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uTorrent To Build In Transfer-Throttling Ability
vintagepc writes "TorrentFreak reports that a redesign of the popular BitTorrent client uTorrent allows clients to detect network congestion and automatically adjust the transfer rates, eliminating the interference with other Internet-enabled applications' traffic. In theory, the protocol senses congestion based on the time it takes for a packet to reach its destination, and by intelligent adjustments, should reduce network traffic without causing a major impact on download speeds and times. As said by Simon Morris (from TFA), 'The throttling that matters most is actually not so much the download but rather the upload – as bandwidth is normally much lower UP than DOWN, the up-link will almost always get congested before the down-link does.' Furthermore, the revision is designed to eliminate the need for ISPs to deal with problems caused by excessive BitTorrent traffic on their networks, thereby saving them money and support costs. Apparently, the v2.0b client using this protocol is already being used widely, and no major problems have been reported."
I'm sure ISPs such as Comcast will find another reason to suggest they need in interfere with network management. just give them a little bit of time to put their heads together with the guys at RIAA.
-- All this knowledge is giving me a raging brainer.
The summary says that the protocol is already out there, and "no major problems are reported." So how about "and congestion is being reduced, and here is how we know it?"
Currently hooked on AMP
Let me explain:
a) That's "The Fine Article", you insensitive clod!
b) You must be new here.
c) In light of b) Articles=bad. Summaries=good.
Evolution - Est. 4500000000 B.C. Don't piss in the gene pool.
shouldn't TCP do that by itself?
Anyway, I consider this is a good thing, it'll probably increase goodput (less outdated, duplicate packets, preferring "closer" networks).
This is probably aimed at average BItTorrent users, i.e. they're on Windows. I highly doubt Windows has the wide variety of TCP congestion management protocols that are available in the Linux kernel. If I am wrong about that, please correct me as I had a really hard time confirming this for certain. It's not exactly a "common support question" that you can easily Google for, or maybe your Google-fu is stronger than mine. I think Windows uses an implementation of Reno and that's it. Hence, the need to build these features into the clients.
Then there's the issue that to a TCP congestion protocol, all traffic is likely to be equal in its eyes. It won't know that torrent traffic should receive lower priority whenever it conflicts with something else, VOIP apparently being the classic example. For that you need actual QoS. So the client itself will now measure latency to help determine this.
Also, I doubt this will eliminate an ISP's excuses for throttling traffic. In terms of bandwidth saturation and network capacity, I highly doubt your ISP really cares whether your BitTorrent client is fully saturating your upstream by itself, or whether it uses only the bandwidth that something else doesn't need. In either case, you'd be maxing out your upstream pipe which is what they might concern themselves about.
Bittorrent spawns a huge number of connections. If the OS (or ISP) gives equal bandwidth to each TCP stream, your connection to youtube gets about as much as each one of your 25 bitorrent connections, which destroys the streaming video, voip, or even normal web surfing. I would LOVE it if this provides a solution. (I would be even happier if ToS flags were widely honored, but that has never happened, so I don't know why it would happen now).
Seriously though, this is a good thing. I don't know why the story is tagged "your rights online"
Short answer, No. TCP doesn't back off until packets are lost. uTP looks for latency increases which happen before packet loss (and therefore, before TCP congestion control kicks in) and throttles itself preemptively. Put another way, TCP treats all senders as having an equal right to bandwidth. uTP doesn't want to assert an equal right to bandwidth, it wants to send and receive in the unused portion of the available connection.
Don Negro
Perl 6 will give you the big knob. -- Larry Wall
Most clients have you set a fixed upload speed. Some try to do this automatically, while most have you set it manually. This isn't perfect - if you set it to use 80% of your upload, and you are using more than 20%, things will get slow. If you use less than 20%, you'll have some amount idle and being wasted. Some rely on something like monitoring ping to some specific service.. if ping is higher, throttle back. If ping is low, increase speed. Again this isn't perfect because it relies on a single host and route to determine your speed.
uTorrent's new protocol requires no action from the user, no automatic bandwidth tests, and no outside service. It is designed to always use the optimal speed, while never interfering with foreground tasks.
It has been a while since I read it, and when I read it I was very very tired, but my understanding is that it tags each packet with a high-precision send time. So if we have two packets, A and B, A will sent at 100ms and B will be sent at 300ms. So you know they were sent 200ms apart. The _receiver_ then notices that he receives them 400ms apart, so there is 200ms of lag which means it should be throttled back. It tries to keep the amount of lag 50ms. Again, I could be completely wrong :D
Since it is based on UDP and not TCP, it also solves the problem of Comcast sending fake RST packets to make each client think they wanted to disconnect from eachother.
I dont' think you quite understand that word you used there. Hulu/pandora are the OPPOSITE of multicast.
You have no clue what multicast is, do you? Please stop using that word until you get a fucking clue about what it is.
Hulu and Pandora are NOT multicast. If they were, it would put less of a strain on their networks.
I've owned an ISP and I can tell you, P2P applications like BT put a BIG strain on the network. You saying its a myth doesn't make it so. Just shows that your an idiot who talks out of his ass.
That being said, instead of bitching about network congestion like Comcast does, I would upgrade my network to keep up with the demand. I got a lot of customers that way. Long-term, its the better strategy.
THEIR arrogance is astounding? How about yours? They are working FOR FREE. You are merely complaining. Get your hands dirty and start doing some work yourself.
You can suggest things all you want, but once you start insulting someone for their free work, you've crossed a line. Nobody is forced to use their client. There are dozens of decent clients and probably hundreds of open source ones.
As for their choices, they will work on what's more important to them, I'm sure. Since they don't need this 'local' feature, they haven't got much incentive to actually work on it.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
No bittorrent client picks one peer, and downloads everything from them... Instead, it connects to a large number of peers, and downloads from all of them.
If you can download from your neighbor 100X faster than you can download from someone across the planet... good. You'll get 100 chunks from your neighbor, for every 1 you get from the foreign country. No programming required.
There's ample opportunity for either to be equally fast. Crossing an ocean increase latency, but if the link isn't horribly oversubscribed, can provided speeds faster than you can handle. So, your neighbor might have 100 other people requesting the same torrent as you, for the same reasons, while the kid in Kazakhstan may have a great internet connection, which is barely being utilized, and this while international traffic is down. This is not international calling... you don't save money by not fully utilizing that transoceanic link.
Also, ISPs brought this on themselves. I've long advocated ISPs allowing unlimited speeds between subscribers, and only limiting the uplink speeds to whatever you've subscribed, but they almost never do. If they did, see above... any peer-to-peer protocol would naturally download almost everything from local sources, without any added intelligence on its part. You wouldn't have to write it in to every single app.
You could implement it easily, if you're willing to restrict yourself to neighboring network addresses in lieu of all else. If you want some fancy weighting to decide how important locality is versus absolute speed, completeness, etc. then you're talking about a major project.
Besides that... A good network admin could do the job in an hour as well, with no need to rewrite any of the applications.
That's baseless and utterly ridiculous.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
THEIR arrogance is astounding? How about yours? They are working FOR FREE. You are merely complaining. Get your hands dirty and start doing some work yourself.
You can suggest things all you want, but once you start insulting someone for their free work, you've crossed a line. Nobody is forced to use their client. There are dozens of decent clients and probably hundreds of open source ones.
As for their choices, they will work on what's more important to them, I'm sure. Since they don't need this 'local' feature, they haven't got much incentive to actually work on it.
First of all, they're not working for 'free', uTorrent is owned by BitTorrent Inc, a for-profit company. Initially it was free, but it's now developed by a corporation. Those devs are salaried employees.
More importantly, uTorrent depends on and uses infrastructure that is not free, by any stretch of the imagination. International links are $billions expensive.
So by your logic, just because a user can download their client for free, it gives Bittorent Inc carte blanche to do anything at all they want, including shit all over the internet infrastructure?
How the fuck does it make sense for a company who's product uses something like 30% of the total internet bandwidth to not make an hours worth of effort to minimize their impact on said infrastructure? Their product in its present state is so harmful that ISPs are buying millions of dollars worth of equipment to throttle it, and with good reason.
Read up on the Tragedy of the Commons and get a clue.
Compare their behavior to the largely free, open, and volunteer efforts of the dedicated people who worked on the early Internet protocols like DNS and NNTP. These were systems designed to scale, use bandwidth efficiently, and 'play nice'.
What happened since then? Why is it acceptable now to design a protocol that is maximally inefficient? Why would anyone support this kind of behavior?