The IP Over NBMA (ION) Archive

[Tim Dwight <0006078043@mcimail.com>]

I see that my posting was resurrected, and can't resist a small 
response.  I realized after a few exchanges that this was a case where
both sides were right... the difference was in how we imagined utilizing
the CSR.

So I agree with Mr. Fujikawa's analysis below.  If this is the way
you structure your network, the CSRs will find the same route that 
would be found via NHRP.  

The difference I had with Mr. Ohta, was because I didn't (and still
don't) intend to structure my network in this way.  In my model, there
are cases where NHRP could find better routes than the CSR can find.

If you think my model is dumb, fine, I'm happy to agree to disagree.
But I would also point that:

     1) that the fact that NHRP might not add value in networks laid 
        out like the one below, does not imply that it cannot add value
        in other topologies.

     2) It is unlikely that the IETF can force the whole world to 
        deploy ATM as described below.  A variety of configurations,
        perhaps including this one, will be deployed.  If it can be
        shown that NHRP adds value in some configurations, and that
        those configurations are reasonable enough to be likely to 
        be deployed, then it's "useful".

tim

> I don't think
> there are so many shortest ways that a CSR can't find.
> Because sunbnets with CSRs shuld be constructed as follows:
> 
>      subnet A                   subnet B
> +------+  +------+  +---+  +------+  +------+  +---+  
> |switch|--|switch|--|CSR|--|switch|--|switch|--|CSR|--
> +------+  +------+  +---+  +------+  +------+  +---+  
>     \       /                  \       /              
>      +------+                   +------+              
>      |switch|                   |switch|              
>      +------+                   +------+              
>         |                          |                  
>       +----+                     +----+               
>       |host|                     |host|               
>       +----+                     +----+               
> 
> Note that 
> this configuration is almost same to that of a network
> consisting of ethernet hubs and conventional routers.
> ---------------------------------------------------------
> FUJIKAWA, Kenji @ Dept. of Info. Sci., Kyoto Univ., Japan
>                   TEL +81 75-753-5387 FAX +81 75-751-0482
>                        e-mail magician@kuis.kyoto-u.ac.jp


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