Path: utzoo!utgpu!water!watmath!clyde!rutgers!mit-eddie!uw-beaver!cornell!rochester!bbn!uwmcsd1!ig!agate!ucbvax!MONK.PROTEON.COM!mac
From: mac@MONK.PROTEON.COM (Michael A. Curtis)
Newsgroups: comp.sys.proteon
Subject: Split Horizon vs. Static Routes
Message-ID: <8802091626.AA04046@monk.proteon.com>
Date: 9 Feb 88 16:26:07 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 57


Gentlemen,

	I have been asked to take a minute to clarify the issue with
the Split Horizon and Static Routes.

	What I know:

	1) Static Routes are subject to Split Horizon/Poison Reverse.

	2) oddgw and the P4200 do not share a common Routing Protocol.

	3) The P4200 does not advertise on the ethernet that it knows
how to get to oddnet.


	My thoughts:

	1) Trick the P4200 into routing to oddnet at the expense of an
extra hop.

	2) Add a second IP address on both the oddgw and the P4200 and
change the static route in the P4200 to reflect the new IP address at
the route to oddnet.


	What happens:

	1) The P4200 will NOT advertise a route out the new IP address
to oddnet.

	2) The P4200 WILL advertise a route to oddnet via the original
IP address.

	3) Hosts on the ethernet will think the P4200 is the route to
oddnet with the expense of an extra hop, when oddgw actually is the
right route.

	4) The P4200 will NOT issue an ICMP Redirect even though it is
sending packets destined for oddnet out the same interface they were
received on because it is sending them out on another IP address on
that interface.

	5) The P4200 WILL advertise out to the backbone the correct
route to oddnet and will not incur an extra hop for traffic generated
on networks/subnets other than the ethernet.


	Hope this helps.  I'm game if anyone has any better ideas or
comments.


Best regards,


Michael A. Curtis
Proteon, Inc.