In e na ional Jou nal o So wa e Enginee ing & Applica ions (IJSEA), Vol.10, No.1, Janua y 2019
DOI: 10.5121/ijsea.2019.10103 37
A
PPLYING
C
ONTINUOUS
I
NTEGRATION
F
OR
I
NCREASING
T
HE
M
AINTENANCE
Q
UALITY
A
ND
E
FFICIENCY
O
F
W
EB
A
PP
Sen-Ta ng Lai
Dep . o In o ma ion Technology and Managemen , Shih Chien Uni e si y,
Taipei, 10462, Taiwan
A
BSTRACT
In o de o p ojec esou ce managemen and ime con ol, so wa e sys em needs o be decomposed in o
subsys ems, unc ional modules and basis componen s. Finally, all es ed componen s ha e o in eg a e o
be he comple e sys em. Applying IID (I e a i e Inc emen al De elopmen ) mechanism, agile de elopmen
model becomes he p ac ical me hod o educe so wa e p ojec ailu e a e. Con inuous in eg a ion (CI) is
an IID implemen a ion concep which can e ec i ely educe so wa e de elopmen isk. Web app wi h high
change cha ac e is ic is sui able o use agile de elopmen model as he de elopmen and main enance
me hodology. The pape dep h su eys CI ope a ing en i onmen and ad an ages. In oducing CI concep
can make up he mo ing a ge p oblems o impac o Web app. Fo his, he pape p oposes a Con inuous
In eg a ion based Web Applica ions Main enance P ocedu e (CIWAMP) o assis he sys em in eg a ion
ope a ing. Based on CI cha ac e is ics, CIWAMP makes Web app can be deployed quickly, inc ease
s akeholde communica ion equency, imp o e s a mo ale, and e ec i ely educe Web app main enance
quali y and e iciency.
K
EYWORDS
Con inuous In eg a ion, agile p ocess, Web app, in eg a ion es , main enance quali y and e iciency
1. I
NTRODUCTION
Web applica ions (Web app) de elopmen p ocess mus o e come he challenges o
en i onmen al changes and many kind o se ices eques s. Fo e ec i ely educing de elopmen
isks, Web app mus dec ease he impac o all o changes [1], [2]. Many e en s, which include
e o co ec ion, equi emen speci ica ion e ision, en i onmen e olu ion, and esou ce
adjus men o en cause o p ojec plan changes. Any plan change always a ec s so wa e
de elopmen ope a ion. Plan changes no only ha e o in es ex a esou ce and cos , bu also
cause some ela ed bugs and issues [3], [4]. In eques s change p ocess, he a ec ed de elopmen
documen s and sou ce code unable o e ec i ely e ise, es and in eg a e, will inc ease Web app
de elopmen isk. In addi ion, he implied issues and p oduced bugs unable o iden i y quickly
and modi y imely. The issues and bugs will low o he ollow phases o g ea ly educe Web app
success a io. Many ac o s may a ec Web app de elopmen isk. Howe e , one o c i ical
ac o s is he bugs and issues canno immedia ely iden i y and e ise. Fo his, Web app
de elopmen mus enhance he de ec s iden i ica ion and quick e ision mechanism o educe
isks o en i onmen al changes and modi ica ion eques s.
In cu en so wa e de elopmen p ocess, I e a i e and Inc emen al De elopmen (IID)
mechanism has become a new de elopmen end [5], [6]. RUP (Ra ional Uni ied P ocess) is a
widely used de elopmen model o objec -o ien ed analysis and design [6]. Agile p ocess e y
In e na ional Jou nal o So wa e Enginee ing & Applica ions (IJSEA), Vol.10, No.1, Janua y 2019
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ca es wo kable so wa e and uses ime-boxing app oach o con ol ime and i ems change isks
[6], [7], [8]. Using agile de elopmen model, he small scale so wa e p ojec has highe success
a io. RUP and agile p ocess combine wi h he IID mechanism o implemen he so wa e
de elopmen wo k. I e a i e de elopmen is o de elop job o epea edly use he same se ies o
ac ions o s eps, inc emen al de elopmen means ha e e y ime will be in he exis ing so wa e
sys ems, inc ease and o he new ea u es, modules o uni s. Agile de elopmen model o de elop
a e each i e a i e ope a ion comple e ope a ing sys em e sion, and immedia ely es and
e alua e his e sion. The p ocesses p oblems and he p oduc de ec s can be easily de ec ed o
help imely modi y and co ec measu es o educe he so wa e de elopmen isks. IID
mechanism g adually be aken se iously, many so wa e me hodologies combine wi h IID o
imp o e de elopmen quali y and p oduc i i y, among which con inuous in eg a ion (CI) wi h
agile de elopmen model mos ci ed and discussed [9], [10], [11], [12], [13]. CI is a concep o
implemen a ion. CI implemen a ion immedia e ad an age can ea ly ind so wa e sys em
p oblems and de ec s, educe so wa e de elopmen isks.
Web app wi h high change cha ac e is ic is sui able o use agile de elopmen model as a
de elopmen and main enance me hodology. In Web app de elopmen p ocess, agile model wi h
CI de elopmen concep can e ec i ely ind he p oblems and he de ec s ea ly, and imely
co ec o a oid he de ec s ou sp ead, g ea ly educe Web app de elopmen isks. Based on CI
ea u es, he c i ical componen s o CI en i onmen should be clea ly de ined and combined o se
up a pe ec CI ope a ing en i onmen . In addi ion, o building he common ecogni ion o
so wa e de elope s, he pape p oposes he Con inuous In eg a ion based Web Applica ions
Main enance P ocedu e (CIWAMP). Using CI en i onmen o Web app main enance, au oma ed
in eg a ion es ing can quickly assis p oduc deploymen , imp o e s akeholde communica ion,
inc ease s a mo ale and o he cha ac e is ics, and e ec i ely inc ease quali y and p oduc i i y o
Web app main enance. In Sec ion 2, he ad an age o agile de elopmen model and he CI
ea u es a e discussed. In Sec ion 3, desc ibes he cha ac e is ics o Web app and discusses he
exis ed main enance p oblems o Web app. CI concep mus wi h a sound ope a ing en i onmen
o play o i s eng hs, in Sec ion 4, de ines he pe ec CI en i onmen and p esen s he
CIWAMP. In Sec ion 5, e alua es he ad an ages o CI wi h CIWAMP. In Sec ion 6, emphasizes
he s eng hs o CIWAMP o inc ease he main enance quali y and e iciency o Web app, and o
d aw conclusions o he opic.
2. A
GILE
D
EVELOPMENT
A
ND
C
ONTINUOUS
I
NTEGRATION
Combining agile de elopmen model wi h CI can inc ease so wa e de elopmen quali y and
p oduc i i y.
2.1. A
GILE
S
OFTWARE
D
EVELOPMENT
In ecen wen y yea s, he g ow h o in o ma ion echnology, ope a ional en i onmen and use
equi emen s, so wa e de elopmen me hodologies con inuously p og ess. Mos so wa e
de elopmen models ha e high ela ionship wi h he use equi emen s. Wa e all model de ines
clea phase mission and e y conce ns he phase documen s [6]. The quali y o equi emen
documen s can' each co ec ness, comple eness and consis ency, de elopmen p ocess will be
denied o en e he ollowing phase. Recen ly p oposed de elopmen models ha e modi ied
equi emen speci ica ion s yle. The equi emen i ems a e allowed o p opose by inc emen al
manne , no necessa y o decision a same ime [5], [6]. By i e a i e de elopmen model, use can
inc emen ally p o ide he equi emen i ems. So wa e de elopmen isks can be g ea ly educed.
Each de elopmen model should has he adjus men s a egy o handle he change o use
In e na ional Jou nal o So wa e Enginee ing & Applica ions (IJSEA), Vol.10, No.1, Janua y 2019
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equi emen s. The adjus men s a egy can' e ec i ely educe he so wa e de elopmen isks ha
may impac success a io o so wa e p ojec .
In Feb ua y 2001, se en een so wa e de elope s me a he U ah (ski eso ) o USA and
p oduced he Mani es o o he agile so wa e de elopmen [6]. Many o pa icipan s had
p e iously au ho ed hei own so wa e de elopmen me hodologies, including Ex eme
p og amming, C ys al, and Sc um [6], [7], [8]. Agile so wa e de elopmen p oposes se e al
c i ical iewpoin s [7], [8]:
(1) In de elopmen p ocess, does no conce n analysis and design phase ope a ions and
documen s.
(2) As soon as possible o en e p og amming phase, wo kable so wa e is mo e p ac ical han
de elopmen documen .
(3) Suppo and p o ide high changeabili y so wa e sys em.
(4) Enhance he coope a i e ela ionship be ween de elope and use , use can ully a end he
de elopmen eam.
In ime managemen side, agile so wa e de elopmen applies ime-boxing app oach o con ol
p ocess schedule [6], [8]. Reques ed so wa e p ojec mus elease a new e sion in wo o h ee
weeks. Le clien clea ly unde s and he de elopmen p og ess and es , audi he equi emen o
new e sion. In each day, a i een minu es s and up mee ing is ixedly held o e ec i ely each
he ully communica ion be ween clien and de elope s. In addi ion, agile p ocess uses i e a i e
and inc emen al de elopmen o educe he equi emen complexi y, e ac o ing o inc ease he
equi emen modi ied lexibili y, non-documen o ien ed can educe he cos o equi emen s
change. In de elopmen change impac s, agile de elopmen g ea ly dec eases schedule delay, cos
excess budge and quali y unsa is ied use equi emen si ua ions, so wa e de elopmen change
isk can be e ec i ely educed. Howe e , agile p ocess neglec s he o mal analysis and design
phases, uses non-documen o ien ed de elopmen , and doesn’ pay a en ion o ollow-up
main enance ope a ion ha a e majo d awbacks. Fo e ec i ely educing he so wa e
de elopmen isks, he d awbacks o agile p ocess should be conc e ely imp o ed o enhanced.
2.2. A
DVANTAGES
O
F
C
ONTINUOUS
I
NTEGRATION
CI is a so wa e enginee ing p ac ice in which new i ems and changes a e immedia ely es ed and
epo ed on be o e hey a e check-in o a sou ce eposi o y. The goal o CI is o iden i y he
so wa e e o s and de ec s quickly, and o make he e o s and de ec s can be co ec ed and
e ised as soon as possible. In 1994, G ady Booch men ioned he CI phase in his book o Objec -
O ien ed Analysis and Design wi h Applica ions [14]. In 1997, Ken Beck and Ron Je ies
p oposed XP which included CI concep [9], [11]. In 1998, Ken published a pape o CI which
alued and suppo ed he impo ance o di ec ly communica ion echnology. Based on IID
mechanism, agile de elopmen combines XP [15], [16], TDD (Tes D i en De elopmen ) [17],
and BDD (Beha io s D i en De elopmen ) me hods [18], and makes CI o become a main s eam
and impo an end o so wa e de elopmen . Focus on he au oma ic and epea p ocess a e he
majo cha ac e is ics o CI. The e o e, in eg a ed wi h ela ed au oma ed de elopmen ools is
i s mission o CI en i onmen .
In so wa e de elopmen p ocess, so wa e p ojec managemen applies modula iza ion o enable
eamwo k de elopmen and make complex sys em manageable. Modula iza ion decomposes he
complex so wa e sys em in o many manageable p og am uni s [6], [19]. Each p og am uni jus
handle a speci ic unc ion, he e o e he p og am uni s ha e o wo k oge he and in eg a e in o a
module unc ion, subsys em and sys em. CI h ough mo e imes in eg a ion and es ing makes he
In e na ional Jou nal o So wa e Enginee ing & Applica ions (IJSEA), Vol.10, No.1, Janua y 2019
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e o s and de ec s can be iden i ied quickly [20]. E o s co ec ion and de ec s e ision can be
handled imely and g ea ly a oid o ans e and ex end o he ollow phases. Summa ize i e
majo ad an ages o CI and discuss as ollows (shown as igu e 1):
High e iciency: CI combines many au oma ed ools and p ocedu es can inc ease he
de elopmen and ope a ion e iciency.
Reduce de elopmen isks: Acco ding o de elopmen eques s, CI can mo e imes in eg a e
in a day o educe so wa e p ojec de elopmen isks.
Smoo h communica ion: CM sys em, sou ce eposi o y and wo kable so wa e can assis
build common unde s anding among s akeholde .
Imp o emen quali y: CI ollows he sys ema ic p ocedu es and combines use ul au oma ed
ools o imp o e so wa e de elopmen quali y.
Inc eased mo ale: CI inc eases communica ion equency, d ama ically educing
communica ion ba ie s and so wa e de elopmen isks. The de elopmen eam con idence
can be es ablished and mo ale can be inc eased.
Figu e 1. Fi e majo ad an ages o CI
3.
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EB
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PP
C
HARACTERISTICS
A
ND
M
AINTENANCE
P
ROBLEMS
High changeabili y is a c i ical ac o o cause he Web app de elopmen isks. Quickly handle
change eques s can educe change isks o Web app de elopmen .
3.1
C
HARACTERISTICS
O
F
W
EB
A
PP
In Web app de elopmen p ocess, i is necessa y o ace challenge o many changes. Upda ing,
equi emen speci ica ions e ision, en i onmen e olu ion, and esou ce adjus men e c.
si ua ions possibly cause o ail o Web app de elopmen . I is because ha some cha ac e is ics
o Web app di e s om he gene al applica ions. Abou he cha ac e is ics o Web app a e
desc ibed as ollows:
F iendly use in e ace: In gene al, Web app use can
’
accep complex in e ace. Simplici y
and high iendly use in e ace is a c i ical ac o o a ac use and also is a i s s ep o
Web app success.
Ad an ages
o
CI
Smoo h
Communica ion
Inc eased
Mo ale
Reduce
De elopmen
Risks
Imp o emen
Quali y
High
E iciency
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Bea a wide ange o use s: Web app belongs o public b owsing sys em. The e o e, i mus
ha e high ole ance o accep all kinds o use and accep many kinds change o unc ion
eques s
Rapidly accomplish change se ice eques s: Wi h apidly changing echnology and a wide
ange o In e ne use s, mul i-s yles change se ice eques s a e submi ed con inuously.
Web app wi h high main ainabili y can quickly accomplish change se ice eques s.
Timely add new se ice i ems: Belong o he public b owsing sys em, Web app need deal
wi h many iews and new se ice eques s. The p oposed se ice eques s by ela ed uni s
ha e i s imeliness. The e o e, high main ainabili y is necessa y condi ion o imely add new
se ice i ems o Web app.
Quick mig a ion o new pla o m: Subsc ibe o success ul Web app will g ow con inuously.
Fo p o iding high se ice quali y, ope a ing en i onmen o Web app should be imely
adjus ed o enhanced. Web app can imely mig a e o he mo e pe ec wo king
en i onmen , app li e cycle can be ex ended conc e ely.
High in eg a ion abili y: Mul i-laye s a chi ec u e ope a ion en i onmen is a key a ibu e
o Web app. In o de o p o ide mul i-s yle se ices, Web app should emphasize on
in eg a ion and combina ion wi h he ela ed sys ems. High in eg a ion abili y is a necessa y
and c i ical cha ac e is ic o Web app.
Mul i-laye a chi ec u e is he majo ope a ing en i onmen o Web app. The e o e, Web app
de elopmen e y ca e abou analysis, p elimina y design and de ailed design. Analysis and
p elimina y design ocus on sys em a chi ec u e design and ex e nal en i ies in e ace design
which belong o sys em planning and ex e nal in e ace ela ed design. De ailed design ocuses on
he modula ized unc ion design and basic le el componen design which belong o sys em
in e nal da a s uc u e and logic ope a ion ela ed design. Acco ding o ope a ing en i onmen ,
ypes o use , de elopmen ools and main enance manne , special a ibu es o Web app can
clea ly iden i y he di e ence wi h gene al applica ion so wa e.
3.2
W
EB
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PP
M
AINTENANCE
P
ROBLEMS
Fo mee ing Web app cha ac e is ics, Web app de elopmen should use modula design o
inc ease changeabili y, main ainabili y, iendly use in e ace and connec i i y o ex e nal
en i ies. Based on he p elimina y and de ailed modula design, Web app main enance issues can
be dis ibu ed o ou s ages ha desc ibe as ollows:
Uni es ing p oblem: Change equency and schedule p essu e make uni es ing o en be
omi ed o dis ega ded. Incomple e uni es ing always causes p oblems and de ec s and
low o he ollow phases. Fo educing uni es ing isk, he uni es ing p ocedu e should be
clea ly de ined and au oma ed es ing ools need be sui ably applied [16], [20].
Sys em in eg a ion p oblem: based on so wa e sys em combined ela ion, ela ed uni
p og ams a e in eg a ed in o he unc ion modules, subsys ems and sys em. Lacking
au oma ed ools and p ocedu es, in eg a ion p ocess o en be delayed o no passed ha
causes e o s and de ec s low o he ollow de elopmen phases.
Communica ion p oblem: communica ion ba ie s be ween he use and de elope is he key
ac o o impac he success. Demo wo kable so wa e can inc ease common ecogni ion
be ween he use and de elope s [6], [7], [8]. In change eques s en i onmen , Web app
In e na ional Jou nal o So wa e Enginee ing & Applica ions (IJSEA), Vol.10, No.1, Janua y 2019
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should mee use eques s and imely elease new wo kable e sion o he use s o inc ease
us abili y. Howe e , i Web app canno imely elease new wo kable e sion, hen
communica ion ba ie s may expand and cause he de elopmen isk.
Quali y and e iciency p oblem: In Web app de elopmen and main enance p ocess, he e
a e many in e nal modules and ex e nal en i ies mus be in eg a ed. In e ace mis akes
always cause sys em p oblems and de ec s which deeply impac he quali y o so wa e
applica ion. Fo imp o ing applica ion quali y, he de elopmen ime mus be ex ended and
de elopmen budge mus be added. In e nal and ex e nal in e ace design o Web app is he
o he key de elopmen isk.
In eg a ion es ing ope a ions a e assigned o he es ing phase and no enough es equency. The
equency, ime and au oma ed ools o in eg a ion es ing a e c i ical eason o Web app
main enance p oblems. I is because he p oblems and de ec s canno be disco e y immedia ely
and cause he e o s ex ension o he ollow main enance ope a ion.
4. C
I
D
EVELOPMENT
E
NVIRONMENT
Fo achie ing he ea u es o CI, a CI en i onmen mus be build and he CI ope a ing p ocedu e
should be se up.
4.1 High quali y class componen
In o de o e ec i ely imp o e he ope a ional e iciency and quali y o CI, he de ini ion and
design o class componen s should ha e he ollowing quali y cha ac e is ics:
(1) Independence and modula i y:
App op ia e inhe i ance: The componen inhe i s he pa en class esou ce app op ia ely,
and he e ec o euse can be achie ed. Howe e , oo many le els o inhe i ance will cause
he componen o lose independence and modula i y.
High cohesion: Class componen s a e designed o be unc ional o in o ma ion cohesion,
which can imp o e he modula i y o he class componen s.
Low coupling: The coupling o da a o da a s uc u es can imp o e he modula i y o class
componen s.
(2) TDD-based uni es ing:
Comple e es cases: Be o e he de ail class design, he comple e es case mus be designed
acco ding o he class componen speci ica ions [17].
Combining wi h uni es ing ool: Uni es ing mus be able o ake au oma ed es ing o
uni es ing [22].
Assis an in eg a ion es ing: A comple e and clea in e ace design ha can help wi h
ongoing in eg a ion e o s.
(3) Main ainabili y:
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Changeabili y: In line wi h he con inuous e olu ion o he en i onmen and he cons an
changes in equi emen s, class componen s mus ha e ea u es ha a e easy o modi y and
adjus .
Ex ensibili y: In o de o imp o e he e iciency o main enance, he class componen s
should ha e he abili y o con inuously expand o inc ease he e iciency o main enance
ope a ion.
(4) In e ace in eg a ion abili y:
In e nal da a in eg a ion: In he p ocess o con inuous in eg a ion, in o de o compliance
he ope a ional p ocess and e iciency, he class componen s should e e o he exis ing
in e nal da a s uc u e in ad ance, and design an in e ace ha can be in eg a ed wi h he
in e nal da a s uc u e.
Ex e nal da a in eg a ion: In he con inuous expansion and in eg a ion p ocess, in o de o
compliance he ex e nal en i y ope a ion mode and da a o ma , he class componen s
should e e o he exis ing ex e nal en i y da a s uc u e in ad ance. And imely design he
in eg a ion in e ace wi h he ex e nal en i y da a s uc u e.
Using LCM (Linea Combina ion Model) [23], [24], ele an quali y ac o s o class componen
can be inco po a ed in o quali y me ics, hen ela ed quali y me ics can be inco po a ed in o
quali y measu emen s, and inally, quali y indica o o class componen can be gene a ed. The
quan i ied quali y measu emen combina ion p ocess is called a Class Componen Quali y
Measu emen (CCQM) Model (shown as igu e 2). Using CCQM can imely iden i y he quali y
de ec s o class componen , and conc e ely imp o e he quali y o class componen .
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Figu e 2. A chi ec u e o CCQM model
4.2
M
AJOR
F
EATURES
O
F
C
I
E
NVIRONMENT
In o de o quickly announce he wo kable so wa e, so wa e de elopmen en i onmen mus
combine high e iciency au oma ed ools and de elopmen p ocedu es. CI en i onmen should
connec wi h six majo ea u es o achie ing he wo kable so wa e o high quali y and high
e iciency. The majo componen s desc ibe as ollows (shown as igu e 3):
(1) Au oma ed es ing ools: Gene ally, ask o uni es ing belongs o he esponsibili y o
p og amme . A e coding, uni p og am needs p oceed comple e uni es ing. Pass he es
quali ied c i e ia, uni p og am can check-in o esou ce eposi o y o managing by CM
sys em. Fo imp o e uni es ing quali y and p oduc i i y, CI en i onmen should plan he
sui able and au oma ed uni es ing ools (ex. xUni , jUni ) o assis ing uni es ing
ope a ions o he p og amme [22].
(2) CM (Con igu e Managemen ) p ocedu e and e sion con ol: In o de o managemen
so wa e sys em a ious e sions, e sion con ol is necessa y ool o eco e y he p e ious
e sions and iden i y he e sion di e ence. In o de o moni o and con ol so wa e
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changes, CM p ocedu e is a necessa y sys em o eco d he e ision eason, da e,
p og amme and de ailed con en s. In o de o con inuously con ol and manage so wa e
sys em e sions, CM p ocedu e and e sion con ol ools (ex. gi , cs ) [25] a e he necessa y
componen o CI en i onmen .
(3) Sou ce eposi o y: A uni y eposi o y is an impo an communica ion channel o
de elopmen eam. The de elopmen documen s, sou ce code and ela ed documen s should
sa e o sou ce eposi o y o sha e by he s akeholde . Howe e , access secu i y o sou ce
eposi o y mus be ca e ully con olled and managed.
(4) Au oma ed in eg a ion: The modi ied, ex ended o upda ed sou ce codes need be
ecompiled, e es ed, and in eg a ed in o unc ion modules. Based on sa ed ime o ile,
module in eg a ion sc ip language can iden i y he new added o e ised sou ce codes and
en o ce compiling and linking in o unc ion module ope a ions. Acco ding o he in eg a ion
p ocedu e, a i s , module in eg a ion es ing need be execu ed and pass e i ica ion, and
hen subsys em in eg a ion es ing need be accomplished and pass e i ica ion. Finally,
based on sys em s uc u e, all subsys ems a e in eg a ed in o a sys em and has o be
accomplished es ing and e i ica ion.
(5) Au oma ed deploymen : A e sys em in eg a ion es , au oma ed deploymen is a nex
impo an s ep o quickly ins all new wo king so wa e on use si e. Au oma ed deploymen
can inc ease so wa e de elopmen e iciency and iden i y new wo kable so wa e e o s
and de ec s imely.
(6) P oblems and de ec s de ec o : iden i y he so wa e sys em p oblems and de ec s as ea ly as
possible, he e ision wo k can be simpli ied, modi ica ion e o can be educed. New
e sion so wa e accomplished deploying, he so wa e need p oceed comple e in e nal
e i ica ion and use alida ion. Based on he de ec ion p ocedu e, e i ica ion and
alida ion may iden i y he p oblems and de ec s o new e sion so wa e. Collec , analyse
and eco d he p oblems and de ec s, he co ec ion and e ision ope a ions should be
planned and execu ed as quickly as possible.
Figu e 3. CI En i onmen
