Browse Prior Art Database

Ethernet Bandwidth Management

IP.com Disclosure Number: IPCOM000111767D
Original Publication Date: 1994-Mar-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 4 page(s) / 217K

Publishing Venue

IBM

Related People

Baugher, M: AUTHOR

Abstract

Collision-detection protocols such as Ethernet make no provision for supporting classes of service as found on the Token Ring, using priority, and FDDI, using synchronous service. This makes the task of supporting multimedia traffic more difficult since applications that use sound, voice and video require quality of service guarantees for delay and throughput. This class of traffic needs to be identified and treated differently on the Ethernet if bandwidth is to be guaranteed. It is urgent that a solution be found for Ethernet, since it has the largest installed base of any local area network (LAN). This article discloses a configuration and an implementation for providing guaranteed bandwidth (throughput and delay guarantees) on the Ethernet.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 28% of the total text.

Ethernet Bandwidth Management

      Collision-detection protocols such as Ethernet make no
provision for supporting classes of service as found on the Token
Ring, using priority, and FDDI, using synchronous service.  This
makes the task of supporting multimedia traffic more difficult since
applications that use sound, voice and video require quality of
service guarantees for delay and throughput.  This class of traffic
needs to be identified and treated differently on the Ethernet if
bandwidth is to be guaranteed.  It is urgent that a solution be found
for Ethernet, since it has the largest installed base of any local
area network (LAN).  This article discloses a configuration and an
implementation for providing guaranteed bandwidth (throughput and
delay guarantees) on the Ethernet.

      This invention implements bandwidth reservation on a
collision-detection Local Area Network (LAN) such as Ethernet to
create two classes of traffic: reserved and unreserved traffic.
Bandwidth reservation is one way to provide network service
guarantees since a station, protocol, or application is assured of
getting a certain amount of service (e.g., bytes transmitted) over
some interval of time.  The applications which may benefit from this
invention are multimedia playback applications and multimedia
teleconferencing.  Two multimedia playback reference configurations
are shown in Fig. 1.  Each configuration features a multimedia file
server labelled as "MM Server".  In Fig. 1(a), the bandwidth
reservation can be performed at the medium access control (MAC) layer
since there is no more than a single "hop" or link between the client
workstation and the server.  In Fig. 1(b), link or network protocol
is needed since an intermediate node, which can be a bridge, router
or gateway is needed to transfer traffic across two or more LAN
segments.  This invention only applies to configuration (a), not (b),
in Fig. 1.  But experience has shown that many potential customers
can benefit from a dedicated multimedia server that is directly
connected to all LAN segments which it serves.  For large enterprises
where the server is accessed infrequently by LAN-attached
workstations, it is useful to provide the remote access shown in (b).
But in small or medium-sized campus environments, multimedia servers
configured according to Fig. 1(a) will solve many, if not most,
customer environments.  This is true because of the limited number of
concurrent sessions which can be supported by multimedia servers.
Moreover, some future customer premises networks (CPNs) such as
B-ISDN CPNs will more closely resemble configuration (a) rather than
configuration (b).  Note that what has been claimed for multimedia
file servers applies equally well to multimedia conferencing
"servers" or multipoint control units which will share a common
network infrastructure with file servers - the Multimedia LAN and
Multimedia Bridge infrastructure.

      When a "Multimedia LAN"...