Table Of ContentLocal Area Network
Interconnection
Local Area Network
Interconnection
Edited by
Raif O. Onvural
IBM
Research Triangle Park, North Carolina
and
Arne Nilsson
North Carolina State University
Raleigh, North Carolina
Springer Science+Business Media, LLC
Librar y o f Congress Cataloglng-in-PublIcatio n Data
Local are a networ k Interconnectio n / edite d by Raif 0. Onvural, Arne
Ni1sson.
p. cm .
"Proceedings o f th e Firs t Internationa l Conference on Local Are a
Network Interconnection , hel d October 20-22, 1993, i n Research
Triangl e Park , North Carolina" —
Includes bibliographica l reference s and index .
ISBN 978-1-4613-6282-1 ISBN 978-1-4615-2950-7 (eBook)
DOI 10.1007/978-1-4615-2950-7
1. Local are a network s (Computer networks)—Congresses .
I. Onvural, Rai f 0. , 1959- . II . Nüsson , Arne .
III . Internationa l Conference on Local Are a Network Interconnectio n
(1st : 1993 : Research Triangl e Park, N.C. )
TK5105.7.L582 199 3
004.6' 8—dc20 93-637 0
CIP
Proceedings of the First International Conference on Local Area Network
Interconnection, held October 20-22, 1993, in Research Triangle Park, North
Carolina
ISBN 978-1-4613-6282-1
© 1993 Springer Science+Business Media New York
Originally published by Plenum Press, New York in 1993
Softcover reprint of the hardcover 1st edition 1993
All rights reserved
No part of this book may be reproduced, stored in retrieval system, or transmitted in any form or by any
means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written
permission from the Publisher
COMMITTEES
Conference Co-Chairs
R.O. Onvural, IBM, ResearchTrianglePark
A. A. Nilsson, NCSU
Organizing Committee
J.Fjeld, IBM
J.Hart,3Com
L. Kleinrock, UCLA
F. Marshall, CISCO
H. Salwen, Proteon
M. Schwartz, Columbia University
G. C. Stone, NetworkSystems
Program Committee
P. Baker, England H. Perros, USA
S. Bradner, USA G. Pujolle. France
W. Bux, Switzerland D. Roffinella, Italy
A. Danthine, Belgium O. Spaniol, Germany
S. Fdida, France D. Stevenson, USA
L. Fratta, Italy H.Takagi, Japan
B. Gavish, USA K. Tolly, USA
J.Gray,USA K. Trivedi. USA
U. Korner, Sweden Y. Viniotis, USA
J-Y. LeBoudec, Switzerland H. Yamashita.Japan
P. Martini. Germany
Conference Secreteriat
Y.C. Liu, IBM
Local Arrangements
M. Hudacko, NCSU
B. Sampair, IBM
Sponsored by
IEEEComm. Soc. Eastern NCChapter
IBM·Research Triangle Park
The Centerfor Communications and Signal Processing
In cooperation with
Interlab
IFIPTC6TaskForceonthe PerformanceofComputerNetworks
IFIPWorking Group 7.3
IFIPWorkingGroup6.4
PREFACE
There are many exciting trends and developments in the communications
industry, several ofwhich are related to advances in fast packet switching, multi
media services, asynchronous transfer mode (ATM) and high-speed protocols.
It seems fair to say that the face of networking has been rapidly changing and
the distinction between LANs, MANs, and WANs is becoming more and more
blurred. It is commonly believed in the industry that ATM represents the next
generation in networking. The adoption of ATM standards by the research and
development community as a unifying technology for communications that
scales from local to wide area has been met with great enthusiasm from the
business community and end users.
Reflecting these trends, the technical program of the First International
Conference on LAN Interconnection consists of papers addressing a wide
range of technical challenges and state of the art reviews. We are fortunate to
have assembled a strong program committee, expert speakers, and panelists.
We would like to thank Professor Schwartz for his keynote speech. We would
liketo thank ProfessorYannis Viniotis and his studentsforthe preparation ofthe
index. We gratefully acknowledge the generous financial support of Dr. Jon
Fjeld, Mr. Rick McGee, and Mr. David Witt, all of IBM-Research Triangle Park.
We also would like to thank Ms. Mary Safford, our editor, and Mr. John Matzka,
both at Plenum Press, for the publication ofthe proceedings.
RaifO. Onvural
Arne A. Nilsson
vii
CONTENTS
QoSEnhancementsandthe NewTransportServices 1
A. Danthine, O. Bonaventure, Y. Baguette, G. Leduc, and L. Leonard
Performance Evaluation and Monitoringof HeterogeneousNetworks 23
J. Neuman, S. Lalanne, F. Georges, andJ. P. Claude
Application ofHigh Speed Networksin Hospital Environment... 39
J.R. Rao
On Allocation Schemes for the Interconnection of LANs and Multimedia
SourcesoverBroadbandNetworks .47
M. Mateescu
ASuperposition of Bursty Sources in aLAN Interconnection Environment.......65
J. M. Karlsson
Interconnecting LANsfor RealTimeTrafficApplication 79
I. Chlamtac
An Analytical Model for ATM Based Networks which Utilize Look·Ahead
ContentionResolution Switching 93
J. V. Luciani and C. Y. RogerChen
Transient Analysis of Nonhomogenous Continuous Time Markov Chains
Describing RealisticLAN Systems 109
A. Rindos, S. Woolet, and I. Viniotis
Closed Queueing Network Modeling for End-to-End Performance
Analysis of ISO LLC and Transport Protocolsover
BridgedNetworks 125
T.lkegawa
APreviewofAPPN HighPerformanceRouting 139
J.P. Grayand M. L. Peters
Analysis of the Spanning Tree and Source Routing LAN
InterconnectionSchemes 161
M. Munafo, F. Neri, C. S. Cioffari, and A. Vasco
Efficient, Real-TimeAddress Resolution in Backbone Networks 183
W.A. Doeringer, H.D. Dykeman, M. L. Peters,
H. J. Sandick, and K. V. Vu
ix
Architecture and Performance Evaluation for High Speed LAN
InternetworkingProcessors 193
K. Taniguchi, H. Suzuki, and T. Nishida
Implicationsof Internet Fragmentation and Transit Network
Authentication 209
R.L. Popp
Local Area Network Traffic Locality: Characterization and Application 233
N. Gulati, C. L. Williamson, and R. B. Bunt
Characterizationofthe TrafficattheOutputofaDODBMAN 251
M. A. Marsan, G. Albertengo, R. Lo Cigno, M. Munafo, F. Neri,
and A. Tonietti
Interworking Functions Effect on Bandwidth Allocation for
LAN-BISON Interconnection 269
I.S. Venieris, J.-A. Sanchez-Papaspiliou, and M. E. Anagnostou
Multi-ChannelToken Ring, Introduction and Throughput Analysis 287
K. J. Christensen and F. E. Noel
Parallel Networking: Improving Capacity and Multi-Traffic Performance
Together 297
E.C. Foudriat, K. Maly, R. Mukkamala, and C. M. Overstreet
TheJourneyofSMDS--ALAN InterconnectSolution 313
M. Joshi and F. Lai
InterworkingofB-ISDN and DODB--ASimulation Study 327
P. Martini and M. ROmekasten
Performance Evaluation of aBuffered ATM Connectionless Server 343
K. Kvols and E. Vazquez
Index 355
x
QoS ENHANCEMENTS AND THE NEW TRANSPORT SERVICES
AndreDanthine,OlivierBonaventurel,YvesBaguette2,
GuyLeduc3andLucUonard2
1 ResearchAssistantoftheUniversitedeLiege
2 ResearchAssistantoftheEN.R.S. (NationalFundfor Scientific
Research,Belgium)
3 ResearchAssociateoftheEN.R.S.
Institutd'ElectriciteMontefiore,B28
UniversitedeLiege,
B-4000,LIEGE,Belgium
E-mail:[email protected]
INTRODUCTION
The transportprotocolsTCPandTP4havebeendesignedin thelateseventiesatatime
whenthenetworkenvironmentwasessentiallybasedontheswitchedtelephonenetworkand
onleased-linesandwhenthepacketswitchingwasanemergingconcept.
In ISO, the transport service was seen at the beginning as a unique service basedon
connectionmodeand, inthisframework, oneprotocolclass,TP4,wasdesignedforthepoor
network serviceenvironment [Dan 90]. TP4, as well as TCP, were designed to be able to
recoverfromtheworstsituationintermsofpacketlossesandpacketdisorders.
In the last ten years, we have seen a tremendous change in the communication
environment. TheLANs havedrasticallychangedthesceneandthe high-speedLANs have
acceleratedthetrend. Morerecently,theMANshaveopenednewpossibilitiesnottomention
thebroadbandISDNwhichisexpectedtobedeployedstartinginthemiddleofthisdecade.
Notonlythe communicationenvironmenthasdrasticallychangedduring the eighties,
butwehavealsofacedadrasticchangeinapplicationrequirementsofwhichwewillmention
onlytheclient-serverparadigmandthemultimedia-basedapplications.
In thispaperwewillfirstjustifythe needofnewtransportservicesandprotocolsbased
ontheanalysisoftheconsequencesofthechangeswehavebeenfacing
innetworkperformance
innetworkservices
inapplicationrequirements.
We will,inthesecondpart,presentanenhancementoftheQoS semanticsinordertobe
able to specify the new transport service in a way compatible to the requirements ofthe
transportserviceusers. Inourproposed semantics, aQoS parameteris seenas astructureof
threevalues,respectivelycalled "compulsory", "threshold" and "maximalquality",all these
values being optional. Each one expresses a contract between the service users and the
serviceprovider. This means, and this is the mostfundamental difference with the present
situation,thattheserviceproviderisnowsubmittedtosomewelldefinedduties.
Thelastpartofthepaperwill beabriefpresentationofexamplescomingfrom theOSI
95transportservices.
LocalAreaNetworkInterconnection, EditedbyR.O.Onvural
andA.A.Nilsson,PlenumPress, NewYork, 1993
CHANGE IN NETWORK PERFORMANCE
LetusfirstpointouttherobustnessoftheOSIReferenceModelwhichhasbeenableto
integratethe LANsinitslayeredarchitecture [Dan 89] andisverylikely tointegratetheB
ISDN.
The basiccontributionsoftheLANs have been adrasticimprovementofthe network
performancein termsofdatarateaswellasin termsofbiterrorrate(BER)andpacketerror
rate. TheerrorrecoverywasnotanymoreabasicgoaloftheDLlayerandthisexplainedthe
tremendoussuccessoftheconnectionless-mode.
TheLANs havenotonlyintroducedanincreaseoftheglobalcommunicationcapability
due to the highvalueoftheirdatatransmission rate but,moreimportant, they haveoffered
the user an access data rate several orders ofmagnitude greater than what was available
before.
If, as usual, thefirst implementationsofthe LANcontrollerswere not always able to
offer the maximum access rate theoretically available at the MAC level [DRR 88a], the
market, in about five years, was able to offer well-designed and well-implemented LAN
interfaces.
ItdidnottakelongtorealisethatanaccessrateavailableattheMACorLLClevelswas
farfrom beingavailableabovethe transportlayer[DHH 88a][Svo89a, 89b][ReS 89][CCC
91]. Thisis notsurprising,becauseopeningahighwaydoes notby itselfchangedrastically
thespeedofthebicycles.
How to Improve ?
From the observations made in the second half of the eighties about the transport
performanceontopofLANs,detailedstudiesofmechanismsandimplementationshavebeen
done [CJR 89], [GKW 89], [Mei 91], [JSB 90], [Zitt 91] and ended up in two different
schoolsofthought.
Thefirst schooladvocatedthedesignofnewtransportprotocolssuchasNETBLT[CLZ
87],VMTP[Che 88],[ChW89],SNR[NRS 90] andXTP [Ches 89], [Wha 89], [PE91].
The second school is putting the burden ofthe poortransport performance to the bad
implementationqualityandisclaimingthecapabilityofexistingorslightlymodifiedtransport
protocolstobetterhandletheperformanceavailableattheMAClevel [CJR89].
Bothschoolshaveargumentsandwewouldlikeheretodiscussthem,keepinginmind
thatthese LANsdo notonlyofferabetteraccessrate, they arealsocharacterisedbyavery
lowprobabilityofcorruptedpacketsbytransmissionerrors.
Mechanisms and Implementations
We claimthat there is abasic interest to adaptorto modify the protocol mechanisms
when the network service is drastically changing. The following example will supportour
claim.
NetworkServiceProvider
Figure1.ThebasicOSIreference model
2
The figure 1represents a simplified view ofthe basic OSI reference model and we
assume,on theNSAP-to-NSAPassociation, aguaranteedthroughputandafixed roundtrip
time. On top of such an well-definedN-service, weassumean idealimplementationofthe
transportentitieswhichdoesnotintroduceanylatencytoprocessTSDUsintoNSDUs. This
does notmeanhoweverthatthe throughputand theround-tripdelayon theTSAP-to-TSAP
association,sayatransportconnection,willbeequivalenttothevaluesatthenetworklevel.
Theproductof"throughputxround-trip delay" -alsocalled"bandwidth xdelay" -is
becoming,with highspeednetworks,animportantcharacteristictobedealtwith.Thevalue
ofsuch aproduct has evolved from 1Kb (2 Kbps x500 msec) to 600 Kb (10 Mbps x60
msec), not to mention the very high speed environment. Ifthe window associated with a
transportconnectiondoes notallow the pipeliningofenoughmegabits, thetransportentity
willbeobligedtostoptransmittingbylackofacknowledgementsandofflow controlcredits.
Thereforetheperformanceatthetransportlevelwillbemuchlowerthantheperformanceat
thenetworkleveleven with an ideal implementation of the transport layer.
On the other hand, if protocol mechanisms may have such an influence on the
performanceeven with an ideal implementation, it is also true that somemechanisms may
induce very poor implementations. For instance a time-out per packet is not the best
mechanismfromanimplementationpointofview.
With a transport entity trying to send as many packets as possible, alot ofACKs to
handlerepresentsaburdenandtheclassicalARQmechanismhasthereforetobereviewedto
reducethepenaltiesonperformance.
Lastbutnotleast,thereremainimplementationproblemswhichareindependentofany
protocolmechanismsuchasbufferhandlingandinteractionwiththeoperatingsystem[CJR
89], [MaB91].
There exist ofcourse many choices ofimplementation from VLSI to pure software,
moreorlessintegratedin theoperatingsystem,usingadditionaldedicatedcomputingpower
ornot [GKW89], [JSB 90], [Zitt91] .
The syntaxes ofthe PDU are not neutral with respect to the implementation results.
Variable fields may save bandwidthbutare moredifficult to"siliconize".The placeofthe
CRC field in the PDU is also important if hardware implementation with insertion and
removal"onthefly"isenvisaged.
With the availabilityofmicroprocessorsofmore than 10Mips, with thepossibility to
use parallelism in the implementation of the transport entities, with the possible use of
dedicatedchips,wehaveawidevarietyofpossibleimplementationsofthetransportentities,
all of them attempting to offer a transport service with a minimum drain on the host
capabilities.
Theconclusiontothissectiononthelinkbetweenmechanismsandimplementationsis
thatevenifitis true that the implementationofthe protocol mechanisms is notalways the
most timeconsumingpartofthe transport activity, it will not be bad to have mechanisms
which are well-alignedwith theobjectivesand servicesofthe protocol and which willease
theimplementationproblems.Thisdoesnotpreventofcourseacarefulchoiceofthesyntaxes
ofthePDUsandanin-depthanalysisofthememorymanagement.
The Congestion Problem
During the eighties, we have not only seen the widespread usage ofthe LANs and
recentlyofthehigh-speedLANs. We havealsoseenthe buildingofvery biginternet-based
networksfollowing theeffortssupportedbytheUS DoD.
Suchan internetnetworkmaygiverisetoverydifficultproblemsofcongestionwhich
arealmostimpossibletotacklewiththeerrorrecoverymechanismwhichhasbeenintroduced
inTCPandTP4. Thecorrectingaction ofthe transportprotocolin ordertorecoverthe lost
packetsdue tothecongestionis basedonretransmissionontime-out.Theseretransmissions
contribute to an increase of the offered load and therefore to increase the congestion
problems.
Thisis whycongestionavoidance mechanisms which try tooperatethenetworkatthe
kneeofthe response timecurve [Raj 88], [ChJ 89] have to be preferred to thecongestion
controlapproach.Time-outretransmissionmustbeassociatedwithareductionoftheloadon
thenetwork[Jai86].
In the congestion problems, we have also two possible viewpoints. Either the
mechanismsareaimingattheprotectionoftheprovideroftheservice,Le. thenetworkitself,
inordertoavoidacompletecollapseofcommunicationcapability.Either,theyareaimingat
3
