Browse Prior Art Database

Method for Web Browser to Project Download Times and Adjust Behavior Accordingly

IP.com Disclosure Number: IPCOM000119080D
Original Publication Date: 1997-Nov-01
Included in the Prior Art Database: 2005-Apr-01
Document File: 2 page(s) / 104K

Publishing Venue

IBM

Related People

Furminger, JP: AUTHOR [+3]

Abstract

Disclosed is a method to allow a web browser to predict download times of page embellishments (images, JAVA applets, etc.) and adjust its requests accordingly. Based on the projected download times, the browser can choose among loading an image, loading an alternate image, or omitting the image from the displayed page. By making this choice, the browser can adjust its behavior to network conditions. And, by avoiding requests for files that will take so long to download that the user cancels the request, network congestion will be reduced.

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Method for Web Browser to Project Download Times and Adjust Behavior
Accordingly

      Disclosed is a method to allow a web browser to predict
download times of page embellishments (images, JAVA applets, etc.)
and adjust its requests accordingly.  Based on the projected download
times, the browser can choose among loading an image, loading an
alternate image, or omitting the image from the displayed page.  By
making this choice, the browser can adjust its behavior to network
conditions. And,  by avoiding requests for files that will take so
long to download that  the user cancels the request, network
congestion will be reduced.

      Data is typically compressed for transmission using some
lossless compression scheme.  This is ordinarily done by modems, for
example.  The compressability of a file depends on the complexity of
the data it contains.  It varies with the particular compression
scheme used too, but generally not too much among modern compression
schemes in common use.  We need to allow for this compression in
predicting file transfer times - a large, sparse file may download
quicker than a much smaller, complex file because the compression is
so much more effective for the sparse file.

      Simple additions are made to the HTML, formatting a web page to
allow the browser to predict download times.  The file to which we
are making these additions will be referred to as the "base page" to
distinguish it from other pages, images, etc., referenced within this
base page.  Using some compression scheme roughly equivalent to those
expected to be used in moving web files across slower parts of the
network, determine the compressed size of the base page and all
referenced images.  Then calculate the ratio of each compressed image
size to the compressed size of the base page, and add this
information to the HTML tag referencing the image.  For example, a
typical image tag:
  < img src = "/masthead/vmmast.gif"height = "72" width = "600"
  alt = "IBM*'s VM operating system">
  would have a "size" parameter added to give
  <img src = "/masthead/vmmast.gif" size = "42" height = "72"
  width = "600" alt = "IBM's VM operating system">

      The  size = "42" parameter would mean that the compressed image
size is 42 times the compressed size of the base page.  The browser
can then project that it will take 42 times as long to download.  The
base page has already been downloaded, and the browser can have timed
it and, therefore, can project how long downloading the image will
take.  Actual download times will vary, depending on network
congestion in particular.  But, conditions are likely to be very
similar for transmitting both files, so the ratio is likely to remain
accur...