Re: noid and applications (generic requirements from applications)

[Patrik Fältström <paf@cisco.com>]

On 2003-11-13, at 14.48, Tony Li wrote:

> That is going to be exceedingly difficult.  As long as we
> are using IP addresses in applications and we are hiding
> the actual reachability of the address from the application,
> we are guaranteed to be allowing an application to pass along
> an unreachable address.
>
> Note that this is a result of the layering violation of
> passing around an IP address in the application.  Asking us
> to warp the world to support architectural mistakes strikes
> me as suboptimal.

The reason I ask is because I want to know what we will get at the end 
of the day with the noid proposal.

Today, the idea is that the IP address as well as the FQDN is globally 
unique and have the properties described.

|    (A=B) and (B=C) gives (A=C) where '=' is "can communicate with"
|
|  and
|
|    (A->B) gives (B->A) where '->' is "can send data to"

What I understood from the noid draft is that what we today call IP 
addresses (what is above L2, used in the arp requests etc) can be 
rewritten and because of this doesn't have the properties above.

My question was whether the new identifier will have the properties 
above, so an application instead of doing layering violations on 
FQDN+IP should do the same kind of violations on FQDN+Identifier?

Else it will be extremely hard to "fix" protocols like ftp and 
everything which controls RTP streams.

I think the discussion whether those protocols are designed in a 
correct or wrong way will not help, as you and myself possibly have the 
same view -- even though there are rumors there are differences in how 
hot it is in hell.

IF the above properties are valid for at least one of the identifier 
"layers" in noid, fixing applications and protocols we have today will 
be much easier.

   paf