[e2e] end of interest

David P. Reed dpreed at reed.com
Sun May 11 07:52:10 PDT 2008

Snooping honors the Layeristi - granting them rhetorical power they 
never deserved.   It sounds like "cheating" or "illegal" operation.  The 
Internet was born without layers - it used architectural framing 
differently (e.g., one arch principle illustrative: encapsulation is not 
layering, and even survives as IP gets encapsulated in TCP port 8 VPNs, 
much to the chagrin of the Layeristi purists who explain it as a "bug", 
rather than looking at its roots in passing IP datagrams over SNA and 
NCP virtual circuits).

I'd suggest that first-principles thinking is harder than Jon thinks.   
It's not just a matter of choosing sides in a war, or acting as an arms 
merchant to both sides.   It's about thinking more squarely about the 
real underlying issues that comprise communications . In fact, as some 
of us have suggested, perhaps the idea that communications can be 
considered as a "pure" architectural/linguistic frame independent of 
storage and computation and sensing is the real issue we ought to be 
addressing today, with pervasive comms/storage/computational elements 
capable of all three.

John Day wrote:
> At 9:08 +0100 2008/05/11, Jon Crowcroft wrote:
>> nice example of 0nership by warring protocol layer factions
>> mesh wifi people need to learn to do layer 3 snooping
>> same way telecom people did...
> The need to do snooping is an indication of the current model's 
> inability or refusal to innovate.  A failure to dig more deeply into 
> the model.  (Or a fear to challenge their religion.)
> (It turns out once there is a complete architecture, not one of these 
> DOS look-a-likes, snooping isn't necessary.)
>> there's a great e2e topic -
>> we have sort of gotten out of the
>> denial phase on middle boxes and
>> we're probably ok with multicast's niches now ...
> Middleboxes are alos an artifact of an incomplete architecture.  In a 
> full (shall we say, a wff) architecture, they aren't necessary.
>> but should we raise the
>> art of _snooping_ to being a
>> first class component of any decent
>> postmodern internet architecture?
> No, snooping is an admission of failure.  Calling it a component of a 
> "decent" internet architecture is merely making excuses for our failures.
>> knowing
>> multicast group members locations from lookin at IGMP traffic from 
>> "below"
>> is one exxaple (think dslams too) but another would be
>> P2P aware Traffic Engineering, for example
> Recognizing that a multicast address is the name of a set deals with 
> most of this.  (Of course, this means that strictly speaking multicast 
> addresses aren't really addresses but names.) A multicast or anycast 
> address must always resolve at some point to a normal address.  The 
> idea of a multicast address as an ambiguous address is fundamentally 
> broken.
>> "layer violations" as taught in protocls #101 has traditionally
>> been restricted to upper layer tweaking layer-2 operating parameters
>> (think Application/TCP causing Dial up), rather than
>> vice versa - but the other way round stretches
>> programming API paradigms more athletically
>> so may be condusive to progress...
> If I understand what you are alluding to, this is addressed by not 
> ignoring the existence of the enrollment phase in communication.
> What I have found is that in a wff architecture there are no need for 
> layer violations.  In other words, if you have layer violations, you 
> are doing something wrong some place.  Either in how you are trying to 
> do what you want to do, or in what you think a layer is.  In this case 
> it seems to be a bit of both.
> Take care,
> John
>> In missive <1210445625.6167.138.camel at jg-laptop>, Jim Gettys typed:
>>  >>On Sat, 2008-05-10 at 12:18 -0400, David P. Reed wrote:
>>  >>
>>  >>> There are huge aspects of that future that depend on getting the
>>  >>> low-level abstractions right (in the sense that they match real 
>> physical
>>  >>> reality).  And at the same time, constructing a stack of 
>> abstractions
>>  >>> that work to maximize the utility of radio.
>>  >>>
>>  >>
>>  >>First hand reality in the OLPC project: use of multicast/broadcast 
>> based
>>  >>protocols when crossed with nascent wireless protocols (802.11s), can
>>  >>cause spectacularly "interesting" (as in Chinese curse) interactions.
>>  >>
>>  >>First hand experience is showing that one had better understand what
>>  >>happens at the lowest wireless layers while building application
>>  >>middleware protocols and applications....  Some existing protocols 
>> that
>>  >>have worked well on wired networks, and sort of worked OK on 
>> 802.11abc
>>  >>networks, just doesn't work well (or scale well) on a mesh 
>> designed to
>>  >>try to hide what's going on under the covers.
>>  >>
>>  >>While overlays are going to play an important role in getting us 
>> out of
>>  >>the current morass (without transition strategies, we're toast; 
>> that was
>>  >>what got the Internet out of telecom circuit switching as the only
>>  >>mechanism), I have to emphatically agree with Dave that we'd 
>> better get
>>  >>moving on more fundamental redesign and rethinking of networking....
>>  >>                           - Jim
>>  >>
>>  >>--
>>  >>Jim Gettys <jg at laptop.org>
>>  >>One Laptop Per Child
>>  >>
>>  cheers
>>    jon

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