Transition of ENSS206 (CERN) <-> CNSS35 (ANS N.Y.) to Ebone Service

Fri Jul 2 06:31:10 UTC 1993

Transition of ENSS206 (CERN) <-> CNSS35 (ANS N.Y.) to Ebone Service
---------------------------------------------------------------------

There will be a configuration change in the policy routing database
this Friday morning 7/2 that may affect networks using AS path
filters.

In conjunction with the rehoming of the U.S. end of the ANSnet AS 690
T1 circuit from Geneva<->New York to Geneva<->Washington, the routers
connecting this circuit will be configured to logically separate them
from the ANSnet backbone.  In particular, the two routers involved
will be reconfigured into a separate AS (1133).  The European router
(called cern-ebs2) will peer directly with the Ebone router at CERN
rather than through a 3rd party proxy as is done now.  The U.S. router
(called RS6K-US) will eventually peer directly with several neighbors
across MAE-East, although this will be minimal as part of the initial
configuraiton on Friday 7/2.

The initial step in this reconfiguration is designed to minimize the
changes to the current routing situation, however it will result in
several globally-visible changes which may effect those networks that
do AS path filtering.  In particular, routes currently advertised from
the ANSnet/NSFNET service with an AS path starting with

	690 513 1755 ...

will, after the change, be advertised with an AS path starting with

	690 1133 1755 ...

Routes now received by the ANSnet/NSFNET service from ASes 513, 559
and 590 will, after the change, have AS 1133 inserted in front, i.e.
paths currently starting with

	690 513 ...
	690 559 ...
	690 590 ...

will, after the change, be advertised as

	690 1133 513 ...
	690 1133 559 ...
	690 1133 590 ...

The ANSnet core router in Washington will be the primary gateway for
the Ebone service.  In case of a problem with this  router  RS6K-US
will use ENSS136 located at College Park, via its MAE-East connection,
as the secondary path to ANSnet/NSFNET.  However, in order to accomadate
the requirements of the current routing software on the ANSnet backbone,
RS6K-US will use a different AS number (AS 1674) in its peer session
with ENSS136.  This implies that AS 1133 will be replaced by AS 1674 
in case of problems with the primary ANSnet/NSFNET gateway to Europe.

*******************************************************************

    AS86        AS2149      AS701            AS701        AS183
   +---------+  +----+  +------------+  +-------------+  +------+
   |wtn2-mae-|  |psi-|  |Washington. |  |College.Park.|  |merit-|
   | east-ce |  |nsf |  |DC.Alter.Net|  |MD.Alter.Net |  |  rs  |
   +---------+  +----+  +------------+  +-------------+  +------+
        |.6      |.246        |.248            |.249       |.230
        |        |            |                |           |
  |-----------------MAE-East--192.41.177------------------------------|
    |        |          |           |        |       |           |
    |.220    |.253      |.245       |.247    |.240   |.241       |.242
  +-----+   +----+  +--------+  +--------+  +----+  +----+  +----------+
  |RS/US|   |E136|  |mae-east|  |mae-bone|  |icm-|  |icm-|  |Europe-RS1|
  +-----+   +----+  |  (PSI) |  |  (PSI) |  |dc1 |  |dc2 |  |  (RIPE)  |
   |.1|.2    AS690  +--------+  +--------+  +----+  +----+  +----------+
   |   ---           AS 174                    AS 1800         AS1879
   |      |    				              
   |      |                                            
   |      |                                                
   |   ----------- 192.77.156
 AS|          |  .1
1133         +---+    
   |CE BB    |C57| Washington    
   |         +---+    
   |         AS690    
   | 192.77.157
   |            
   | .2          
  +-----+
  |     | cern-ebs2
  +-----+
   |.204
   | 
   |
|-----------------CERN Ethernet--192.65.185------------------------------|
     |                 |          |         |         |         |       |
     |.4               |.130      |.202     |.201     |.1       |.2     |.3
  +-----+           +-----+    +-----+   +-----+    +-----+  +-----+  +-----+
  |AS   |           |     |    |     |   |     |    |     |  |     |  |     |
  |1755 |           |AS559|    |AS590|   |AS590|    |AS513|  |AS513|  |AS513|
  +-----+           +-----+    +-----+   +-----+    +-----+  +-----+  +-----+
  EBONE             SWITCH     EASINET   EASINET    EASINET  EASINET  EASINET
 CERN EBS          

Serpil Bayraktar/ANS
Mark Knopper/Merit