RFC 1363 (rfc1363) - Page 1 of 20
A Proposed Flow Specification
Alternative Format: Original Text Document
Network Working Group C. Partridge
Request for Comments: 1363 BBN
September 1992
A Proposed Flow Specification
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard. Distribution of this memo is
unlimited.
Abstract
A flow specification (or "flow spec") is a data structure used by
internetwork hosts to request special services of the internetwork,
often guarantees about how the internetwork will handle some of the
hosts' traffic. In the future, hosts are expected to have to request
such services on behalf of distributed applications such as
multimedia conferencing.
The flow specification defined in this memo is intended for
information and possible experimentation (i.e., experimental use by
consenting routers and applications only). This RFC is a product of
the Internet Research Task Force (IRTF).
Introduction
The Internet research community is currently studying the problems of
supporting a new suite of distributed applications over
internetworks. These applications, which include multimedia
conferencing, data fusion, visualization, and virtual reality, have
the property that they require the distributed system (the collection
of hosts that support the applications along with the internetwork to
which they are attached) be able to provide guarantees about the
quality of communication between applications. For example, a video
conference may require a certain minimum bandwidth to be sure that
the video images are delivered in a timely way to all recipients.
One way for the distributed system to provide guarantees is for hosts
to negotiate with the internetwork for rights to use a certain part
of the internetwork's resources. (An alternative is to have the
internetwork infer the hosts' needs from information embedded in the
data traffic each host injects into the network. Currently, it is
not clear how to make this scheme work except for a rather limited
set of traffic classes.)
Partridge