RFC 1453 (rfc1453) - Page 1 of 10
A Comment on Packet Video Remote Conferencing and the Transport/Network Layers
Alternative Format: Original Text Document
Network Working Group W. Chimiak
Request for Comments: 1453 BGSM
April 1993
A Comment on Packet Video Remote Conferencing and the
Transport/Network Layers
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
The new generation of multimedia applications demands new features
and new mechanisms for proper performance. ATM technology has moved
from concept to reality, delivering very high bandwidths and new
capabilities to the data link layer user. In an effort to anticipate
the high bandwidth-delay data link layer, Delta-t [Delta-t], NETBLT
[RFC 988], and VMTP [RFC 1045] were developed. The excellent
insights and mechanisms pioneered by the creators of these
experimental Internet protocols were used in the design of Xpress
Transfer Protocol (XTP) [XTP92] with the goal of eventually
delivering ATM bandwidths to a user process. This RFC is a vehicle
to inform the Internet community about XTP as it benefits from past
Internet activity and targets general-purpose applications and
multimedia applications with the emerging ATM networks in mind.
1. Introduction
Networking is no longer synonymous with analog telephony. High-
performance lower-layer networks have made possible exciting new
applications: collaboratory environments, distributed client/server
computing, remote conferencing, teleclassrooms, and distributed
life-sciences imaging. These applications normally demand a great
deal of bandwidth and often create operating system bottlenecks.
Enabling these new multimedia applications entails delivering
bandwidth to the applications, not just having bandwidth available on
the network. This statement may appear obvious, but often solutions
at the transport layer are satisfied by having bandwidth at that
layer without sufficient sensitivity to higher-layer access to the
bandwidth. The unavailability of bandwidth at upper layers is
becoming the real issue as the networks are becoming a high-
performance virtual backplane without concomitant high-performance
control schemes. It appears that new services are needed that
require communication with all layers. The ATM architecture calls
Chimiak
