Subject: Re: complex extensions attacking IETF protocols

From: "Bernard Aboba" <[email-masked]>
Date: Tue, 3 Nov 1998 00:21:56 -0800

>> The IETF traditions of simple protocols, interoperability and design for
>> technical excellence rather than personal/company benefit have resulted
in
>> keeping implementation barriers for a new service reasonably low.

Funny, I have not recently heard of companies implementing routing
protocols (BGP in particular) describing the implementation barriers as
"low." Even simple protocols do not necessarily guarantee simple
implementations -- and if I had to make a criticism stick, it would be that
very often the impact of proposals on the overall architecture is not
considered. The result can be patchwork quilt of protocols that makes
very little sense in totality, while being defensible in the particulars.

>> I believe
>> we should add "keep implementation barriers for a new service low" as a
>> tradition on-par with the others in the IETF.  An attack on this
principle
>> could undermine the other related IETF principles over time.
>

With respect to complex protocols, it is hard to argue for them.
On the other hand, we do seem to be producing a lot of them lately, and in
some cases the complexity seems quite necessary. IPSEC, for example
is not simple. Neither is MPLS. However, both appear valuable, even
though there are considerable barriers to implementation in both cases.

>> I also believe IETF participants should be alert to _individuals_ in the
>> IETF who are deliberately increasing the complexity of IETF protocols
>> contrary to the best technical design.

I am reminded of the proverb "he who lives in a glass house should
not throw stones." It's hard to find anyone who has not at some time made
a proposal that was less than elegant. In general, it seems more productive
to criticize the proposals themselves than to demonize the individuals
advancing them as potential subversives.

After all, one person's wonderful idea is another's "increase in
complexity."

---

From: "mark.paton" <[email-masked]>
Date: Tue, 3 Nov 1998 07:52:51 -0000

I totally agree with you Bernard

-----Original Message-----
From: Bernard Aboba [mailto:[email-masked]]
Sent: 03 November 1998 08:22
To: Marshall Rose; Chris Newman
Cc: [email-masked]
Subject: Re: complex extensions attacking IETF protocols

in

principle

---

From: "mark.paton" <[email-masked]>
Date: Tue, 3 Nov 1998 07:52:51 -0000

-----Original Message-----
From: Bernard Aboba [mailto:[email-masked]]
Sent: 03 November 1998 08:22
To: Marshall Rose; Chris Newman
Cc: [email-masked]
Subject: Re: complex extensions attacking IETF protocols

in

principle

---

From: Jon Crowcroft <[email-masked]>
Date: Tue, 03 Nov 1998 09:54:04 +0100

In message <[email-masked]>, Bernard Aboba type

 >>very little sense in totality, while being defensible in the particulars.

the IAB (as well as the IESG) consider architecture A LOT - the
problem is that we are in an evoliving situation - a prescriptive
architectural approach would be restrictive of innovation - i think a
lot of us feel that an evolutionary approach which permits many flower
to blossom, and then the market garderner to come along and pick the
best, is reasonable.....of course, we can prune completely abherrant
proposals early, but...

of course, the downside of this is proliferation of numbers of
protocols (e.g. tunnel techniques, differnt IGPs, lots of options for
IP on ATM, etc etc) at any given time, but over a period, a
convergence process occurs.....

 >>though there are considerable barriers to implementation in both cases.

yes, indeed.....actually, there are lots of times when the barrier to
implementation is the amount of cross dependence between a set of protocols and
services that is much more complex than in former years of the ietf -
in 88, i did an IP full router impleemntation with an IGP, EGP, ICMP,
and a remote maagement interface etc, in about 1 years effort.....with
3 types of interface/line driver; now, you have to support rather a lot more
to enter the router market credibly :-) (actually you did then - mine
was a throwaway research box)  - similalry with other layers - e.g.
transport protocols, application layer stuff, network management area
etcetc......

but we can distinguish between intra-protocol complexity, and
inter-protocol complexity - the IETF
Has historically been very good at both, but as the world gets richer
in types of networks and applications, the latter just naturally gets
harder -but the former as an engineering design goal should not be
lost...

 cheers

   jon

---

From: Jon Crowcroft <[email-masked]>
Date: Tue, 03 Nov 1998 09:54:04 +0100

cheers

   jon

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From: Masataka Ohta <[email-masked]>
Date: Tue, 3 Nov 98 23:44:34 JST

Jon;

> the IAB (as well as the IESG) consider architecture A LOT -

IAB perhaps, IESG does not. IAB considered, but, not reacted
against IESG.

> convergence process occurs.....

NHRP and MPLS, for example, have failed by themselves, not by
IAB (IESG either) effort.

							Masataka Ohta

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From: Masataka Ohta <[email-masked]>
Date: Tue, 3 Nov 98 23:44:34 JST

Jon;

							Masataka Ohta

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From: Robert Moskowitz <[email-masked]>
Date: Tue, 03 Nov 1998 11:44:58 -0500

>IAB (IESG either) effort.

It is not necessarily a bad thing to let some people see if something would
work and let it fail.  We don't always have to succeed.  And the failures
should be documented for future efforts.

If the port expanders that were used in NCP days were better documented,
perhaps we all would have tried harder to avoid a world of NATs today.

---

From: Robert Moskowitz <[email-masked]>
Date: Tue, 03 Nov 1998 11:44:58 -0500

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From: Tony Li <[email-masked]>
Date: 03 Nov 1998 20:03:15 -0800

John,

> convergence process occurs.....

The problem with this theory is that it fails to match reality.  The fact
of the matter is that the IETF takes a protocol and through the standards
process endorses it.  Now the standards process is not known for being
highly objective, so the result is frequently a political compromise that
embodies the worst of all proposals and the best of none of them.  And then
it gets rubber stamped, distributed in industry, and an installed base then
insures that the quagmire is set in concrete.

If one truly wanted to implement your vision, one would simply have to
accept all proposals for publication, let the market sort through them, and
then only standardize those that were de facto standards.  Not at all what
happens today.

The only credible alternative is one that you preclude: the IAB and IESG
make hard architectural choices, deal with the political consequences, and
reject some alternatives.  Yes, this is restrictive of innovation.  A
coherent architecture inherently insists that there be some restrictions.

However, if the power of the innovation overwhelms the choices made by the
IAB/IESG, then it was clearly a poor choice and the market will fix the
problem.  Think of the market as the court of appeals....

Regards,
Tony

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From: Tony Li <[email-masked]>
Date: 03 Nov 1998 20:03:15 -0800

John,

Regards,
Tony

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From: Masataka Ohta <[email-masked]>
Date: Thu, 5 Nov 98 21:47:48 JST

Robert;

> should be documented for future efforts.

In days of NHRP, some area director said WGs consume so much resource
that they can not be created so easily. I'm afraid the situation is
worse these days.

							Masataka Ohta

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 5 Nov 98 21:47:48 JST

Robert;

							Masataka Ohta