NSFNET T1 backbone routing configuration changes

skw skw
Fri Jun 5 05:59:55 UTC 1992

Hi.  The T1 backbone routing software allows up to 1200 routes to
be configured at any metric per NSS.  We reached this limit a while 
back at several sites.  With the May 12 update, we made the  
following adjustments to the T1 backbone routing database in order 
to stay within the 1200 route per unique metric per NSS limit and 
to provide future space:
NSS 8     moved 745 nets with AS 756 (T1-T3 Network Interconnect 
          (Princeton, NJ) metric 11 to metric 17.

NSS 9     moved 558 nets with AS 184 (Milnet (FIX-East)) metric 1 & 2,
          to AS 184 metric 7 & 8.

NSS 10    moved 208 nets with AS 590 (EASInet Regional Network) metric 1 
          to metric 7.

NSS 13    moved 558 nets with AS 164 (Milnet (FIX-West)) metric 1 & 2,
          to AS 164 metric 7 & 8.

NSS 17    moved 745 nets with AS 750 (T1-T3 Network Interconnect 
          (Ann Arbor, MI)) metric 10 to metric 16.
While these changes are transparent to backbone routing, it was 
brought to our attention that they may affect sites which use the
nis.nsf.net reports to generate access lists, etc.  So, we will 
keep this list informed as these reconfigurations become necessary 
in the future.
Also, metric 7 is only being used as a first priority metric in the T1 
backbone routing database as of today's routing config update.

  --Steve Widmayer

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