FEB 28th 2007

MetalinkMetalink was designed for describing the locations of large files that are multi-located (shared via many mirrors and with P2P) to increase usability, reliability, speed, and availability. If a server goes down during a download, download programs can automatically switch to another mirror. Or segments can be downloaded from different places at the same time, automatically, which can make downloads much faster.

Besides location, it also describes content. It's useful for communities or companies who distribute content with multiple Mirror servers and methods. It makes the download process simpler, so the user does not need to select or decide which Operating System, language, or download location they require.

Noteworthy features:

  • Standard format for listing multiple mirrors for redundancy and/or automatic accelerated (segmented) downloads.
  • Combines FTP and HTTP with Peer-to-peer (P2P, shared bandwidth).
  • Simplifies advanced download features, layout, and user experience.
  • Automatic checksum verification; No separate MD5/SHA-1 file or manual process for integrity verification.
  • Automatic error recovery and repair of corrupted downloads.
  • No Single Point of Failure (SPOF) like FTP or HTTP URLs. More fault tolerant.
  • Stores more descriptive and useful information for software distribution.
  • Backward compatible with regular hyperlinks.
  • Automatic load balancing distributes traffic so individual servers are under less strain.
  • No long confusing list of possibly outdated Mirrors and P2P links.
  • Automatic generation, editing, and validating is easy with standard text processing tools.
  • Makes the download process simpler for users (automatic selection of language, Operating System, location, etc).
  • Uniquely identifies files, so even if all references to it in the Metalink stop working, the same exact file can be found in other places.
  • Share a library of files between file sharing applications with a small .metalink.
  • Can finish P2P downloads even if files are no longer shared.
  • For FTP/HTTP, an updated client is needed, but not a separate client like some types of P2P.
  • No changes or separate services needed on the server side, like a "tracker" etc.
  • Useful for automatic updating programs when new versions are released.

Perhaps one of the most interesting thing about Metalink is that aside from storing server information in its XML-based .metalink format, metadata such as the location of the server, document tags, and license of the file are also stored.

About the author

James Simmons

It's my goal to help bring about the Semantic Web. I also like to explore related topics like natural language processing, information retrieval, and web evolution. I'm the primary author of Semantic Focus and I'm currently working on several Semantic Web projects.

Trackback URL for this entry:

http://www.semanticfocus.com/blog/tr/id/281981/

Spam protection by Akismet

Comments for this entry:

No one has left a comment for this entry. Be the first!

Post a comment

  1. Spam protection by Akismet