# DistribuStream **URL:** \ **Category:** ruby-talk\ **Created:** [31 October 2007 21:39 UTC](https://rubytalk.org/t/distribustream/41825 "2007-10-31T21:39:30Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Tony\_Arcieri5](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Tony\_Arcieri5](https://rubytalk.org/u/Tony_Arcieri5)\ **Post date:** [31 October 2007 21:39 UTC](https://rubytalk.org/t/distribustream/41825/1 "2007-10-31T21:39:30Z")
DistribuStream is an open peer-to-peer communications system which aims to become the successor to BitTorrent. You can read about it at [http://distribustream.org](http://distribustream.org) Unlike BitTorrent, DistribuStream facilitates streaming progressive downloads, making it an open alternative to proprietary protocols like Joost. DistribuStream is written on top of the Ruby/EventMachine library which, at least on Linux, allows it to scale to thousands of concurrent connections. It was developed collaboratively by ClickCaster, Inc. and the University of Colorado Computer Science program. The underlying protocol (Peer Distributed Transfer Protocol or PDTP) has received an IANA port assignment of 6086. All source code is available under the GNU General Public License v3. We don't plan a Ruby-licensed version at this time, sorry. The protocol is philosophically different from BitTorrent, which relies on emergent, swarm-like behavior for traffic scheduling. All client/server and peer-to-peer communications can be modeled as simple state machines. The onus of traffic scheduling is placed entirely on the server. Client/server communication is accomplished with a lightweight JSON asynchronous messaging format (presently running over TCP). Peer-to-peer communication is accomplished with HTTP/1.1 using the Mongrel HTTP server. The entire protocol behaves as an ad hoc HTTP caching proxy network. If you'd like to check it out, it's available as a RubyGem: gem install distribustream Check out the README file for help getting started: [http://distribustream.rubyforge.org/svn/trunk/README](http://distribustream.rubyforge.org/svn/trunk/README) An example configuration file is available here: [http://distribustream.rubyforge.org/svn/trunk/conf/example.yml](http://distribustream.rubyforge.org/svn/trunk/conf/example.yml) Enjoy! > **···** > > -- > Tony Arcieri > ClickCaster, Inc. > [tony@clickcaster.com](mailto:tony@clickcaster.com) ---
**Author:** ![Joel\_VanderWerf1](https://avatars.discourse-cdn.com/v4/letter/j/94ad74/32.png) [@Joel\_VanderWerf1](https://rubytalk.org/u/Joel_VanderWerf1)\ **Post date:** [1 November 2007 01:21 UTC](https://rubytalk.org/t/distribustream/41825/2 "2007-11-01T01:21:56Z")
Tony Arcieri wrote: > DistribuStream is an open peer-to-peer communications system which aims to > become the successor to BitTorrent. I'm quite interested in the "ad hoc HTTP caching proxy network" part. Some of the folks I work with in the CE dept at Berkeley want to use HTTP for services in ad hoc vehicle networks (VANET). In another project, I'm using ruby for HTTP proxying over mobile wireless networks using UDP broadcast on the wireless link (DSRC), instead of TCP, to avoid the setup time. Caching is valuable because the networks are so limited in bandwidth, latency, and connection duration. However: there's gotta be a better name than DistribuStream. Why call it "distribu" stream if its main difference from BitTorrent is that it is more centralized? ("The onus of traffic scheduling is placed entirely on the server." Isn't that going to be a bottleneck, anyway? Or can the servers be distributed? How do they cooperate?) If you'll forgive the suggestions, what about...? Distributary (a branching river) Bitstributary Roost (like Joost, but "R" for ruby) Distribrew Brew Brewst Ignore the last few. I'm probably just feeling bad about not drinking beer with all the great ruby minds. Thanks for announcing this. > **···** > > -- >        vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407 ---
**Author:** ![Tony\_Arcieri5](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Tony\_Arcieri5](https://rubytalk.org/u/Tony_Arcieri5)\ **Post date:** [1 November 2007 02:54 UTC](https://rubytalk.org/t/distribustream/41825/3 "2007-11-01T02:54:59Z")
> I'm quite interested in the "ad hoc HTTP caching proxy network" part. > Some of the folks I work with in the CE dept at Berkeley want to use > HTTP for services in ad hoc vehicle networks (VANET). In another > project, I'm using ruby for HTTP proxying over mobile wireless networks It doesn't provide a caching HTTP proxy network in the traditional sense. The protocol works by the server directing clients to perform successive HTTP GET and PUT requests to assigned peers, with each peer running a local HTTP server and authenticating traffic against the central server. It effectively provides a little botnet you can use for the purposes of HTTP caching and control the way you see fit. If you wanted to use it to set up a mini-CDN on a wireless network, the protocol would facilitate it but the current implementation currently isn't set up to do that. With a little hacking it'd be pretty easy to do... using UDP broadcast on the wireless link (DSRC), instead of TCP, to > avoid the setup time. Caching is valuable because the networks are so > limited in bandwidth, latency, and connection duration. The plan is to go UDP, because overall it'd be a big win for improving latency and lowering overhead, like you expressed. The entire protocol can be modeled as state machines to begin with so it's not hard to add timeouts/retries and ditch TCP altogether. There are no particularly large datagrams in the entire protocol, not do the size of the packets scale with the size of the data being transferred or anything like that. However: there's gotta be a better name than DistribuStream. Why call it > "distribu" stream if its main difference from BitTorrent is that it is > more centralized? Haha, BitTorrent wasn't really a consideration when we chose that name. While the transfer control is centralized, the purpose is to provide distributed content streaming across a peer network. "The onus of traffic scheduling is placed entirely on > the server." Isn't that going to be a bottleneck, anyway? Or can the > servers be distributed? How do they cooperate? It won't provide any more of a bottleneck than BitTorrent trackers now in terms of bandwidth, and due to the way the protocol is designed messaging between "peer" and "tracker" will have substantially lower overhead. If there's a bottleneck it's going to be an algorithmic one in the server's network regulation. There's no clustering now, although that could easily be added with DRb. If you'll forgive the suggestions, what about...? > I don't think we'll be changing the name at this point, sorry... 🙂 > **···** > > On 10/31/07, Joel VanderWerf \ wrote: > > -- > Tony Arcieri > ClickCaster, Inc. > tony@clickcaster.com