Subject: Re: illegal network routes and a ponderance
To: Pavel Cahyna <>
From: Seth Kurtzberg <>
List: tech-net
Date: 02/19/2003 09:59:46
For better or worse, source routing is disabled in most routers for security 

On Wednesday 19 February 2003 07:33 am, Pavel Cahyna wrote:
> Hello,
> > > Why is this (having a route pointing to a gateway that's not on net
> > > for any interface) not supported, even if there is a route for this
> > > gateway pointing at another gateway which is on-net?
> >
> > My guess is, because it does not match IP's routing model, so whoever
> Well, it seems to match the routing model of source routing, but I would
> like to know for sure, as I'm not very familiar with source routing.
> > > I. e. could the routing table be searched recursively, until a
> > > directly-reachable gateway is found?
> >
> > It could.  But quite aside from what it does to the assumptions
> What does it do to the assumptions underlying IP concretely?
> > underlying IP, how would you cut off infinite loops?
> By specifying a maximum loop count, as it is with symlinks.
> Isn't the Source Routing option (for IPv4) limited in size? There would
> be no point in having more loops than this limit.
> Thanks	Pavel

Seth Kurtzberg
M. I. S. Corp.