Categories
Computing Video

Broadcasting without a broadcast network

Hosting video (or any large file) on a webserver has a problem – when a moderately large number of clients want to download it simultaneously the overhead of each individual connection can overwhelm the server. The number of people that can be serviced is quite likely to be lower than the audience for any popular file, and waiting an unpredictable time for the server to become free is a frustrating experience for the viewer.

There are several possible solutions to this:

  • Multicast IP
  • Hosting on multiple servers via Mirroring or a Content Delivery Network (CDN)
  • Collaborative (peer-to-peer) downloading

Multicast IP allows the server to share a connection among many clients, but for various reasons is not available on the public internet so needs to be discounted. Hosting on multiple servers is straightforward, but is costly and out of reach of individual authors.

Collaborative downloading allows the author to require each viewer to also act as a server for that file. In this way an ad-hoc multiple server system can be created, with costs split between the author and each viewer. Whether your viewers will be happy with this probably depends on what you charge them, and what they get in return. Most pay-per-month internet connections allow them to make a useful server contribution at no direct financial cost to them.

A popular collaborative download protocol is BitTorrent, which is included in Miro. An author distributing video to Miro (or similar) viewers can therefore choose whether to deploy multiple servers, or rely on viewers to collaborate as downloads occur. The ability to broadcast without investing in a network of servers should make it materially easier to distribute video from small providers on the internet, in a similar way that blogging has brought publishing words within an individuals reach.