 is announcing 194.45.0.0/16 since a couple of
months and we did *NOT* announce any more specific. On May, 17th 1995 routing
for 194.45.0.0/16 broke the firt time. Here's what Vadim Antonov wrote:

   Message-Id: <199505172313.TAA10358@titan.sprintlink.net>
       noc@mci.net, noc@xlink.net
   Status: RO
   
   That's funny:
   
   ICM-MAE-E>sh ip bgp 194.45.0.0 255.255.0.0 s
   BGP table version is 4081305, local router ID is 198.67.131.49
   Status codes: s suppressed, * valid, > best, i - internal
   Origin codes: i - IGP, e - EGP, ? - incomplete
   
      Network Next Hop Metric LocPrf Weight Path
   *> 194.45.0.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *>i194.45.0.0/16 192.157.65.49 0 100 0 1755 517 ?
   *> 194.45.1.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.2.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.3.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.4.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.5.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.6.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   *> 194.45.7.0 192.41.177.245 90 0 1239 174 i
   * i 192.157.65.25 90 0 1239 174 i
   ICM-MAE-E>
   
   Routing appears to be ok on our side, so i included MCI in the list.
   
   --vadim
   
   From nipper@xlink.net Wed May 17 16:22:13 1995
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