Re: Expect: 100-continue and proxies

Just an FYI: before anyone fiddles with the Expect/Continue
mechanism, you should definitely read this paper:

  @INPROCEEDINGS{Bradley02safecomposition,
      author = {Adam D. Bradley and Azer Bestavros and Assaf J. Kfoury},
      title = {Safe Composition of Web Communication Protocols for Extensible
       Edge Services},
      booktitle = {In Workshop on Web Caching and Content Delivery (WCW},
      year = {2002}
  }

  Available via:
  http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.9.2854

The title is a bit of a red herring; the paper is mostly about
the specific case of the Expect/Continue mechanism.  In particular,
very subtle issues can create deadlocks when trying to interoperate
between proxies, clients, and servers implementing slightly different
versions of Expect/Continue.

I wouldn't expect the working group to use the same formal-verification
techniques that these authors used (not that it would be a bad idea
to do so, just that I don't think it will happen), but at least
people should try to understand the causes of the problems exposed
by this paper, before changing anything here.

-Jeff

Received on Monday, 22 February 2010 22:52:48 UTC