$ WWW95: WWW media distribution via hopwise reliable multicast

WWW95: WWW media distribution via hopwise reliable multicast


  1. abstracts
  2. repeated access to WWW pages currently makes inefficient use of the available network bandwidth. a distribution point model is proposed where large and relatively static sets of pages (e.g. magazines) are distributed via bulk multicast to LAN distribution points for local access.
    Hopwise Reliable Multicast (HRM) is proposed to simplify reliable multicast of non-real time bulk data between LANs.

  3. my comment
  4. james e. donnelley from the lawrence livermore national laboratory, livermore, USA explained how nowadays the network bandwidth of the Internet is wasted by repeated access to the same WWW documents. while it is necessary to access dynamic pages on the original server, static documents like on-line magazines, newspapers a.s.o could be distributed to locations closer to the client. caching is one mechanism to address such a problem, but introduces new difficulties like cache notification and it does not improve the access time for the first access. another approach to this problem is the so called distribution point model, where the data is distributed before it is accessed.

    james e. donnelley proposed a hopwise reliable multicast (HRM) similar to the Internet MBone. but while MBone is a real time multicast distribution service where information may get lost without disturbing the service to much, HRM is intended for non-real time bulk data distribution. HRM would be based on a reliable transport protocol such as TCP. the daemons involved in the data transmission would be clever enough not to distribute data over the same datalink twice. if the data does not arrive at its final destination, it would be re-transmitted, either to an individual host or again by using HRM.

    to me, the proposed HRM looks like a very interesting alternative to caching algorithms to reduce Internet network traffic. the idea of distributing data to distribution point while the network traffic is relatively low and - even more important - before the data is requested by the user, seems very appealing. at the same time, it solves the problem of cache notification of obsolete pages.


this paper is available on the Web.
back to WWW95 main document

WWW_media_distr_hopwise / 19-apr-95 (ra) / reto ambühler