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Caching Torrent files in DNS
bodin writes "This is a proof of concept version of BitTorrent where the torrent files are transported over DNS. This will of course bog down BIND servers all over the planet. Everyone should be thankful that the files are not sent over DNS."
Great I get to see this article posted just before the internet slows to an unacceptable crawl and names stop resolving.
Bloody hell, that guy has awful spelling!
And he's coded what is obviously the *worst idea ever!*
Do you want to shoot him or shall I?
I'm amazing. You aren't. SUCK IT
I know its sort of a chicken / egg thing... but can someone explain exactly why BT itself can't be used to distribute torrents, or to share the bandwidth of tracking?
Seriously. I don't pretend to understand 100% of the technology involved, but it seems pretty clear even to me that:
- DNS servers, as the name implies, are for serving DNS information.
- For information to be propagated at a good speed, we don't want DNS servers to be bogged down.
- If we start using DNS servers to send information larger than the usual DNS information, we bog them down.
That isn't to say that I think BitTorrent cacheing isn't possible. I just don't think it's a good idea to use existing DNS servers for it, although perhaps something could be built on similar technology, or dedicated Torrent users could run their own DNS servers if they're that determined to do something so bandwidth-intensive..."It is dark. You are likely to be eaten by a grue." -- Zork
I don't think it is a bad idea but I think we must start making "prime directives" ala RoboCop. ....
Prime Directives
1. Get DSL/Cable Modem
2. Install Linux/BSD/OpenSource OS.
3. Do not mess with DNS
would be fun if one could download torrents from riaa, mpaa and whatever those ....... are called
Some of us have been using DNS to get through some really draconian firewalls for ages. It was just a matter of time before we saw someone distribute files this way. What is unique is that they will be cached. This in and of itself is an amazing idea. DNS is well designed to cache for well defined amounts of time.
The load on large DNS servers can grow quickly. I wouldn't be surprised if we see a set of patches coming out for DNS servers to combat this. the question is can we find a TTL that reduces the abuse and still makes it useful.
It's cool hack not withstanding how useless it is. I suppose if you were on a closed network that needed to propagate a lot of torrent files for some reason it would make since, but still it's a cool hack.
BitTorrent already requires fixed servers for operation (the "trackers"), and serving torrent files from the same trackers isn't a terrible burden. Why on earth would someone want to abuse DNS for this purpose?
Yesterday night when i could not sleep i thought of what fun i could do with one of the most
distributed database in the world. The DNS!
yeah its fun fucking up the DNS for everyone, haha i laugh everytime a virus wipes out half the net or your hardrive, its fun ruining other peoples stuff, its cheap like you say right ?
Freenet over DHCP;
Gnutella over BOOTP;
And last, but not least, KaZaa over WINS!!! :)
You are not the customer.
It's actually a proof of concept of DNS where its been reprogrammed to send BitTorrent files, not the other way around.
Let's use the rpc protocol for ftp transfers! This sounds like it could be fun!
Why would anyone want to "combat" it?
Also, if you'd bothered to read the article (all one page of it) you'd have seen:
Sounds pretty much like putting it into the required format, doesn't it?
Meep meep
DNS is being used to exchange the Torrent files, which are small, not the data itself, which is large.
The Torrent files are indexes that tell your BitTorrent program where and how to get its data.
This sounds very useful, since what was missing from the BitTorrent network was a way of distributing cached Torrent files, and this is exactly what DNS provides.
Remains to be seen whether it actually works, but it's a neat concept.
Ceci n'est pas une signature
If you read the article and know anything about DNS, you can see that he is splitting the file into 126 byte segments and storing the parts in TXT records of individual hosts. The host naming scheme is quite clever, I might add.
The goal is to offload the duty of serving up the files from the download servers to an existing distributed network. He even mentions that the DNS servers caching these records would consume massive amounts of memory, and then (like a spammer) blows it off as "its [memory] not that expensive today anyway."
If this is actually implemented on a wide scale, DNS administrators will simply stop caching TXT records, putting the load right back on the original download server where it belongs. Or worse, they may stop caching records altogether, which could only lead us all down the path of chaos, death and destruction.
I agree that it's clever, but like a deadly virus, not something that should leave the lab on a large scale.
Why don't we funnel all trucking traffic into and out of all major port cities through residential streets!
That way, a system we already have in place that seems to work ok can be scrapped, and we can bog down commuters only BLOCKS from their homes!!!!
THEN, I can get my article on Slashdot.
I am become Troll, destroyer of threads
news doesn't exist to just publish the good ideas, unless you really /want/ censorship
He's just talking about the .torrent file, which points to a torrent tracker, not the torrent data itself; and DNS works over TCP also.
Using DNS to cache a dozen or two kilobytes (or less, or more) where it's only meant to handle a few BYTES is likely to cause all sorts of problems.
but ed2k:// URLs...? These are maybe 200 bytes long...
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
True, but 0_197_56633ab0d90f43c68ed1b47358eccfe7.domain.com is (as far as I know) not a real domain.
And admins would want to combat it to prevent "DNSservers will use a loooot of memory" and "bog down BIND servers all over the planet" as the article says.
Except FTP is for Server \ Client tranfers
BitTorrent is for splitting up the load between many machines. ( aka P2P )
Browse at -1, because trolls are often the most creative part of
There are already a number of posts on Slashdot talking about how this is a really bad idea. I disagree (with a big but). It would almost certainly be a Bad Idea (TM) if this were enacted and people tried to make it the main way of distributing torrents. However, I don't think the idea was meant to do that, I think it was more just to show that it could be done. It's akin to people who get put on the mainpage of Slashdot for hacking their Apple IIe's so that they have ethernet and then writing a simple graphical operating system for them so they can browse the web. Impractical and largely useless? Probably. Interesting and fun hack? Definitely.
If people start using this extensively, and the DNS servers start getting clogged up by this, we'll just have to come up with a way to send DNS information over BitTorrent! That way, everything will balance out, right?
If someone adds TXT records to their dnses and in turn to their dns slaves it's their buissnies, how the hell will this affect all dnses available in the world? You generally ask the "owner dns" but yes, if you ask your "ips's dns" or someone elses dns then they might cache the result.
.torrent file? And wouldn't linux distrobutiors enjoy this?
/me is also a typical Swedish geek =)
But how bad is that really? How large is a
$large_isp has several users who wants to download $linux_dist. The first user gets the TXT record and is off downloading. And the rest of em uses the cached record (if it is cached) in either case $linux_dist's webserver dosn't suffer as hard and they can always add more slave dnses to handle the load. Perhaps users even starts slave servers for that zone to help the dist.
(Is there really a rule that says "you have to cache and store TXT for $TTL time".)
And whats this with spelling? I mean you totally miss the point and... complain about spelling? is that the end of the world? =)
DNS is a resource locating service. For example, SRV records are a nicer way of autoconfiging your network.
With SRV records, you say service.domain = port at host. You could do a dig for ldap.slashdot.org and findout that the ldap server is on port 389 at directory.slashdot.org.
This is a slight extension of this. I don't know the exact implementation, but you could have a zone file that looks like:
'file being served'.bt.slashdot.org SRV 0 0 PORT 'seed host'
You can have multiple SRV's per resource and load balance between them.
DNS is currently used for stuff like this all over the place. We already have the technology. IXFR means we can transfer just the changes in the zones when there are updates.
Last time I checked, DNS is not over loaded and will scale to handle this. Even it 50% of the internet uses BT over DNS, 100% of the internet uses DNS for email, web and so forth. Every time an email is delivered, there are at least 6-10 DNS queries.
DNS will not be bogged down.
-- DrZaius - Minister of Sciences and Protector of the Faith
The tracker does not allocate bandwidth, it just introduces peers to each other.
Bloody well put mate, lets hope the mods get this rated up before everyone else miss's it.
moo
/. stripped out my "less than" sign.
I would guess that serving .torrent files is not a problem compared to the bandwidth and CPU used by the tracker. When downloading a file via BitTorrent, you only download the .torrent once but you check in with the tracker every few minutes.
I've been wondering about (ab)using DNS for FreeBSD Update -- the idea being that when you're updating a system which is not up to date with security fixes, you might want to be behind a draconian firewall. (The caching benefits of DNS are a non-issue; updating a year-old RELEASE takes only a couple MB.)
In the end, I decided that it would be more trouble than it's worth; but if someone else has written code I can borrow (I haven't looked in detail) then I might reconsider this.
Tarsnap: Online backups for the truly paranoid
Often, slashdotted articles are still available thru Google. That might work.
Why would anyone want to "combat" it?
Why would anyone not?
If Google really cared they would fix Android Chrome to reflow text, instead of discriminating
From what I can tell he is merely talking about the data that says where the main download data (i.e. the iso or whatever) is. Kind of like storing a mirror list in the TXT record.
So the ftp thing would not be an accurate comparison.
My Suburban burns less gasoline than your Prius.
Of course DNS data has a required format (the actual files used to configure it depend on the implementation, but not the data sent over the wire). And this format is extensible to transport arbitrary kinds of data, totally unthought of when the protocol was fixed. DNS already gets used for all kinds of funky things that haven't much to do with domain names.
Programming can be fun again. Film at 11.
From TFA: "due the nature of the DNS it *CACHES* the entries"
No, that's BIND. And a BIND zonefile is just that: a BIND zonefile. All this is about BIND, not DNS. It does not work "over" or "with" or "through" DNS.
It's not clever either. More like abusing other people's resources.
Less is more !
I discovered this the other day,
http://www.torrentsearch.org/
basically its a p2p program that downloads the whole database of
You can then search for torrents through the gui. You can then download the
nick
Electronic Music Made Using Linux http://soundcloud.com/polyp
I guess one could sarcastically say thanks for the proof of concept, real good job. But then again, its better they did it and let everyone know it could be done, rather than having to find out about it 'in the wild'. I just hope its easy to prevent.
Manipulate the moderator system! Mod someone as "overrated" today.
$ dig txt 0_1197_56633ab0d90f43c68ed1b47358eccfe7.netrogenic .com
c .com
7 .netrogenic.com. IN TXT
. netrogenic.com. 3118 IN TXT "64383a616e6e6f756e636534333a687474703a2f2f746f727 2656e742e64756c75672e64756b652e6564753a363936392f6 16e6e6f756e636531333a6372656174696f6e2064617465693 130363830353734393265343a696e666f64353a66696c65736 c64363a6c656e6774686935373565343a706174686c363a4d4 435"
; <<>> DiG 9.2.1 <<>> txt 0_1197_56633ab0d90f43c68ed1b47358eccfe7.netrogeni
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51320
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;0_1197_56633ab0d90f43c68ed1b47358eccfe
;; ANSWER SECTION:
0_1197_56633ab0d90f43c68ed1b47358eccfe7
;; Query time: 3 msec
;; SERVER: xxx.xxx.xxx.xxx#53(xxx.xxx.xxx.xxx)
;; WHEN: Sun Nov 30 13:13:56 2003
;; MSG SIZE rcvd: 337
Since people are serving data over DNS...
Why not server domain name information over HTTP?
See, I told you DNS would cause problems
;-)
You should have listened to me and stuck with Host files
bittorrent is not your regular p2p. read up on how it works and report back later.
Its design supports more networking addressing schemes than TCP/IP. These Bittorrent files are just addresses one/two abstraction levels from raw ip addresses. No big deal. You all sound like a bunch of whiney old ladies. Death of DNS! News at 11! The impact this will have on the DNS system you couldn't even measure with an electron microscope so just calm down.
looks to me like the rootservers themselves would have nothing to do with it. Where it hurts is the ISP's nameservers which have to cache the stuff. When I to a TXT lookup on some domain all the root servers do is point me to the right server to awnswer that request (or one that might know the one that knows the awnswer) Suprnova.org gets 1million+ hits per day iirc, so a few extra million hits per day to the rootserver is negligable. Infact if all of the queries were to somthing like 0_197_56633ab0d90f43c68ed1b47358eccfe7.suprnova.or g then the isp's servers would cache the nameserver for suprnova.org, so it would result in virtualy no increased load on the root servers.
Alan
Lots of postings discuss the load being placed on the DNS servers as lots of mp3's and binaries are transferred through them. Perhaps I am misunderstanding this but surely it's just the .torrent files themselves that are being distributed. The torrent files are just pointers to the trackers which keep a record of the peers who have the files. Distributing the .torrent files probably wouldn't put a massive load on DNS Servers.
The Romans didn't find algebra very challenging, because X was always 10
For most torrent sites, the slowness comes from the webserver being used as the tracker. This is not true of SuprNova, as it has many mirrors. I personally have not had trouble with most SuprNova mirrors myself, though I imagine there are probably some poor mirrors out there hosting the files.
because what hunting rifle has a bayonet lug
Or even an exit criterion.
man...i laughed my ass off at that one, imagine all the broadcast traffic. You'd DDOS the entire internet.
And he's coded what is obviously the *worst idea ever!*
Does he work for Verisign?
newsgroups are by far the Biggest distributed file servers and are cached at the ISP level. Why not make a bittorrent client that will hook up to your local Newsgroup server and download the file? (sure not all ISPs have all the newsgroups but the good ones have allot)
Why not use another p2p application like kazaa to host the torrents.
...how do you get the torrent file on to the DNS? Is there some magical request that you send it in order to get your torrent chunks on to a DNS server?
.torrent files could be distributed via XDCCs and P2P programs.
Also,
Yeah, your average .torrent file is about 15K (according to my OLDTORRENTS dir), so that's a lot of segments, a lot of bandwidth, and a lot more memory required to cache thousands upon thousands of torrents.
DNS administrators will simply stop caching TXT records
It's more likely they'd patch their DNS servers to filter out only the suspect non-text TXT records, which means the torrents would have their SHA1 hashes dropped and would be useless.
d8:announce36:http://tsazz.sytes.net:6969/announce 13:creation datei1069918597e4:infod6:lengthi366858240e4:name32 :enterprise.311.hdtv-lol.[BT].avi12:piece lengthi1048576e6:pieces7000:***HASH SNIPPED***
--
Power to the Peaceful
But if you make torrents of the torrent files it would be feasible:
ranma@melchior:~$ ls -l test.torrent
-rw-r--r-- 1 ranma users 111443 003-11-30 21:58 test.torrent
ranma@melchior:~$ ls -l test.torrent.torrent
-rw-r--r-- 1 ranma users 171 003-11-30 21:58 test.torrent.torrent
Now if it were possible to specify multiple trackers in one torrent, it would be even better, because even if one were offline the others could be used.
Tobias
http://security.royans.net/info/articles/dnsinfohi ding/
This is a quote from the man page for named.conf on solaris.
Sounds like a neat program. Unfortunately, it sounds like a festering mound of virus that would singlehandedly OWN any machine it touches and any unfortunate user too impatient or stupid not to click "AGREE: Totally Hose My Machine". I'm quoting the EULA here, not making this stuff up. Gator's spyware is green with envy:
By accepting this agreement, I certify the following:
4) I understand that by accepting these terms and conditions, this program will be installed on my computer and my web browser home and search page will be changed in order to allow me access.
5) I also acknowledge that a Desktop toolbar will be installed on this system as a stand-alone module and that the Desktop toolbar will update itself from time to time in accordance with the EULA Privacy Policy.
6) I further understand that an accessory tool bar will be added to my web browser which will remain visible as long as the software is installed and agree that I wish to use your search engine for my
web browsers auto search option and default error age.
7) To insure you always have the latest version and for your convenience this software will automatically update itself from time to
time once installed in accordance with this EULA and Privacy Policy.
8) If you decide to change your homepage or search page at a later date this information ?the url? will be sent back to our servers and a pass-through toolbar will be installed at the bottom of your web
browser. This toolbar will remain active as long as this software is installed on your system.
9) I understand that, by accepting these terms and conditions, bookmarks will be added to my system, which may be removed manually or via un-installation of the software.
10) In order for us to keep this software free, from time to time promotional offers from our sponsors will be displayed to you.
11) To prevent your browser from becoming cluttered when our toolbar is installed, any other toolbars you currently have visible will
be deactivated. They can be restored manually through the IE view menu.
12) In order for this software to function properly, If incorrect host-file entries are detected for this software's related domain
names, those entries will be removed.
13) If you wish to uninstall this software you may do so at any time by going to your start menu, Control Panel, Add / Remove Programs, and then selecting this application. Additionally a separate uninstaller may be downloaded from the website the Sponsor Software installs
in your web browser, or you mail email support@lop.com for further assistance.
14) Bookmarking to a page on this server/site whereby this warning page is by-passed shall constitute an implicit acceptance of the
foregoing terms herein set forth.
And it does go on.
Umm, if the point is to reduce http traffic, I think the obvious solution should be a caching proxy server. Your ISP should already have one. I admit the story was fun, and it must have been great to hack on it, but it's not really about caching.
Escher was the first MC and Giger invented the HR department.
Ha! I'd love to see the Australian ISPs block DNS. Suck that.
Karma: It's all a bunch of tree-huggin' hippy crap!
I love the US patent system.
Second, criteria is often used as a sigular form when it means compound criteria, or a logical expression with other criterions.
Either way, it's usually aceptable to say an exit criteria, as well as just exit criteria.
Less is more !
I thought I'd better check what you said, given that it sounded wrong. So I did. And it would appear that criterion is the singular, criteria (less commonly criterions) is the plural, but that criteria is not acceptable in the singular. So the phrase "an exit criteria" is wrong.
It's more likely they'd patch their DNS servers to filter out only the suspect non-text TXT records
Why would administrators care? The same data is going to come down over either HTTP or DNS. There's nothing inherently more expensive about passing it through bind rather than squid. The point of ISPs is, after all, to provide internet service.
a lot more memory required to cache thousands upon thousands of torrents.
You only need to cache them if your users are actively downloading thousands upon thousands of files. If you're really doing terrabytes (3000 x 660MB) of traffic per day, I think you can afford a big DNS server or two.
Unless the point is to stop people using BitTorrent altogether -- I suppose you might want to do that in a business environment, but in that case you've probably blocked the ports already.
Just ensure that the DNS checks to see that the new file is actually a legal DNS zone file. I assume these things have a required format?
Why would anyone want to "combat" it?
Remember, the RIAA/MPAA have lumped BitTorrent in with KaZaa and other P2P music services in its "war on piracy". Various people have counter-argued (correctly) that unlike those other services, BitTorrent is really just a protocol (like FTP, only peer-to-peer). The lack of any kind of built-in search functionality in BitTorrent is the clearest example of this, the example most obvious to non-technical types.
Now, what would happen if someone created a type of BitTorrent search? Perhaps nothing, especially as long as people are just making Linux ISOs and the like available. But what would happen if people started making ripped mp3s or movies available in large numbers? The RIAA/MPAA would presumably try to shut them down, right? Go after their servers, or their search software, or whatever. Okay, here's the 64K question... what happens if that search functionality uses the DNS protocol and DNS servers and the entire Internet relies on those protocols/servers? Things could get interesting!
FYI, as someone who designs systems for a large-ish ISP, I would rather people get their linux distro from our mirror server. .torrent just cannot match the serving power for our customer base, and certainly not the economics.
.torrent tracker data in the DNS servers. It'll be interesting to see the result.
The fetching of linux distro ISO's is often used to justify BT, but the author's own notes point to suprnova, which has trackers to very little content that is licensed for free re/distribution.
And yes, the mirror is big and powerful, and has all major linux and *bsd's, with some minor ones too.
Nevertheless, I'll now keep an eye for
Of course, you're right, even if you didn't realize why -- underscores are illegal in domain names.
- Michael T. Babcock (Yes, I blog)
I don't see what the issue is, exactly. DNS data is propagated lazily. The only issues is that you'd have maybe three machines storing the data instead of one.
.torrent files are particularly big -- I happened to have one on my hard drive, which was under 512 bytes.
.torrent files -- it seems that USENET or similar would be a better choice, given that they tend to only be useful for a short period of time, that announcements of new torrents is a useful characteristic of a .torrent propagation system, and that archiving torrents is useful -- but I also don't really see the harm in this.
.torrent file, the bandwidth will not be an issue.
Unless
I'm not sure that there's much point in using DNS to propagate
Given the kind of load that nameservers happily handle today when you hit a webpage with a number of entries (especially for those annoying little "badges") (and the nameserver potentially gets twenty or more lookup requests all at once), there can't be a huge processing hit.
There *might* be a storage hit...but suppose there are 10,000 torrent files out there, and each is 1K. That's just 10MB of data, and I doubt anyone is interested in storing all available torrents.
Finally, I suppose that bandwidth might be an issue, but I suspect that given the frequency of DNS lookups and the infrequency of someone needing a new
I have done plenty of fun things with DNS and run a small DNS server, but I will freely admit that I am not a DNS wizard, and leave it to the folks on NANOG to debate the merits of this.
For my money, though, this is cute and not harmful at all, though it might not be particularly useful.
May we never see th
Suprnova.org gets 1million+ hits per day iirc
That'd be clever, since it was shut down months ago...
There's just a generic 'No access' page there now.
Better check webster.com - first, it's free, second it's a pretty reliable source. and it says:
The plural criteria has been used as a singular for nearly half a century
You may want to looak at google how many pretty "oficial" documents use a single criteria.
Finally, check "CiteSeer" (very "academic" computer-science article repository) for a single criteria.
I understand you attempt to keep English clean, but there is not such thing as a standard English. It's a very alive social phenomenon, varying over the time and across social groups.
And your attempt is especially loughable at /. :)
Less is more !
These beasts are different from root servers (although many of the same entities run them). Many ISPs run one or more levels of caching DNS servers to reduce load and latency. This is where most of the caching would occur.
Torrentsearch installs a LOT of spyware (more than it admits) - I recommend running it on a PTP bitch box rather than your regular machine.
How about something that would propagate and self refer via googles cache? (Or something like that) .torrent files are usually 80K, so were not talking even remotely a slashdot hit here.
It might work, assuming google mines its own cache... might be a public service or hell, don't know.
The real question is will some one else come up with something else built on the concept? Will it lead to a revolution in DNS system? Or perhaps a new version of Freenet? a new IM project? Perhaps some one will turn the concept into an application-directory-service, one where 500 different distributed apps use it for various things. Or perhaps someone else will look at this and see another new use for some other tried and true tech.
The point is not always that something should be done, but that a potential value exists in a unique idea (or in this case, an extension to an old idea), and should be given a closer look by the community at large.
1. An ugly, ugly hack, and a wrong tool for the job (tm)
2. Wrong using others' resources in a way that is not intended (serving binary data)
My goal of using the DNS is however the same: solve the dead trackers problem. But to serve data directly from DNS, my idea to use what DNS is for: route traffic. You request the torrent's 40 byte info_hash as a subdomain of the DNS server's domain, and it returns you the optimal tracker's IP. For example:
{torrent_hash}.bthub.com
and bthub.com will be where i'll host the DNS service. It's basically a dynamic DNS server, updated frequently, of all known torrent hashes from different trackers in its database (my estimation is around 15000 - 20000 torrents, or subdomains. I know because I run a BT search engine, see my sig). This way, you don't "hack" the DNS, but you get the benefit of:
1. Dynamic routing to the tracker with the most ppl downloading your file, or the biggest "swarm", and hence the highest speed
2. Re-routing to a SINGLE new tracker when one dies
The 2nd benefit is important, as the case today is ppl just randomly pick a new tracker when the original dies, without knowing how big the swarm is on the new tracker. This splits the original torrent swarm across multiple trackers, which don't talk with each other (yet).
There are some discussion on the mail list of adding connectivity between the trackers, similar to how you link IRC servers together into a network. But that's no where near a proposal, and using DNS to act as a "hub" for the trackers would need the least effort and changes to the BT protocol and trackers.
I discussed this idea in detail on this thread "Decentralizing trackers: Use hubs", feel free to take a look.
VIVA1023.com | Political Fashion.
Sir,
I'm actually not too sure what bothers you so much about this. DNS servers are, overall, very smart beasts. They know how much memory they're allowed to consume, and drop records from their cache to stay within their limits, based on certain criteria -- primarily 1. the frequency they are requested and 2. Their TTL value (pull-date).
If a record isn't getting requested very often, it is more likely to drop out of cache. A few hundred extra bytes in one record may make another record more likely to fall off the cache earlier -- but that record would most likely have been infrequently accessed and stale verging on expired.
If the entries associated with a torrent aren't requested very often then they'll get bumped down and drop off too. If they are requested, then it's legit: DNS is connecting clients with servers like it is supposed to, and all's right in the world.
Or am I missing something?
I want a new world. I think this one is broken.
BT polls the tracker asking for peers. Compare it to the era of reverse-engineered napster: you've got lots of clients connected to one (of many) napster clones, none of them talking to each other.
If BT's one redeeming feature (swarming downloads with economic model of tit-for-tat) was put into a real P2P app you would see a massive increase in filesharing. In the end, as long as you know a valid info_hash, you know you're getting the right file.
This shouldn't be surprising to anyone. DNS can store any sort of data. It's just a system for distributing keys and values...
"he drew his sword Ringil that glittered like ice... and he wounded Morgoth with seven wounds..."