Re: holding connections open: a modest proposal

Simon E Spero (ses@tipper.oit.unc.edu)
Fri, 16 Sep 94 22:50:54 -0400


Data structures using ASN.1 and the PER are in many ways ideal for
a high performance HTTP protocol; however they perform a completely
different role to that of mime types. MIME typing is a notation designed to
indicate the type of an object carried within an envelope; mime also allows
a mail message to contain multiple objects through the multipart hack, but this
is orthogonal to its object typing role.

Using a proper presentation layer such as ASN.1/PER allows several major
optimisations to be performed. For example, Type perferences can be represented
as an ordered sequence of bit sets, allowing object type negotiaion to be
performed with just mask and match, many orders of magnitude faster than
processing 1K of object headers. A properly designed protocol can also take
advantage of PER to indicate multiple options, such as request for headers only
and checkout locks in a regular and orthogonal way, vastly simplifying te
design.

Simon