Re: [tsvwg] [tcpm] L4S status tracking

Bob Briscoe <> Mon, 11 November 2019 15:23 UTC

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To: Sebastian Moeller <>
Cc: "Scharf, Michael" <>, "Rodney W. Grimes" <>, "" <>, "" <>
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From: Bob Briscoe <>
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Date: Mon, 11 Nov 2019 15:22:56 +0000
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Subject: Re: [tsvwg] [tcpm] L4S status tracking
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      Chambers (British English)

classic adj *1* made of or belonging to the highest quality; established 
as the best. *2* entirely typical. *3* simple, neat and elegant, 
especially in a traditional style. noun *1* an established work of 
literature. *2* an outstanding example of its type. *3* something, eg an 
item of clothing, which will always last, irrespective of fashions and 
fads • /the little black dress, a classic of the 50s/. *4* (*Classic*) a 
celebrated annual sporting event, especially a horse race. See also the 
Classics < 
Classics&title=21st>. *classically* adverb *1* in a classic or classical 
way. *2* so as to be classical.
ETYMOLOGY: 17c: from Latin /classicus/ relating to classes, especially 
the best.

      Merriam Webster (US English)

clas·​sic | \ ˈkla-sik
1a *: *serving as a standard of excellence *: *of recognized value 
classic literary works a classic case study on hysteria
b *: *traditional 
<>, enduring 
<> classic designs
c *: *characterized by simple tailored lines in fashion year after year 
a classic suit
2 *: *of or relating to the ancient Greeks and Romans or their culture 
*: *classical <>
3a *: *historically memorable a classic battle
b *: *noted because of special literary or historical associations Paris 
is the classic refuge of expatriates
4a *: *authentic <>, 
authoritative <> 
a classic study of eyewitness accounts
b *: *typical <> a 
classic example of chicanery a classic error

Responses inline...

On 06/11/2019 23:04, Sebastian Moeller wrote:
> Dear Bob,
>> On Nov 6, 2019, at 19:12, Bob Briscoe <> wrote:
>> Sebastien,
>> On 06/11/2019 07:18, Sebastian Moeller wrote:
>>> Hi Bob,
>>> On November 6, 2019 1:22:44 AM GMT+01:00, Bob Briscoe
>>> <>
>>>   wrote:
>>>> Michael, Rod,
>>>> Altho non-L4S is a reasonable idea, I think it has more of a negative
>>>> connotation than classic.
>>>          [SM] It does have the advantage though of being a testable, with classic all we know is you are talking about something that came before.
>> Which is a good starting point, because that's what is intended.
> 	[SM] I know that this is what you intend, but it is the test of time that makes classics classics, no amount of wishful thinking of the new-kid-on-the-block will relegate the reigning champion into classic mode, your solution really has to a) be better, and more importantly b) supersede that champion in the first place.
[BB] Not at all. Because classic has no hint of inferior. Quite the 
opposite according to the dictionaries.

This is an excellent demonstration of how any term, even a good positive 
one, attracts a negative connotation as soon as it is used to mean "the 
things that are claimed to be improved on". This says to me that the 
quest for a better word than classic will be fruitless.

Just like how kids quickly started to use the word 'special' as a term 
of abuse soon after the phrase "children with special needs" was 
introduced by well-meaning people.

>> Plus it already has a slightly positive natural meaning of "something robust that has stood the test of time". Then it is defined precisely for the context of each L4S doc, e.g.:
> "Classic service:  The 'Classic' service is intended for all the
>        behaviours that currently co-exist with TCP Reno (e.g.  TCP Cubic,
>        Compound, SCTP, etc)."
> Reading this implies that TCP Reno is not in the classic set, as you define that set as those co-existing with Reno and that is does not include Reno. But really =you can define what ever you want, but to have others accept your definition it better be useful.
[BB] Good point. I'll certainly fix that along with the problems that 
Rod pointed out.

>>>> For example, if you did define the name "non-iPhone" to mean phones
>>>> such
>>>> as Android, Windows, etc, then you would expect the phrase "non-iPhone
>>>> knock-off products" to mean "fake Android and Windows phones". However
>>>> the constituent elements "non" and "iPhone" already have a meaning of
>>>> their own, so in the context of this phrase, it means "fake iPhones",
>>>> which is the opposite of what you wanted.
>>>          [SM] That is completely besides the point, it made me smile though and think about that passage in Alice in Wonderland about the meaning of words.
>> [BB] Please try to understand why this is very much the critical issue (more important than the negative connotation question, which is subjective).
> 	[SM] Your are debating me to score points here, are you?
[BB] Not at all. We need a context-independent meaning. I am raising a 
practical problem with choosing a name that contains an element ("non-") 
with a natural meaning that will change the presumed meaning of 
"non-L4S" dependent on context.

> You sort all flows into two categories, those that show L4S-style response to ECN signals and those that do not. The first group is reasonably homogenous, the second is not. So calling the second set non-L4S-style seems totally reasonably to me, unless you find another PROPERTY that defines that set, and no "classic" is not a property.
[BB] Non-L4S would be reasonable, were it not for its context-dependence 
problem. On what basis can you say that classic is not a property, when 
it is (both as defined for the L4S drafts, and as a well-understood 

> This is getting as ridiculous as your 17 year old car example....
>> I believe you are thinking in the context of all traffic. Let's call that set A. And let's call the set of all L4S traffic L1.
>> Then in this context, "Non-L4S" naturally means A - L1.
>> However, consider another context, say the context of all Low Latency traffic, that we'll call L2. This was the context of the example I found in the draft. In that context, the term "Non-L4S" already naturally means L2 - L1.
> 	[SM] Well, for me L4S traffic is traffic that show a "linear" response to CE markings instead of a "multiplicative" (we can argue whether that is the correct definition, but it sure beats the what ever I feel is L4S definition you seem to propose)
[BB] Are you really meaning to say that I don't know the theoretical 
grounding of my own research as well as you do?

BTW, Reno, Cubic and L4S responses to congestion are all multiplicative.

>   and in that sense the set theoretical observations boil down to your first formulation. The fact that the L4S draft allows for your second formulation is a defect in that draft. The other stuff is not L4S but rather LoW-Latency traffic (which might be qualified to share L4S low latency queue with true L4S traffic).
>> So the term "Non-L4S" already has the intended meaning of Classic, but only in one context (A), and it has other meanings in every other context.
> 	[SM] If you insist on overloading definitions, be my guest to keep the pieces once things break.
[BB] The current draft does not overload any definition of 'non-L4S'. It 
uses its natural meaning of "traffic that is not L4S" in the reduced 
context of the low latency queue. That's why I picked it as an example 
of a context-dependent word that would not be useful as a 
context-independent name.

>> It's a very bad idea to choose a name that already has a natural meaning that can be different to what you want to define the name to mean.
> 	[SM] I apologize I was not thinking about "in Wonderland" but about Through the Looking Glass ( :
> "'When I make a word do a lot of work like that,' said Humpty Dumpty, 'I always pay it extra.'"
> L4S has exactly zero natural meaning, so please stop pretending it does.
[BB] When expanded it completely describes what it means: "Low Latency 
Low Loss Scalable throughput".


Bob Briscoe