Re: TCP "experiments"
Jon Crowcroft <[email protected]>
| Newsgroups | gmane.network.end2end |
|---|---|
| Message-ID | <[email protected]> |
yes, fairness is a key idea which has to be linked with some accountable entity here's an interesting relevant paper (i think:) http://www.sigcomm.org/ccr/papers/2008/January/1341431.1341434 In missive <[email protected]>, Marco Mellia typed: >>If you want an example where a change would be not "fair", you can = >>consider YouTube. >>Now they start to use more than one TCP connection to serve the video. >>This avoids that the application gets stuck because the TCP connection = >>gets stuck. >>In case of competing traffic (and congestion), YouTube client will = >>download in parallel from multiple connections (we have seen up to 5). >>Thus sharing capacity is not fair against other concurrent traffic. >>You may say that Video is not best effort, so why not. >>But in a scenario where you use YouTube and I use MyTube, you'll see, = >>and I'll not see :( >>You are more aggressive, and get a larger share of capacity. >> >>Same for TCP initial window. You use 10, I use 2. You are more = >>aggressive. I suffer from additional losses/delay because of you (in = >>case we share the same link). >> >>As said, weighting the pros against the cons is not easy. >> >>Anyway, I found it funny that we can discuss this forever. But actually = >>no one has the right/power/control of imposing anything on the Internet.=20= >> >>Basically, it's a perfect anarchy, where everyone is allowed to = >>do/deploy whatever he thinks it's good for him.=20 >>I push more, I get more. I don't care if you get hurt=85 >>Would be nice to have a system where some judge can say that you are = >>pushing too much, and provide a punishment for you. But this seems quite = >>impossible here=85 >> >>Ciao >>M >> >> >> >>> In missive <[email protected]>, Marco = >>Mellia typed: >>>=20 >>>>> Jon, >>>>>=20 >>>>> I think no one is saying that big companies are doing dumb things. = >>It's =3D >>>>> just that the Internet is a really shared infrastructure. >>>>> Unless resources are infinite (which may be actually the case for = >>Google =3D >>>>> :)), gaining something somewhere comes at the expenses of loosing =3D >>>>> something else somewhere else. >>>>>=20 >>>>> Considering TCP, it is easy to show that "I can gain". It is much = >>harder =3D >>>>> to show "who else is loosing". >>>>> And weighting the plus and the minus is even more complicated. >>>>>=20 >>>>> M >>>>>=20 >>>>>=20 >>>>> --=3D20 >>>>> Marco Mellia - Assistant Professor >>>>> Dipartimento di Elettronica e Telecomunicazioni >>>>> Politecnico di Torino >>>>> Corso Duca Degli Abruzzi 24 >>>>> 10129 - Torino - IT >>>>> Tel: +39-011-090-4173 >>>>> Cel: +39-331-6714789 >>>>> Skype: mgmellia >>>>> Home page: http://www.tlc-networks.polito.it/mellia >>>>>=20 >>>>> On Jul 30, 2013, at 1:34 AM, Jon Crowcroft = >><[email protected]> =3D >>>>> wrote: >>>>>=20 >>>>>> the nice thing about a lot of the big cloud/web service outfits=3D20 >>>>>> is that they run a huge _range_ of applications so a point = >>solution=3D20 >>>>>> tcp optimised for just one thing that=3D20 >>>>>> harmed the common case uses of TCP would be ruled out -=3D20 >>>>>> =3D20 >>>>>> if you think about the mix of map/reduce,=3D20 >>>>>> video streaming, social net, searches, gmail, gfs, google docs, etc = >>=3D >>>>> etc=3D20 >>>>>> (and similar mixes for microsoft bing + hotmail + azure etc;=3D20 >>>>>> and similar for apple iCloud, appstore, and similar for, >>>>>> oh, i dunno, maybe even facebook),=3D20 >>>>>> then I doubt very much we'd see them do something >>>>>> as narrowly dumb as people seem to imply here=3D20 >>>>>> (or deploy someone else's dumb narrow hack either).... >>>>>> =3D20 >>>>>> as for impact between different cloud/web service providers >>>>>> (e.g. google being smart enough to optimise a TCP hack for all that = >>=3D >>>>> stuff >>>>>> but still harm Amazon's traffic for book/cd buying, EC2, cloud = >>music =3D >>>>> player >>>>>> etc etc, that would be incredibly ingeneiously dumb,=3D20 >>>>>> but also unlikely, since a major google's revenue depends on=3D20 >>>>>> people finding stuff on _other servers,=3D20 >>>>>> and finding those other services useful,=3D20 >>>>>> so it would be kind of silly to auction advert space to the highest = >>=3D >>>>> bidder=3D20 >>>>>> iand deliver those adverts in a way that broke the advertised =3D >>>>> things.... >>>>>> =3D20 >>>>>> [I suppose you could deliver adverts that broke TCP services to >>>>>> servers that hadn't paid you to advertise them - that'd be pretty >>>>>> super duper whacky type of cyberwarfare game some folks at the NSA >>>>>> probably have fun thinking up..... >>>>>> =3D20 >>>>>> maybe Huawei could deploy some DPI-based filter to harm succesful =3D= >> >>>>> businesses only >>>>>> so as to bring down the whole capitalist imperialist western =3D >>>>> civilisation....oh no, >>>>>> wait, they need our net to work so they can sell us their = >>routers... >>>>>> =3D20 >>>>>> In missive <[email protected]>, Joe = >>Touch =3D >>>>> typed: >>>>>> =3D20 >>>>>>>> =3D20 >>>>>>>> =3D20 >>>>>>>> On Jul 29, 2013, at 11:14 PM, Jon Crowcroft =3D >>>>> <[email protected]> wro=3D3D >>>>>>>> te: >>>>>>>> =3D20 >>>>>>>>> google have extremely good instrumentation - >>>>>>>> =3D20 >>>>>>>> They can now see how my PC talks to amazon.com now? >>>>>>>> =3D20 >>>>>>>>> their shareholders would get upset if they deployed things that = >>=3D >>>>> broke >>>>>>>>> the world badly - >>>>>>>> =3D20 >>>>>>>> Even if they made Google 0.01% faster? And increased ad revenue = >>as a =3D >>>>> result?=3D3D >>>>>>>> And stock value or dividends? >>>>>>>> =3D20 >>>>>>>>> that's the NSA's job. >>>>>>>> =3D20 >>>>>>>> Sound like you're referring to my first point above :-) >>>>>>>> =3D20 >>>>>>>> Joe=3D3D20 >>>>>>>> =3D20 >>>>>> =3D20 >>>>>> cheers >>>>>> =3D20 >>>>>> jon >>>>>> =3D20 >>>>>=20 >>>=20 >>> cheers >>>=20 >>> jon >>>=20 >> cheers jon