Re: [iccrg] Disadvantages of TCP connection splitters
Michael Welzl <michawe@ifi.uio.no> Fri, 10 January 2020 10:21 UTC
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From: Michael Welzl <michawe@ifi.uio.no>
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Date: Fri, 10 Jan 2020 11:21:28 +0100
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To: Toerless Eckert <tte@cs.fau.de>
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Subject: Re: [iccrg] Disadvantages of TCP connection splitters
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> On Jan 10, 2020, at 11:14 AM, Toerless Eckert <tte@cs.fau.de> wrote: > > Main downside is that its limited to TCP, and i think it might > be easier nowadays to implement split/merge generically for > 5 tuple flows and not for TCP alone, and the customer gets > the benefits for TCP, DCTCP, SCTP, QUIC, RTP and any other flow. Sure, you’re obviously right, but that’s also potentially solvable with app-level proxying (see draft-kuehlewind-quic-substrate, for example) - I’m more interested in the general congestion control & transport aspects of this. > In most situations you can't simply split the packets without > encap or NAT anyhow because the alternative paths may likely > require different source or dest addresses (dual SP attachment > via broadband/DSL or the like). Once you do have such encap > its typically easier to run your own congestion/retransmission > between merge/split instead of just trying to passivle > observe and analyze the end-to-end TCP signals and figure > out how to deduce the appropriate load-split from them. “run your own congestion/retransmission” - yes, the added flexibility is a big plus here, that’s the plus that I’m trying to weigh against a minus… Cheers, Michael > > Toerless > > On Fri, Jan 10, 2020 at 09:54:07AM +0100, Michael Welzl wrote: >> Hi, >> >> I???ve been thinking a lot about TCP connection splitters lately ( https://tools.ietf.org/html/rfc3135#section-2.4 ). >> >> I???m curious: what are the real practical disadvantages of this type of PEPs that people have seen? >> I'll appreciate any kind of feedback, also anecdotes, but pointers to citable papers would be best. >> >> BTW, let???s keep multi-path apart from this discussion please. My question is about single path TCP. >> >> Cheers, >> Michael >> >> PS: I???m not trying to indirectly hint that such devices would be *always good*. However, the scenarios where they are not strike me as surprisingly narrow, so I wonder if I???m missing more. >> >> _______________________________________________ >> iccrg mailing list >> iccrg@irtf.org >> https://www.irtf.org/mailman/listinfo/iccrg
- [iccrg] Disadvantages of TCP connection splitters Michael Welzl
- Re: [iccrg] Disadvantages of TCP connection split… Toerless Eckert
- Re: [iccrg] Disadvantages of TCP connection split… Michael Welzl
- Re: [iccrg] Disadvantages of TCP connection split… Toerless Eckert
- Re: [iccrg] Disadvantages of TCP connection split… Keith Winstein
- Re: [iccrg] Disadvantages of TCP connection split… Yuchung Cheng
- Re: [iccrg] Disadvantages of TCP connection split… Michael Welzl
- Re: [iccrg] Disadvantages of TCP connection split… Marie-Jose Montpetit
- Re: [iccrg] [nwcrg] Disadvantages of TCP connecti… lloyd.wood@yahoo.co.uk
- Re: [iccrg] Disadvantages of TCP connection split… Kuhn Nicolas
- Re: [iccrg] Disadvantages of TCP connection split… Joerg Deutschmann