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From: rls@rx7.osa.com (Rich Scott)
Newsgroups: comp.dcom.sys.cisco
Subject: Re: Routing Entry of 0.0.0.0
Message-ID: <32497@boulder.Colorado.EDU>
Date: 20 Feb 91 17:11:36 GMT
Sender: news@boulder.Colorado.EDU
Lines: 33


(I originally tried to reply directly to Kevin, but was unable to - very
 strange path (& aliases) he uses for mail)

  Kevin asks:

|I am having trouble with my network.  We have all cisco gateways, and all 
|are above software rev 8.0.  I am using NetCentral to monitor all this.  When 
|I show the routing table from NetCentral it gave the routing table with an 
|entry of Destination being 0.0.0.0
|
|This is a little wierd.  It may be a broadcast address (except it's really 
|all ones), or it could be the weather...

	Actually, 0.0.0.0 is the numeric notation for the "default" 
address - the address to send  packets that aren't matched by any other 
network routes.

	You may want to look at RFC1058 - it's included in the default
GateD distribution - there's mention of the 0.0.0.0 notation. Yes, it is
somewhat strange - I'd first been confused by this as well - and it's not a
broadcast route, though it'd initially appear to be so. But then, a lot of
things in TCP/IP are non-orthogonal, and non-predictable.

	Also, Doug Comer's book "Internetworking with TCP/IP" covers this
as well, I believe.

	-rich


---
rich scott						rich@rx7.osa.com
open systems architects, minneapolis			612/525-0000