BitTorrent for Linux (Linux.com)
The BitTorrent protocol implements a hybrid client/server and P2P file transfer mechanism. BitTorrent efficiently distributes large amounts of static data, such as installation ISO images. It can replace protocols such as anonymous FTP, where client authentication is not required. Each BitTorrent client that downloads a file provides additional bandwidth for uploading the file, reducing the load on the initial source. In general BitTorrent downloads proceed more rapidly than FTP downloads."
Posted Sep 14, 2005 15:06 UTC (Wed)
by ronaldcole (guest, #1462)
[Link] (11 responses)
Posted Sep 14, 2005 15:15 UTC (Wed)
by spot (guest, #15640)
[Link] (1 responses)
Downloading a DVD iso with a LOT of seeders makes it go very quickly.
Posted Sep 14, 2005 15:29 UTC (Wed)
by arcticwolf (guest, #8341)
[Link]
There is still no guarantee that you'll get the full bandwidth with BitTorrent, of course, but the elimination of single bottlenecks (other than your own connection) that comes with BitTorrent should mean that you're more likely to get sustained high speeds even on very fast connections - assuming that there's enough seeds/peers, of course.
But in the end, the point of whether you get slightly faster downloads over BitTorrent or FTP is moot, anyway. The main point of BitTorrent is not to give users better download speeds, but rather to take the load (bandwidth and otherwise) off of the servers, thus making the distribution of large files to potentially very large audiences so much easier (and less expensive). BitTorrent's change from a top-down (client-server) to a peer-to-peer model is the main difference - it's a democratisation of content distribution, if you will, where even those without deep pockets and big servers are able to publish big files.
Posted Sep 14, 2005 15:20 UTC (Wed)
by pjdc (guest, #6906)
[Link] (2 responses)
More to the point, BitTorrent's primary goal is to scale well as the numbers of downloaders increases, of which it seems to do a good job. Occasionally one gets a very fast download, and that's a nice bonus.
Posted Sep 14, 2005 20:46 UTC (Wed)
by ronaldcole (guest, #1462)
[Link] (1 responses)
Look, it says "in general" which just isn't true. Sorry about that, but it just isn't. I have a T1 line and downloading all 14 Debian ISOs via ftp and via bittorrent took roughly the same amount of time.
Posted Sep 14, 2005 22:26 UTC (Wed)
by mepr (guest, #4819)
[Link]
Posted Sep 14, 2005 18:17 UTC (Wed)
by TwoTimeGrime (guest, #11688)
[Link] (2 responses)
However, with bittorrent I'm downloading from multiple places at once. There are lots of seeds for most Linux ISOs so I can download a 650MB ISO image in about 10 minutes. Like I was saying, that usually doesn't happen with a connection to a single FTP server. Bittorrent has been great for things like Knoppix which are usually served from slow FTP servers.
Posted Sep 14, 2005 20:54 UTC (Wed)
by job (guest, #670)
[Link] (1 responses)
Posted Sep 15, 2005 5:27 UTC (Thu)
by TwoTimeGrime (guest, #11688)
[Link]
In my experience downloading ISOs via bittorrent is always *fast enough*. Also, I find the consistency in speed, and the convenience, outweighs the effort I must expend to find a open and fast mirror (time that I'm having to work and not the computer).
Posted Sep 15, 2005 2:00 UTC (Thu)
by bk (guest, #25617)
[Link] (2 responses)
100 of them are using BitTorrent, downloading from a single seeder.
100 of them are using anonymous FTP, downloading from a server with the same available bandwidth as the BitTorrent seeder.
Guess which group gets the file faster.
Posted Sep 15, 2005 11:58 UTC (Thu)
by job (guest, #670)
[Link] (1 responses)
You could all the mirrors as seeds but that is just treating BitTorrent as a glorified mirror selection tool. I probably know best which mirror I am closest to. As BitTorrent works, there is a lot of administrative overhead keeping track of thousands of ADSL users with their sub-megabit uplinks which are completely uninteresting in real life. When the client works up enough speed to saturate a fat pipe, most of one ISO could have been downloaded at full speed with a simpler protocol.
Don't misunderstand me, BitTorrent is a good file distribution tool. If you want to publish a file with limited resources it is perfect. But the right tool for the right job.
Posted Sep 15, 2005 13:55 UTC (Thu)
by khim (subscriber, #9252)
[Link]
Plus when you download file with bittorrent and it's downloaded you can be sure it's downloaded correctly. Not true for FTP or HTTP.
Posted Sep 14, 2005 16:35 UTC (Wed)
by oseemann (subscriber, #6687)
[Link]
So actually content providers benefit from Bittorrent more than the single user.
Posted Sep 14, 2005 21:19 UTC (Wed)
by zblaxell (subscriber, #26385)
[Link]
I couldn't get single HTTP connections to average much more than a Mbit or two, but after about 15 minutes Bittorrent was saturating the local LAN (i.e. I could have gone faster if the network congestion bottleneck was not *between* my desktop and the firewall ;-).
During the testing I uploaded a gigabyte or two of Sarge ISO's to other people. They were getting about 20mbits between them, although that would have been divided among dozens of users. Still, 1 mbit each wouldn't have been too shabby--at least for the few minutes when I was running the test.
One rather interesting data point (and an illustration of what can happen when Bittorrent goes bad) was that most of the Bittorrent connections for Debian stable Alpha ISO images during the test were to my own system at home. It seems that during that month the only *complete* seed for Debian stable Alpha ISO images known to the Debian bittorrent trackers was in my basement. After a month of trying to get those ISO's via Bittorrent, I downloaded the remaining 3% of the ISO set via jigdo, then put the now-complete image files into Bittorrent and watched as thousands of people hit my server to collect those last few megabytes.
Posted Sep 16, 2005 0:47 UTC (Fri)
by stock (guest, #5849)
[Link]
I've never seen bittorrent download faster than a dedicated ftp download. Sorry.BitTorrent for Linux (Linux.com)
I have. It really depends how many people are seeding the torrent.BitTorrent for Linux (Linux.com)
Whether BitTorrent is faster than (anonymous) FTP is also heavily dependant on your own connection's bandwidth and that of the FTP server (not to mention, in the case of big FTP sites, the FTP server box's memory and all that). On my rather modest ADSL connection (2048/192), BitTorrent downloads generally aren't faster than FTP downloads, unless the FTP server is very loaded (or unless the bandwidth is artificially kept down, as done by some FTP sites); I imagine that things change when you have a faster connection, though, with dozens or even hundreds of megabits downstream.BitTorrent for Linux (Linux.com)
I've had BitTorrent downloads sustain a megabyte a second. Sorry.BitTorrent for Linux (Linux.com)
Perhaps you'll want to sign up with my 56k dial-up service that gives you DSL download speeds. It's only $29.99 a month. What a bargain for U!BitTorrent for Linux (Linux.com)
You're not reading the full context. As he said, results may not be so different on a DSL (usually 1.5Mbps, i.e. equivelent down speet to a T1), although on an ftp server with high client load, I still beg to differ with you, but I was able to download the 14 debian cd's via bittorrent on a 45 megabit connection in less than half an hour (i.e. i started it, took a half our drive, arrived at work, download done). Probably no individual connection was much faster than 1.5 or 3 mbps, but the sum was very quick.BitTorrent for Linux (Linux.com)
That's probably because you don't have a connection that's faster than the FTp server. If you only have 1.5Mbps downstream then, yeah, bittorrent won't be faster than FTP. At work we have a DS3 (45Mbps) for our three buildings. When I download Linux ISO images they are sometimes faster than on a T1 but still aren't taking advantage of the full 45Mbps. Usually this is because the connection I am downloading from doesn't have as much bandwidth as our company does.BitTorrent for Linux (Linux.com)
Then you really need to find yourself a better mirror. I normally saturate faster pipes than yours when downloading (legal) ISOs of Linux software. Most often from my national FTP mirror. BitTorrent doesn't come close to that. It takes too long to even connect to the necessary seeds.BitTorrent for Linux (Linux.com)
By the time I've found a fast mirror I could be done downloading via BitTorrent. In fact, it is for exactly this reason that I use BitTorrent. Different Linux distros are available via different mirrors, not all of them fast, and I usually have to connect to several to see which one is fastest (not always the closest one). Sometimes the fast mirror has reached its maximum number of connections and I must keep trying to connect. I don't consider this to be a good use of my time. As an example, the Knoppix mirrors come to mind. I've tried many of them yet I've never downloaded a Knoppix ISO at greater than 80KB/sec until I used the torrent. It could be that I wasn't hitting a good mirror, but I don't have time to try them all. I certainly don't have time to try every mirror for every distro.BitTorrent for Linux (Linux.com)
200 people simultaneously begin downloading an ISO image of the new Fedora release.BitTorrent for Linux (Linux.com)
Except that's not how it works in real life. Well-regarded free software projects doesn't have problems recruiting as many FTP mirrors as needed. When a new Fedora or Debian release is out, all the users that want pound the mirrors for the ISOs. If one is saturated, more can be added from well connected universities and other places supportive of free software.BitTorrent for Linux (Linux.com)
We are living on different planets then. When FC4 was out I've tried to download with something like 10 mirrors or so. 8 just plain rejected my attempts to connect (to many users connected). 2 accepted but were waay to slow to be actually usable. Then I've put two .torrent files in my Bittornado queue and got DVDs downloaded after half-day.BitTorrent for Linux (Linux.com)
The point of Bittorrent is not a possible download speed increase but a greater scalability. Where the performance of a single ftp site will decrease with the number of users growing, the overall Bittorrent performance will increase.Scalability
I used Bittorrent to test the speed of a new 100Mbit link that was installed in our office a few months ago.BitTorrent for Linux (Linux.com)
i wrote a short page on howto setup your own BitTorrent seeder BitTorrent for Linux NAT HOWTO
behind your iptables firewall :
http://crashrecovery.org/bittorrent/HOWTO.bttr.html
Robert