Separate attributes vs context-aware software [RE: RPS WG (was Re: [Rps] Re: Latest RPSLng draft)]

On Fri, 2004-01-02 at 03:24, Pekka Savola wrote:
> Hi,
> 
> (I tailed down the Cc: list..)
> 
> On Sat, 27 Dec 2003, Randy Bush wrote:
> > > OK, I now found that the doc did have an IETF Last Call 
> > > in late August/Early Sept.
> > 
> > and there were technical objections which have not been addressed
> 
> Thanks, Randy, for reminding about that.
> 
> Based on some off-list discussion, the technical objections being 
> referred to are the comments from Mark Prior on the list, one of them 
> copied below.
> 
> I'll try to summarize the loooo-ong thread somehow.  Mark believes 
> that the current RPSLng proposition unnecessarily adds complexity to 
> the operators' use of the language, as e.g. IPv4 and IPv6 addresses, 
> peerings, etc. could all be facilitated by redefining the current 
> attributes etc. -- and whichever would be returned could be evaluated 
> based on the context.  As the number of operators using the language 
> is extremely high (and we'd like it to be higher :-) compared to the 
> registry/tool implementations, Mark argues that optimizing for the 
> simplicity to the operators is the most important goal.
> 
> Curtis objects to this mainly based on the fact that this would break 
> the backward compatibility for the clients which do not expect to 
> receive IPv6 data back from their queries.  This could be easily fixed 
> e.g. in tools like IRRToolSet, but that there are a probably a number 
> of hacks built on top of perl, telnetting to port 43, or whatever, 
> which might not be equally fortunate.
> 
> Workarounds to this seem to be adding some kind of version negotiation
> or inclusion to the whois protocol (in the future, maybe using CRISP),
> so that only the clients who signal "yes, I can process IPv6 records!"  
> would activate the IPv6 context processing.  This could also be passed
> to the whois server with an option, like '--use-rpslng' or '-6'. Or
> maybe the client would state which records it wants to get, e.g.  
> '-6' for only v6 records, '-4' for only v4 records, nothing (or -N (or
> something, for "NEW", otherwise only v4 would be returned :) for
> both).  At least RIPE database allows the use of '-Vxxx' verstion
> string to tell about the version of the client software.
> 
> The exact details of how this method would work out would need to be 
> fleshed out.  Any takers?

  I don't believe this would be particularly productive.  These
are implementation details which are really outside the scope of
the RPSLng work.  I don't see the objections to RPSLng as objective
technical issues, but rather subjective preferences.

> 
> Personally, when I was trying to form an opinion on this subject, I 
> found myself thinking that Mark's proposal addresses only IPv4/IPv6 
> case.  It doesn't seem to address how one could specify different 
> unicast/multicast policies, or how to specify different v4/v6 
> policies.  This is also one goal of RPSLng.. even though the major 
> operators who do have multicast or v6 often want their policies to be 
> the same.
> 
> How would this work out if a "more intelligence" model was adopted?
> 
> (I'm personally a bit unsure whether a "more intelligence in the
> tools" -model would or would not make sense at this point, but I think
> I can see both sides of the argument..)

   It is very difficult to judge the impact of such a model without
having a complete census of the various tools in use by ISP's.  For
example, C&W has an extensive set of in-house developed tools which
interact with IRR's.  Is it fair to ask them to hack up their tools
to fit this model?

> 
> Could we get some form of discussion and maybe consensus on what would 
> seem to be the right way forward? :-)

    I think we have already reached the point of "rough" consensus.
Again, I view the expressed objections as subjective preferences rather
than solid technical beefs with the specification.

  Regards,
    Larry


> 
> ===========
> Date: Tue, 23 Sep 2003 09:00:06 +0930
> From: Mark Prior <mrp at mrp.net>
> To: curtis at fictitious.org
> Cc: Pekka Savola <pekkas at netcore.fi>, iesg at ietf.org, rpslng at ripe.net,
>      rps at ietf.org
> Subject: Re: [Rps] Re: Last Call: 'RPSLng' to Proposed Standard
> 
> Curtis Villamizar wrote:
> 
> > How is RPSLng not a superset of RPSL?  Nothing has been removed from
> > RPSL.
> 
> Superset is probably not the best word to describe what I want.
> 
> > The issue is just how do you make transition easiest, supporting older
> > RPSL only clients.  If you just extend import rather than rename it
> > mp-import and extend it, then old RPSL only clients will consider you
> > autnum broken.  If you include mp-import but forget to reflect you
> > IPv4 policy in plain import then the old RPSL client will pick up a
> > subset of you policy.
> > 
> > In either case, extending import, or adding mp-import and putting the
> > extensions there, it would make for a smoother transition if the
> > server code could recognize old clients and feed them with objects
> > translated into plain RPSL.
> 
> I think I have been consistent in wanting the smarts to be in the 
> software and not the language. I would prefer to overload the syntax 
> then create new syntax and let the software work out what is required. 
> We don't use different syntax in computer languages when we want to 
> operate on integers rather than reals so why make the distinction in 
> RPSL? If we have a route object that has a IPv6 address in it surely the 
> software can work out if it wants it or not given it's current context?
> 
> I know you (and others :-) keep on about the old clients but we have 
> left them behind once before in the transition from RIPE 181 to RPSL so 
> do it again but this time lets leave some mechanism behind so that when 
> we need (RPSLng)ng we don't go through this pain yet again. Saying it's 
> not part of the language is a pathetic excuse in my book for not fixing 
> it. If we need a "shim" document to describe the interaction between a 
> server and a client then lets do it. It would make the client software 
> writers life a lot easier if there weren't (at least) 3 server 
> interaction languages to deal with.
> 
> Mark.
> ==========