Teletraffic Engineering Handbook.pdf

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ITU–D
StudyGroup2
Question16/2
Handbook
“TELETRAFFICENGINEERING”
Geneva,January2005
ii
iii
PREFACE
ThisfirsteditionoftheTeletracEngineeringHandbookhasbeenworkedoutasajoint
venturebetweenthe
•ITU–InternationalTelecommunicationUnion
<http://www.itu.int> ,andthe:
•ITC–InternationalTeletracCongress
<http://www.i-teletraffic.org> .
Thehandbookcoversthebasictheoryofteletracengineering.Themathematicalback-
groundrequirediselementaryprobabilitytheory.Thepurposeofthehandbookistoenable
engineerstounderstandITU–Trecommendationsontracengineering,evaluatetoolsand
methods,andkeepup-to-datewithnewpractices.Thebookincludesthefollowingparts:
•Introduction:Chapter1–2,
•Mathematicalbackground:Chapter3–6,
•Telecommunicationlossmodels:Chapter7–11,
•Datacommunicationdelaymodels:Chapter12–14,
•Measurements:Chapter15.
Thepurposeofthebookistwofold:toservebothasahandbookandasatextbook.Thus
thereadershould,forexample,beabletostudychaptersonlossmodelswithoutstudying
thechaptersonthemathematicalbackgroundfirst.
ThehandbookisbasedonmanyyearsofexperienceinteachingthesubjectattheTech-
nicalUniversityofDenmarkandfromITUtrainingcoursesindevelopingcountriesby
theeditorVillyB.Iversen. ITU-TStudyGroup2(WorkingParty3/2)hasreviewed
Recommendationsontracengineering.Manyengineersfromtheinternationalteletraf-
ficcommunityandstudentshavecontributedwithideastothepresentation.Supporting
material,suchassoftware,exercises,advancedmaterial,andcasestudies,isavailableat
<http://www.com.dtu.dk/teletraffic> ,wherecommentsandideaswillalsobeappreci-
ated.
ThehandbookwasinitiatedbytheInternationalTeletracCongress(ITC),Committee3
(DevelopingcountriesandITUmatters),reviewedandadoptedbyITU-DStudyGroup2
in2001.TheTelecommunicationDevelopmentBureauthankstheInternationalTeletrac
Congress,allMemberStates,SectorMembersandexperts,whocontributedtothispublica-
tion.
HamadounI.Tour´e
Director
TelecommunicationDevelopmentBureau
InternationalTelecommunicationUnion
iv
v
Notations
a Carriedtracpersourceorperchannel
A Oeredtrac=A o
A c Carriedtrac=Y
A ` Losttrac
B Callcongestion
B Burstiness
c Constant
C Traccongestion=loadcongestion
C n Catalan’snumber
d Slotsizeinmulti-ratetrac
D Probabilityofdelayor
Deterministicarrivalorserviceprocess
E Timecongestion
E 1,n (A)=E 1 Erlang’sB–formula=Erlang’s1.formula
E 2,n (A)=E 2 Erlang’sC–formula=Erlang’s2.formula
F Improvementfunction
g Numberofgroups
h Constanttimeintervalorservicetime
H(k) Palm–Jacobæus’formula
I InversetimecongestionI=1/E
J (z) ModifiedBesselfunctionoforder
k Accessibility=huntingcapacity
Maximumnumberofcustomersinaqueueingsystem
K Numberoflinksinatelecommuncationnetworkor
numberofnodesinaqueueingnetwork
L Meanqueuelength
L Meanqueuelengthwhenthequeueisgreaterthanzero
L Randomvariableforqueuelength
m Meanvalue(average)=m 1
m i i’th(non-central)moment
m 0 i i’thcentralemoment
m r Meanresiduallifetime
M Poissonarrivalprocess
n Numberofservers(channels)
N Numberoftracstreamsortractypes
p(i) Stateprobabilities,timeaverages
p{i,t|j,t 0 } Probabilityforstateiattimetgivenstatejattimet 0
Zgłoś jeśli naruszono regulamin