[e2e] [SPAM] opening multiple TCP connections getting popular

Jon Crowcroft Jon.Crowcroft at cl.cam.ac.uk
Wed Aug 29 14:44:52 PDT 2007

1.  I think one good thing about Bob Briscoe's rant about the fairness religion 
is that it does question if we should be worrying about it so much - 

I personally think that the net mainly survives because
 access links in most the world are slower than the core and servers 
(and p2p systems) are balanced: if you like, 
Van's idea of packet conservation applies at the higher level of 
file transfer/upload v. download, explicitly so in bittorrent's tit-for tat

2. I think you are right to suggest people will (and already do) script
downloading more videos than they can watch - 

Netflix and similar services already deliver a standing N films a day 
to many people who timeout and send some back without viewing;
if I have enough storage, i might do the same - 

On the other hand, 
if I am part of a video distribution swarm/torrent, 
then the people that do this will be acting to REDUCE load because 
they will serve the local subset from the majority of people 
who just want the nearest uncongested set of servers/peers, 
so if some fraction of uber-users are greedy, 
they actually benefit the community in a community based content distribution system 
(eg. seeds/supernodes/superpeers etc)

3. If (and some places, like japan where I am right now, already have) 
we move to a lot of fiber to the home, 
then the edge access speeds may outdistance the core once again 
(as in the late 80s and early 90s), 
then the e2e congestion control stuff will be important again - 

For me there are two parts to the fairness:
a) Whether you want proportional, or max min, or some other type of fairness policy - 
This comes down to different business models, 
if you are a service provider, and 
different social policies (market capitalism or welfare state) 
if you are a government/regulator etc
b) Whether its applied on a per user, per session, or per internet-portal 
(access line) granularity, or even at larger granilarities (institutional)
c) The inverse of this is that there has to be a mechanism at each level to
prevent sybil/aliasing identity attacks

4. Note:
One of the goals in some of the FIND projects working on 
large scale net virtualisation is to provide different granularity virtual internets...
which is good as it says we dont have to argue, 
but we provide all the parallel universes you want...

In missive <aa7d2c6d0708291422o4f554fefta367f9209a4e32f8 at mail.gmail.com>, "Lachlan Andrew"

 >>Greetings John,
 >>On 29/08/2007, Jon Crowcroft <Jon.Crowcroft at cl.cam.ac.uk> wrote:
 >>> tcp is not about resource allocation
 >>So why is there so much talk about ensuring everything is "TCP
 >>friendly"?  The TCP community certainly seems to think TCP is about
 >>resource allocation, even if the E2E community doesn't.
 >>My reply to David Reed seems to have been blocked by the e2e's header
 >>rules (my mailer automatically puts co-recipients like e2e in the "Cc"
 >>field, which doesn't get through), so here it is again.
 >>Greetings David,
 >>On 29/08/2007, David P. Reed <dpreed at reed.com> wrote:
 >>> But a deeper question is this: if I want a movie each day, and my daily
 >>> average rate of consumption is not going to change because I can't watch
 >>> movies faster than my eyeballs work, why is this going to be a big
 >>> problem?   Is there any evidence of people downloading movies that they
 >>> don't watch?
 >>Yes, there is.  Just last weekend I was talking to someone who claimed
 >>that he is morally justified in downloading pirated video because he
 >>doesn't watch it, and just collects it.
 >>The "limited demand" argument seems to assume:
 >>1. Video definition doesn't keep getting higher (home IMAX anyone?)
 >>2. People don't "channel surf", and download 10 different videos just
 >>to select which to watch
 >>3. Spikes in demand are no more harmful than smoothed demand.
 >>The same logic can be applied to say that we can use any non-standard
 >>TCP congestion control, which the IETF is so hesitant to standardize.
 >>Surely it is better to give people an incentive to download movies at
 >>uncongested times (and not causing undue congestion by their own
 >>actions).  Congestion pricing does just that.
 >>Lachlan Andrew  Dept of Computer Science, Caltech
 >>1200 E California Blvd, Mail Code 256-80, Pasadena CA 91125, USA
 >>Phone: +1 (626) 395-8820    Fax: +1 (626) 568-3603



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