Subject: Re: illegal network routes and a ponderance
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Pavel Cahyna <email@example.com>
Date: 02/19/2003 16:04:58
> >> But quite aside from what it does to the assumptions underlying IP,
> > What does it do to the assumptions underlying IP concretely?
> That every host that can send a datagram into a network has an address
> in that network. (This is why your suggestion, constructing a
> source-route option, isn't actually a problem, because it doesn't
> involve hosts sending into networks to which they have an interface
> physically connected but in which they do not appear in IP terms.)
I think that even without constructing a source-route option, nothing
would break. In my example, 192.168.2. and 192.168.4. were intended to
be physically distinct networks, connected only by the router with
addresses 192.168.2.21 and 192.168.4.21 . So all this issue would be
internal to the sending host (192.168.2.50) and from the network's point
of view, nothing would change. It would be just a change in the internal
structure of the routing tables. (Admittedly quite useless if
source-routing option is not to be added.)
It's true that this topic doesn't have much common with the rest of this
thread, apart from the word "routing" :-) That's maybe what mislead you.
> >> how would you cut off infinite loops?
> > Isn't the Source Routing option (for IPv4) limited in size? There
> > would be no point in having more loops than this limit.
> True, and that limit _is_ relatively small. Okay, I'm answered.
OK, so I'll have to implement it. Expect patches by the end of
summer :-) .
Thanks for your reply.