Internati
o
nal
Journal of Ele
c
trical
and Computer
Engineering
(IJE
CE)
V
o
l.
6, N
o
. 1
,
Febr
u
a
r
y
201
6,
pp
. 29
2
~
29
7
I
S
SN
: 208
8-8
7
0
8
,
D
O
I
:
10.115
91
/ij
ece.v6
i
1.8
367
2
92
Jo
urn
a
l
h
o
me
pa
ge
: h
ttp
://iaesjo
u
r
na
l.com/
o
n
lin
e/ind
e
x.ph
p
/
IJECE
Analysis of Legacy System in Software Application
Development: A Comparative Survey
M. Sriniva
s
*
,
G. Ramakrish
n
a
*
,
K.
Ra
ja
sekha
ra
Ra
o
**
,
E. Sur
es
h Bab
u
*
*
D
e
p
a
rtm
e
nt
of
CS
E, K
L
EF
,
KL
University
,
AP
,
India
** Director, Sri
Prakash College
of Engin
eerin
g,
AP, India
Article Info
A
B
STRAC
T
Article histo
r
y:
Received
J
u
n 16, 2015
Rev
i
sed
No
v 9, 201
5
Accepted Nov 26, 2015
Software evo
l
ution is on
e of
the ch
allenging
issues in tod
a
y
’
s business
environment. It is necessar
y
f
o
r th
e organizations, which make use of
inform
ation,
an
d com
m
unicati
on technolog
ies
will have to
align their
bus
ines
s
proces
s
e
s
to com
p
ete with
global business. The ex
isting large
software s
y
st
em
s (“
legac
y
” s
y
st
em
s) have neve
r
been bu
ilt
to co
pe with th
e
current busin
ess requirement for
their
poor cod
i
ng, design structures, log
i
c
and documentation. Moreove
r
,
Legacy
app
lications have var
i
ou
s problems
such as lack of up to-date docu
m
enta
tion
,
skille
d m
a
n power, resources of
the Legacy
app
lications, and h
i
gh
mainten
a
nce costs.
Even
though th
e
Legacy
s
y
stem
is obsolete, it contai
ns detailed business rules and in
continuous use,
because i
t
satisfi
es th
e users'
ne
e
d
s and form
s the backbone
of the information flow of organization.
One of
the possible solutions is to
refac
t
or or m
o
derniz
e thos
e s
y
s
t
em
s
into a new platform
. It is
neces
s
a
r
y
to
anal
ys
e
the
exis
t
i
ng leg
a
c
y
s
y
s
t
e
m
fo
r better und
erstanding
the b
u
siness logic
and its function
a
lities.
This pap
e
r anal
y
s
es various techniqu
es
proposed for
understanding
Legacy
s
y
stems in
existence.
Keyword:
Business
Proce
s
s
Do
cu
m
e
n
t
atio
n
In
fo
rm
ation
Legacy system
s
Soft
ware
de
vel
opm
ent
Copyright ©
201
6 Institut
e
o
f
Ad
vanced
Engin
eer
ing and S
c
i
e
nce.
All rights re
se
rve
d
.
Co
rresp
ond
i
ng
Autho
r
:
M. Sr
i
n
iv
as,
Depa
rt
m
e
nt
of
C
o
m
put
er Sci
e
nce a
n
d
E
ngi
n
eeri
n
g,
K L Un
iv
ersity,
Gree
nfi
e
l
d
s, V
a
dde
swa
r
am
,
Gu
nt
u
r
Di
st
ri
ct
- 62
1
0
2
,
A
n
d
h
r
a
Pra
d
es
h, I
ndi
a.
Em
ail: srinu_c
se@kl
uni
verit
y
.in
1.
INTRODUCTION
Ove
r
t
h
e
l
a
st
t
w
o
deca
des,
l
e
gacy
sy
st
em
s [
1
]
are
one
o
f
t
h
e
busi
n
ess a
p
pl
i
cat
i
ons i
m
pl
em
ent
e
d i
n
m
o
st of t
h
e or
g
a
ni
sat
i
o
n
.
The
l
e
gacy
appl
i
cat
i
ons we
re de
ve
l
ope
d base
d o
n
t
echnol
ogi
es s
u
ch as m
a
i
n
fram
e
s,
SAP etc.,
whi
c
h continue
s to provid
e core services to an orga
nisa
tion. Recently, ther
e are
prominent
adva
nces i
n
technology, it is necessisary to
replace th
e le
gacy syste
m
s with the ne
w one
for the de
velopm
ent
o
f
bu
si
n
e
ss app
licatio
n
s
.
Howev
e
r, th
ere will b
e
so
m
e
o
f
th
e
o
p
e
ration
a
l risk
th
at may cau
se h
a
rm to
th
e
wh
ol
e sy
st
em
,
i
f
i
t
i
s
not
m
a
naged
pr
o
p
erl
y
.
Hence
,
t
h
ese s
y
st
em
s fi
nds di
ffi
cul
t
t
o
up
gra
d
e wi
t
h
t
h
e m
oder
n
t
echn
o
l
o
gy
. O
n
t
h
e
ot
her
ha
nd
, t
h
ere i
s
a
need t
o
ha
ve
efficient strate
gy
to re
f
actor [2] the system into
m
odern one.
Seve
ral approaches [3
] h
a
ve b
een
pr
opo
sed
to
tr
an
sf
orm
these legac
y
syste
m
s, which are
cl
assi
fi
ed i
n
t
o
rede
vel
o
pm
ent
,
wra
p
pi
n
g
, an
d m
i
grat
i
o
n
.
S
ubs
eq
ue
nt
l
y
, to t
r
ans
f
orm
t
h
ese sy
st
em
s ,t
here i
s
a
need to
unde
rs
tand a
n
d analy
s
e the ex
isting
legacy software syste
m
s. Ove
r
the years
,
m
a
ny resea
r
che
r
s
have
p
r
op
o
s
ed
v
a
ri
ou
s techn
i
qu
es t
o
an
alyse th
ese syste
m
s. In
ord
e
r t
o
un
derstan
d
t
h
e fu
nctio
nality o
f
th
e ex
i
s
tin
g
leg
acy syste
m
s
to
cop
e
up
with
th
e
current busi
n
ess require
m
ent
for a
pa
rticu
l
ar
d
o
m
ai
n
it is n
ecessary t
o
autom
a
te the legacy analysis process
t
o
re
d
u
ce t
i
m
e
and c
o
st
ef
fo
rt
s o
f
t
h
e o
r
gani
sat
i
o
n. T
h
i
s
pa
pe
r
hel
p
s t
o
u
n
d
e
rstand
b
e
tter th
e sign
ifican
ce an
d ch
allen
g
e
s
o
f
leg
acy
syste
m
s.
The R
e
st
of t
h
e pape
r i
s
or
ga
ni
sed as f
o
l
l
o
w
s
:
sect
i
on-
2 di
s
c
uss ab
o
u
t
si
g
n
i
f
i
cance
of l
e
gacy
sy
st
em
,
Sectio
n-3
g
i
v
e
s op
en
ch
alleng
es
o
f
leg
acy syste
m
s, a
n
d
sectio
n
-
4
illu
strates th
e wo
rk
d
o
n
e
so
far in
leg
acy
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
IJEC
E V
o
l
.
6, No
. 1, Feb
r
uar
y
20
1
6
:
29
2 – 29
7
29
3
sy
st
em
underst
a
ndi
ng
, sect
i
o
n-
5 i
s
abo
u
t
L
i
m
i
t
a
t
i
ons i
n
exi
s
t
i
ng t
ech
ni
q
u
es an
d sect
i
o
n-
6 ab
o
u
t
con
c
l
u
si
o
n
an
d fu
tur
e
w
o
rk
.
Fig
u
re
1
.
Ou
tlin
e
o
f
leg
acy sy
ste
m
2.
LEGAC
Y SY
STEM
SI
GN
I
F
IC
AN
CE
Leg
acy So
ftware system
s ar
e v
e
ry larg
e an
d
co
m
p
lex
as o
u
tlin
ed
in
fig
u
re-1
,
wh
ich
d
e
p
i
cts, t
h
e
soft
ware a
ppl
i
cat
i
ons de
vel
o
ped
usi
n
g So
f
t
ware t
o
ol
s th
at e
m
b
e
d
s
all
th
e b
u
s
in
ess ru
les related
t
o
th
e
b
u
s
i
n
ess pr
o
c
esses
of
an
o
r
g
a
n
i
zation
.
These
sof
t
w
a
r
e
ap
p
lication
s
p
r
o
cesses t
h
e
bu
sin
e
ss d
a
ta t
h
rough
com
put
er sy
st
em
s and
ge
ne
rat
e
s i
n
fo
rm
ati
on,
w
h
i
c
h
he
l
p
s t
h
e m
a
nagem
e
nt
t
o
achi
e
ve t
h
e
goa
l
s
an
d
o
b
j
ectiv
es
o
f
t
h
e org
a
n
i
sation
.
Th
e Leg
acy
so
ftware syste
m
s wh
ich
are b
u
ilt to
cop
e
u
p
with
th
e
n
e
ed
s of
b
u
s
i
n
ess org
a
nisatio
n
s
m
u
st
p
r
ov
id
e its fu
nctio
n
a
lity to
ru
n
th
e b
u
sin
e
ss
p
r
o
cesses in
a sm
o
o
t
h
m
a
n
n
e
r, and
sh
ou
l
d
afford
lo
ng
term
b
e
n
e
fits to
th
e cu
sto
m
ers.
Th
ese so
ft
ware syst
e
m
s e
m
b
e
d
d
e
d
with
all th
e d
a
ily
rou
tin
es
o
f
th
e o
r
g
a
n
i
satio
n.
Howev
e
r t
h
ese syste
m
s p
r
ov
i
d
es insufficient in
fo
rm
atio
n
to
th
e u
s
ers, and
th
ey
are not
user friendly. It is
diffic
u
lt to modi
fy and
replace the these
so
ftware
applications with latest
t
echn
o
l
o
gi
es.
M
o
re
ove
r, re
f
act
ori
n
g o
r
m
oderni
z
i
n
g Legacy
sy
st
em
s requi
res
,
B
u
si
ness P
r
ocesses
Reen
g
i
n
eeri
n
g
in
an
o
r
g
a
n
i
sat
i
o
n
.
Th
e
b
u
siness will be influ
e
n
c
ed
t
o
g
r
eater ex
ten
t
, if an
y ch
ang
e
o
r
failu
re
to that Le
gacy
syste
m
.
3.
MAJ
O
R OPE
N
CHALLENGE
S OF LEGACY
SYSTEMS
The Leg
acy
sy
st
em
s pose sev
e
ral
chal
l
e
nge
s
for e
x
ecut
i
ng
busi
n
ess
pr
oce
sses i
n
an o
r
ga
ni
sat
i
o
n
.
In
part
i
c
ul
a
r
a)
Legacy
sy
st
e
m
s are sl
ow
a
n
d
ex
pe
nsi
v
e
due
t
o
i
t
s
o
b
s
o
l
e
t
e
har
d
wa
re
b)
Main
ten
a
n
c
e
o
f
Leg
acy sy
ste
m
so
ftware is costly
be
cause
fa
ul
t
de
t
ect
i
on i
s
e
x
p
e
nsi
v
e
an
d t
i
me
co
nsu
m
in
g
d
u
e
i
m
p
r
op
er do
cumen
t
atio
n
,
lack
o
f
kno
wled
ge abo
u
t
fu
n
c
tion
a
lities o
f
th
e
syste
m
c)
Lack
of interfa
ces provide
s
g
r
eater d
i
fficu
lty to
in
teg
r
ate
wi
th
o
t
h
e
r systems.
d)
Evo
l
u
tion
o
f
l
e
g
acy system
s
to
p
r
ov
id
e
new fun
c
tion
a
lity requ
ired b
y
th
e
o
r
g
a
n
i
zatio
n
is v
i
rt
u
a
lly
im
possi
bl
e
This
pape
r a
n
a
l
yses the legac
y
syste
m
s. The analysis
of th
e leg
acy cod
e
help
s us to
so
lve th
e issu
es
suc
h
as u
p
g
ra
di
n
g
t
h
e l
e
gac
y
sy
st
em
, effect
i
v
e u
nde
rst
a
ndi
ng t
h
e
busi
n
ess
rul
e
s,
p
r
o
p
er
d
o
cum
e
nt
at
i
on f
o
r
t
h
e e
x
i
s
t
i
n
g
u
n
d
o
c
u
m
e
nt
ed
code
a
n
d
fi
nal
l
y
m
a
nagi
n
g
t
h
e
ri
p
p
l
e
ef
fec
t
. H
o
we
ve
r t
o
m
i
grat
e or
re
fact
or
,
m
a
i
n
t
a
i
n
i
ng a
nd
rew
r
i
t
i
ng
t
h
e exi
s
t
i
ng s
y
st
em
requi
re
s go
od
u
nde
r
s
t
a
ndi
ng
of t
h
e st
ruct
ure a
nd i
t
s
fun
c
tion
a
lity.
4.
REVIEW
O
N
LEGA
C
Y
S
Y
STEM
AN
AL
YSIS
Analysis of the legacy system
s he
lp
s to
und
erstan
d th
e ex
act situ
ation
o
f
t
h
e system
an
d its en
tire
pr
ocess
.
It
l
a
ys a great
fo
u
ndat
i
o
n f
o
r t
h
e furt
her de
ve
l
opm
ent
,
adva
ncem
ent
or sh
i
f
t
t
o
t
h
e adv
a
nced
technology.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Analysis of
Le
gacy
Sy
stem i
n
Software A
p
plication
Devel
opme
nt: A C
o
mpar
ative
Surve
y
(
M
. Sri
n
i
v
as)
29
4
Felix Cuadra
do et al [2] propos
ed
a t
ech
ni
que t
o
t
h
e rec
ove
ry
o
f
the legacy syste
m
architecture
w
h
ich
en
su
r
e
s
p
r
op
er do
cu
m
e
n
t
atio
n of
t
h
e l
e
g
acy syst
em
. Fo
r
b
e
tter
u
nderstand
ing
o
f
t
h
e leg
acy system
, th
e
Aut
h
o
r
has
e
x
t
r
act
ed
l
o
w-l
e
v
e
l
det
a
i
l
s
fr
om
con
f
i
g
urat
i
o
n
opt
i
o
ns
,
use
r
s
’
m
a
nual
a
n
d s
o
urce
c
ode
.
I
n
a
ddi
t
i
o
n
t
o
t
h
at
hi
g
h
-
l
e
vel
Det
a
i
l
s
acqui
red
fr
om
requi
rem
e
nt
s or desi
gn
d
o
cu
m
e
nt
s. He
use
d
Di
f
f
e
r
ent
t
o
ol
s f
o
r
reco
very
p
r
oce
ss, t
h
e
sel
ect
i
o
n
of
t
h
e
t
o
ol
d
e
pen
d
o
n
t
e
c
h
nol
ogi
es
, si
ze,
d
o
c
u
m
e
nt
at
i
o
n,
et
c.
T
h
e
p
r
o
pos
e
d
recov
e
ry techniq
u
e
u
tilizes t
h
e QAR im
p
l
e
m
en
t fo
r
do
cu
m
e
n
t
atio
n
analysis, static a
n
alysis an
d
d
y
n
a
m
i
c
an
alysis. Fo
r
Inform
atio
n
ex
traction
,
t
h
e
p
r
im
e resou
r
ce u
s
ed
is
u
s
er m
a
n
u
a
l.
Th
ey u
tilized
a
profilin
g
im
pl
em
ent
for
ext
r
act
i
n
g
ru
n
t
im
e i
n
form
at
ion
an
d
reve
rse
-
en
gi
nee
r
i
n
g i
m
pl
em
ent
s
l
i
k
e Ju
de a
n
d
O
m
ondo
UML
Stud
io t
o
ex
tract
th
e static v
i
ew of th
e
syste
m
, which
will au
t
o
matically an
alyz
e Jav
a
sou
r
ce
co
d
e
,
enge
nderi
ng
UML
class diagra
m
s
at class a
nd
pac
k
age
levels.
Th
e ab
ov
e i
m
p
l
e
m
en
t d
e
tects in
h
e
ritance an
d
d
e
p
e
nd
en
cy co
gn
ation
s
b
e
t
w
een elem
en
ts
.
The Jav
a
Pro
f
iler
of
TPTP
4
.
2
t
o
o
l
was
u
tilized
fo
r
Dyn
a
mic
anal
y
s
i
s
, w
h
i
c
h capt
u
res
ru
n
t
i
m
e
i
n
fo
rm
at
ion
-
m
e
t
hod i
n
v
o
cat
i
o
n
,
exec
ut
i
on t
i
m
e and n
u
m
b
er of i
n
st
ances i
n
recollection. Highe
r caliber a
r
chitectur
e was obt
ai
ne
d fr
om
t
h
e
abst
ract
i
o
n
pr
ocess whi
c
h
consi
s
t
s
of
a
s
e
ri
es
o
f
filtering
actio
n
s
.
Th
e an
alysis was ex
ecu
t
ed
cu
m
u
latin
g
b
o
t
h
th
e static an
d d
y
n
a
m
i
c s
y
ste
m
v
i
ews.
R
a
fi
k
A.
Sal
a
m
a
et
al
[3
]
pr
op
ose
d
a
m
ech
an
is
m
called
Mod
e
rn
izatio
n Strat
e
g
y
Selection
fram
e
work (M
SSF),
a
n
d Dec
i
sion
Ma
king
Tool,
whic
h a
n
alyses the
source
code t
o
m
easure
its quality. The
so
urce cod
e
selected
was m
easu
r
ed
u
s
ing
th
e CCCC API. Th
e au
tho
r
su
gg
ested
a
hyb
rid
m
o
d
e
rn
i
zatio
n
approach, for t
h
e organizations to e
v
aluate
each c
o
m
pone
nt vs
. service in a se
parate thread t
o
foc
u
s
on it
s
criteria’s value
s
alone
Saad
Al
a
h
m
a
ri et
al
[
4
]
p
r
op
ose
d
m
e
t
hod
ol
ogy
a
n
d e
f
fi
ca
ci
ous
g
u
i
d
el
i
n
es f
o
r
t
h
e i
d
e
n
t
i
f
i
cat
i
on
o
f
precise se
rvices from
legacy code
.
T
h
ey int
r
oduced Me
ta
m
o
d
e
l th
at d
e
fin
e
s th
e ch
aracteristics o
f
b
u
s
in
ess
pr
ocesses
a
n
d
servi
ces
t
y
pes.
The
a
p
p
r
oach
fi
xat
e
s
on
iden
tifyin
g
th
ese serv
ices
predi
cated
on a
Model
-
Dri
v
en
Arc
h
i
t
ect
ure a
p
p
r
oac
h
f
o
rt
i
f
i
e
d by
gui
del
i
n
es
ove
r a wi
de
ra
ng
e of
po
ssi
bl
e
servi
ces t
y
pes
.
They
accentuate
d
the im
portance
of t
h
e classific
a
tion of se
rvic
es types to de
fine their
prope
r
ties correctly
.
They
u
s
ed
UML
acti
v
ity d
i
agram
s
th
at id
en
tifies co
arse-g
rain
e
d
services
,
BPM
N
business
process diagram
s
were
adapt
e
d t
o
i
d
e
n
t
i
f
y
fi
ne
grai
ne
d se
rv
ices
, as
well as c
o
arse
-grai
n
ed service
s
. (as
c
o
m
posite service)
Grace
Le
wis
e
t
al [5]
use
d
SMAR
T
t
ool
to
analy
ze the
legacy com
p
onent
s
for
determ
ining c
h
a
nges
t
o
be m
a
de t
o
enabl
e
m
i
grat
i
on
of l
e
gacy
s
y
st
em
.
Thi
s
tool uses t
h
ree s
o
urces
of
info
rmatio
n
to
fo
rtify th
e
an
alysis activ
ity- First
Info
rmatio
n
cog
n
a
te t
o
th
e issues,
quan
d
a
ries t
h
at were
n
o
t
ed
b
y
the team
in
rev
e
l
a
tio
n
pr
ocess
,
sec
o
n
d
i
n
f
o
rm
at
i
on
pr
o
v
i
d
e
d
by
a
Ser
v
i
ce M
i
g
r
at
i
o
n
I
n
vent
ory
(
S
M
I
)
t
h
at
ext
r
act
t
h
e m
a
ny
d
e
si
red
b
e
h
a
v
i
or
o
f
serv
ices ex
ecu
ting
with
in
SOAs in
to
a
se
t of t
o
p
i
cs and
th
i
r
d sou
r
ce
of inform
at
io
n
en
tails th
e
u
tilizatio
n
o
f
co
d
e
an
alysis an
d arch
itecture recon
s
tru
c
tio
n too
l
s t
o
an
aly
ze th
e su
bsistin
g sou
r
ce co
de fo
r
legacy com
p
onents
Sm
i
t
h
, D et
al
[6]
pr
op
ose
d
a
SM
AR
T
t
ech
ni
que
wi
t
h
di
f
f
er
ent
be
ha
vi
or
w
h
i
c
h as
si
st
s o
r
gani
zat
i
o
ns
in
an
alyzin
g leg
acy cap
a
b
iliti
es for
u
s
e as serv
ices in
an
SOA
env
i
ronmen
t.
Th
e go
al of th
is activ
ity is to
obt
ai
n
desc
ri
pt
i
v
e dat
a
l
i
k
e t
h
e nam
e
, fu
nc
t
i
on, si
ze, l
a
n
g
u
age
,
o
p
e
r
at
i
n
g pl
at
f
o
rm
, an
d age
of t
h
e l
e
gacy
com
pone
nt
s t
h
at
are
c
onsi
d
er
ed
f
o
r
m
i
grat
i
on.
I
n
t
h
e
rec
o
v
e
ry
pr
ocess
,
A
r
chi
t
ect
ure
c
ode
, c
o
m
p
l
e
xi
t
y
d
e
si
gn
para
digm
s, level of
docum
e
ntation, c
o
upling, i
n
te
rfaces
, a
nd
de
pe
nde
nci
e
s betwee
n c
o
m
ponents e
x
tracted
fro
m
T
ech
n
i
cal p
e
rson
n
e
l.
In
ad
d
ition
,
the too
l
propo
se
s to
ex
tract informatio
n
related
t
o
q
u
a
lity
, m
a
tu
rity o
f
l
e
gacy
com
pon
ent
s
,
pr
obl
em
s, chan
ge
hi
st
ory
,
use
r
sat
i
s
fact
i
o
n
,
l
o
nge
r t
e
r
m
needs, c
o
st
f
o
r m
a
i
n
t
e
nanc
e an
d
finally ef
fort needed for these
analyses.
March
e
tto et
al propo
sed
[7
] an
app
r
o
a
ch
con
s
ists i
n
an
alyzin
g Legacy syste
m
app
licatio
n to
u
n
d
e
rstand
th
e syste
m
arch
itectu
r
e, and
id
entify th
e fu
n
c
tion
a
lities.
Th
ey
p
r
op
o
s
ed
m
ech
an
ism
to
reco
ver th
e
fun
c
tion
a
lities fro
m
tex
t
u
a
l u
s
e cases,
fun
c
tio
n
a
l
requ
isites in
n
a
t
u
ral lang
u
a
g
e
and
u
s
er
m
a
n
u
a
ls.
Th
ey h
a
ve
o
p
t
ed
t
o
represen
t th
e ap
p
licatio
n
fun
c
tion
a
l
ities an
d th
ei
r relatio
n
s
h
i
p
s
(e.g
., ex
tend
and
in
clu
d
e
) u
tilizin
g an
UML
Use Cas
e
diagram
.
When the
size of t
h
e a
pplicatio
n is
co
nsid
erab
le,
do
cu
m
e
n
t
atio
n
n
o
t
u
p
to
d
a
t
e
,
th
e
Aut
h
o
r
s
u
gge
st
ed R
e
verse
en
g
i
neeri
n
g t
e
c
hni
que
s t
o
re
prese
n
t
t
h
e a
r
c
h
i
t
ect
ure
o
f
t
h
e
ap
pl
i
cat
i
on.
Di
n
h
K
h
oa
N
g
uy
en
et
al
[
8
]
pr
o
pose
d
a
n
o
v
el
busi
n
e
ss se
rvi
c
e
en
gi
nee
r
i
n
g m
e
tho
d
o
l
o
gy
-
GAMB
U
SE
that identifies
and c
o
ncept
u
alizes busi
ness
serv
ices i
n
a bu
si
n
e
ss do
m
a
in
, is b
a
sed
o
n
a
stratified
refe
rence
Se
rv
ice M
e
ta-M
od
el (SM
M
)
that
speci
fies
an
d correlates all
m
o
d
e
lin
g
constru
c
ts
fo
r bu
sin
e
ss
processes
.
During t
h
is step,
the Se
rvice
Sc
hem
a
Speci
fications
(SS
S
)
o
f
the
as-i
s a
nd to-be
process
that
co
n
t
ain
t
h
eir activ
ities, b
u
s
i
n
ess en
tities, attribu
t
es, con
s
tr
ain
t
s, bu
sin
e
ss
ru
les, etc., are
in
stan
tiated
from th
e
SMM.
He
Y
u
an
H
u
an
g et
al
[9]
p
r
op
ose
d
ap
pr
oac
h
t
o
rec
o
g
n
i
ze t
h
e com
pone
nt
(s
) t
o
be re
use
d
,
eval
uat
e
t
h
e
depe
n
d
enci
es
on
ot
her
c
o
m
pone
nt
s,
ascert
a
i
n
t
h
e
de
pe
n
d
e
d
c
o
m
pone
nt
s
and
pr
od
uce
l
e
gacy
s
u
r
r
o
g
at
e
s
f
o
r
depe
n
d
ed
com
p
o
n
e
n
t
s
R
a
vi
Kha
d
a
e
t
al
pr
o
pose
d
t
w
o
[
10]
m
e
chani
s
m
s
.
On
e
of
t
h
em
i
s
reve
rse
en
gi
ne
eri
n
g
w
h
i
c
h
p
e
rf
or
m
s
its a
c
tio
n
s
b
y
under
s
tand
ing
an
d an
alyzin
g th
e sou
r
ce cod
e
. O
t
h
e
r
is
k
now
ledg
e
b
a
sed
w
h
ich
p
e
rform
s
its ac
tio
n
b
y
un
derst
a
n
d
i
n
g
th
e
kn
owledg
e
o
n
domain
an
d b
y
an
alyzin
g
t
h
e ex
p
e
rien
ce of the in
itial
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
IJEC
E V
o
l
.
6, No
. 1, Feb
r
uar
y
20
1
6
:
29
2 – 29
7
29
5
pr
om
ot
ers or
d
e
vel
o
pers
.
B
y
un
de
rst
a
n
d
i
n
g t
h
e
e
n
d
user
e
x
peri
e
n
ce wi
t
h
t
h
e hel
p
of
t
h
e
doc
um
ent
s
ava
i
l
a
bl
e
/ in
terv
iew
p
r
ocess,
o
n
e
can un
d
e
rstand
t
h
e a
pplications
of the legacy
system
s.
Vem
u
ri, P et
al [11] use
d
t
h
eory
of
Feature analysis to
detect th
e
features
from
a legacy system
wh
ich
id
en
tifies th
e k
e
y features of th
e leg
a
cy syste
m
fro
m
end-
users
,
t
h
e d
o
m
a
i
n
cognizance a
nd e
x
pertise
th
at ex
ists i
n
t
h
e leg
a
cy syste
m
tea
m
, to
Id
en
tify test
ca
ses from
the regres
sion
test su
ite
th
at represen
t
a
p
a
rticu
l
ar feat
u
r
e or a gr
oup of feat
u
r
es. Th
ey pro
p
o
s
ed
co
d
e
-p
ro
filing
i
m
p
l
e
m
en
ts
w
h
ich
produ
ce
i
n
tern
al
pr
o
duct
scri
pt
s
t
h
at
wo
ul
d t
r
a
ce t
h
e co
de t
r
a
v
ersal
pat
h
s a
n
d f
r
eq
ue
ncy
vi
a di
ffe
re
nt
m
odul
es a
nd
pac
k
ages o
f
th
e leg
acy
syste
m
, to
ex
ecu
te th
e test cases
id
en
tifie
d for e
ach
feature a
n
d acc
um
ulate the m
e
trics produce
d
by
t
h
e pr
o
f
i
l
i
ng im
pl
em
ent
s
. The m
e
t
r
i
c
s provi
de an
un
der
s
t
a
ndi
ng
of
un
-use
d areas
of
l
e
gacy
code
, l
e
vel
o
f
code
cat
chi
n
g
t
h
at
exi
s
t
s
i
n
t
h
e l
e
gacy
m
odul
es pe
r e
v
ery
fe
at
ure
Tabl
e
1. R
e
vi
e
w
of
u
n
d
e
rst
a
n
d
i
n
g a
n
d
anal
y
s
i
s
of
l
e
gacy
sy
st
em
S.no
Techniques
Specific
Tools /Models used
Refere
nce
1
Reverse Engineeri
ng, Architectural
Retr
ieval,
Docu
m
e
ntation,
User
's M
a
nual,
Static Anal
ysis,
D
y
na
m
i
c
Anal
ysis,
Generalization
QAR Jude and Om
ondo UM
L
Studio Java Pr
ofiler
of T
P
T
P
4.
2
Félix Cuadrado,
García
, nas,
&
Par
a
da,
200
2
Source code explora
tion
CCCC API
Rafik A. Sala
m
a
,
Sherif G. Al
y
3
M
odel T
r
ansform
a
tion,
Portfolio Analysis
I
n
ter
v
iewing,
Pr
ocess M
odelling,
Rever
s
e
E
ngineer
ing Questionnair
es
BPM
N
m
odel
Use case diagr
a
m
s
Analysis Model
SaadAlah
m
a
ri, Da
vid
De
Roure, Ed Z
a
luska
4
Architectural
Reco
nstruction
Docu
m
e
ntation,
Sour
ce Code E
xplor
ation,
,
I
nter
viewing
SMART
Tool
Grace
Lewis
et.al
5
Docu
m
e
ntation ,
Inter
v
iewing,
Sour
ce Code E
xplor
ation,
Ar
chitectu
r
al
Reconstr
uction
SM
ART T
ool
Grace
Lewis
et.al
2007
6
Rever
s
e E
ngineer
ing,
Docu
m
e
ntation,
Functional Requir
e
m
e
nts
Rever
s
e engineer
ing tools
Alessandr
o M
a
r
c
h
e
tto
7
Service Sche
m
a
S
p
ecif
i
cation
Service
M
e
ta-M
odel (
S
M
M
)
DinhKhoa Nguy
en et.
a
l
8
Sy
ste
m
reconstr
uction,
Docu
m
e
ntation,
Dyna
m
i
c Anal
ysis
Dependency
Analy
s
er
He Yuan Huang et
.al
9
Knowledge tr
ansfer
pr
ogr
am
s
,
M
odel-
Driven engineering Utilizing the hum
a
n
f
eedback
Rever
s
e E
ngineer
ing tool
s
Ravi Khadka et.
a
l
10
Test Cases,
Featur
e Analysis
code-prof
iling tool
s
Prasad Ve
m
u
ri
et.a
l
In s
u
m
m
ary
t
h
e Tabl
e-
1 gi
v
e
s com
p
l
e
t
e
underst
a
ndi
ng a
n
d anal
y
s
i
s
o
f
l
e
gacy
sy
st
em
pr
o
pose
d
by
vari
ous
resea
r
c
h
ers
.
The Fi
gure
2 depicts the iss
u
es of
Lega
cy syste
m
over the
spa
n
of
two
decades.
It is observe
d
tha
t
t
h
e doc
um
ent
a
t
i
on, sy
st
em
desi
gn re
q
u
i
r
em
ent
s
po
ses t
h
e chal
l
e
ng
es fo
r
t
h
e
m
a
i
n
t
e
nanc
e of Legacy
sy
st
em
.
From
t
h
e Fi
g
u
re i
t
i
s
al
so
ob
ser
v
e
d
t
h
a
t
t
y
pi
cal
sy
stem
desi
gn
,
p
o
o
r
doc
um
ent
a
t
i
on a
nd c
h
a
nge
i
n
requ
irem
en
ts effects th
e v
e
n
d
o
r
pro
d
u
c
t d
u
e
to
lack
o
f
u
pgrad
ation
.
Th
e Fig
u
re 3
illu
strates th
e co
m
p
arison
of va
ri
o
u
s
l
a
n
gua
ges use
d
t
o
devel
ope
d b
u
si
ness
ap
pl
i
c
at
i
ons wi
t
h
re
spect
t
o
so
ft
w
a
re
m
e
t
r
i
c
s
such
as
reusa
b
ility, cohesion, m
o
dularity, doc
um
entation a
nd c
o
m
p
lexity of m
e
thods
. It is
obse
r
ved t
h
a
t
the
language
s suc
h
as PA
SCAL
, COBOL
,
C,
CPPSC provid
es
m
o
re com
p
lex m
e
thods c
o
m
p
ared to the othe
r
m
odern l
a
ng
ua
ges s
u
c
h
as
J
A
VA
, J
S
C
,
.NE
T
A
N
D
P
H
P
.
Wh
en it co
m
e
s to
t
h
e
reusab
il
ity
m
e
tric leg
acy cod
e
in C, CPP,
and CPPSC
will have
m
o
re re
usa
b
le pe
rcent
a
ge tha
n
COB
O
L,
PASC
AL
. Further it is
also
obs
erved
from
the Figure tha
t
m
odul
arity and
docum
e
ntation m
e
trics in
JAVA, C, a
n
d
CPPSC will provi
de
b
e
tter an
alysis th
an
C
O
BOL,
PASC
AL and
.NET
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
Analysis of
Le
gacy
Sy
stem i
n
Software A
p
plication
Devel
opme
nt: A C
o
mpar
ative
Surve
y
(
M
. Sri
n
i
v
as)
29
6
Fi
gu
re
2.
Iss
u
e
s
i
n
Le
gacy
Sy
st
em
s
Fi
gu
re
3.
C
o
m
p
ari
s
i
o
n
o
f
l
a
n
gua
ges
vs
s
o
ft
ware
metrics
5.
LIMITATIONS IN E
X
IST
I
NG TE
CHNIQUES
Ove
r
the last few
decades
researche
r
s propos
ed
se
veral
techniques for understa
ndi
ng the legacy
syste
m
s ap
p
licatio
n
s
.
However, th
ere is n
e
cessity to
an
alyse these applications as
the
r
e
are som
e
issues and
challenges nee
d
to ans
w
e
r
for e
ffective managem
e
nt
of busi
n
ess pr
oce
sses
of or
ga
ni
zat
i
on.
S
u
bseq
uent
l
y
In
fo
rm
at
i
on ab
out
t
h
e
desi
g
n
,
archi
t
ect
u
r
e, i
t
s com
pone
nt
s,
i
n
t
e
r-
rel
a
t
i
ons
h
i
ps m
u
st
be car
eful
l
y
p
r
eser
ve
d s
o
th
at th
e leg
a
cy syste
m
s fu
nctio
n
s
work
s
effectiv
ely.
M
o
reov
er it is n
ecessary to
so
lv
e th
e
Kn
owledg
e
em
i
ssi
on
pr
ob
l
e
m
,
whi
c
h ca
n
be
o
v
erc
o
m
e
by
u
pdat
i
n
g
d
o
c
u
m
e
nt
at
i
o
n
fr
om
t
i
m
e
t
o
t
i
m
e, con
d
u
c
t
i
n
g
wo
rk
sh
o
p
s f
o
r
t
h
e expert
s i
n
or
de
r t
o
sol
v
e som
e
t
ech
ni
cal
i
ssues o
n
exi
s
t
i
n
g pr
o
g
ram
m
i
ng l
a
ngua
ges
.
Furt
her
m
o
re, t
h
e
reve
rse e
n
gi
neeri
n
g
t
ech
ni
que
s are
n
o
t
c
o
m
p
l
e
t
e
l
y
aut
o
m
a
t
e
d fo
r e
ffec
t
i
v
e m
a
nagem
e
nt
6.
CO
NCL
USI
O
N
AN
D F
U
T
U
RE W
O
R
K
Soft
ware e
vol
u
t
i
on i
s
one o
f
t
h
e chal
l
e
n
g
i
n
g
i
ssues i
n
t
oda
y
’
s busi
n
ess e
nvi
ro
nm
ent
.
It
i
s
necessary
for th
e
o
r
g
a
n
i
zatio
n
s
, wh
ich
mak
e
u
s
e of
In
fo
rm
atio
n
,
and
co
mm
u
n
i
cati
o
n techno
log
i
es will h
a
v
e
to
alig
n
their business
processes to c
o
m
p
ete
wi
t
h
gl
obal
b
u
si
nes
s
.
The exi
s
t
i
ng
large so
ftwa
re
sy
stem
s (“legacy
”
sy
st
em
s) have
neve
r b
een
bui
l
t
t
o
cope
wi
t
h
t
h
e cur
r
e
n
t
b
u
s
i
n
ess re
q
u
i
r
e
m
ent
for t
h
ei
r
po
o
r
co
di
n
g
,
d
e
si
gn
st
ruct
u
r
es,
l
o
g
i
c and
d
o
cu
m
e
nt
at
i
on.
In
t
h
i
s
pa
per
,
we a
n
al
y
s
ed
vari
ous
t
ech
ni
que
s p
r
op
ose
d
f
o
r
un
de
rst
a
n
d
i
n
g
Legacy
sy
st
em
s i
n
exi
s
t
e
nce
.
Su
bse
q
uent
l
y
, th
ere is a n
ecessity to
h
a
v
e
an
effectiv
e too
l
for
b
e
tter
u
n
d
e
rstan
d
i
n
g
an
d an
al
ysis o
f
leg
acy
syste
m
. In
ou
r
fu
tu
re work, we will
an
alyse Leg
acy Syste
m
s
u
s
ing
ANTLR
(An
o
t
h
e
r To
ol fo
r Lan
g
u
a
g
e
Reco
gn
itio
n) to
o
l
, wh
ich
is
p
r
o
-
d
o
m
in
an
t p
a
rser fo
r an
alysin
g,
studying, e
x
ec
uting a
n
d trans
l
ation of
bina
ry or text files.
The key as
pec
t
s of ANTLR
,
accepts large c
l
ass of
gram
m
a
rs and
bui
l
d
s t
h
e
par
s
e t
r
ees f
o
r a
gi
ven i
n
put
pr
o
g
r
am
. Event
u
al
l
y
, i
t
i
s
m
o
re w
o
rt
h f
u
l
l
i
f
A
N
TLR
i
s
in
teg
r
ated
with
m
u
lti-th
readin
g
env
i
ro
n
m
en
t th
at creat
es m
u
lt
ip
le in
stan
ces
wh
ich
tak
e
s m
u
ltip
le files as
in
pu
t and
prov
i
d
e effectiv
e outp
u
t
s
for
b
e
tter
an
alysis of legacy syste
m
s
REFERE
NC
ES
[1]
Yang
H., Zhan
Cui, O
'
Brien,
P.
“E
xtracting
onto
l
ogies from lega
cy system
s for u
nderstanding an
d re engin
eering
”,
Com
puter Software and
Applic
at
ions Conferenc
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,
1999.
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ceed
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y
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i
rd Annua
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tiona
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erenc
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[2]
Moeini A.
Raf
e
V.,
Mahdian F. “An
appr
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advanced Comp
uter Theory and
Engineering (
I
CACTE)
, 2010 3rd
International Conference
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Date 20-22
Aug. 2010
[3]
Asil A.
Almonaies,
James R.
Cordy
,
and
Thom
as
R. De
an.
“
L
e
g
ac
y S
y
s
t
em
Ev
olution
towards
S
e
rvice-Ori
e
nt
e
d
Archite
cture
”
,
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ternational Wor
k
shop on SOA M
i
gration and
Evo
l
ution
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2010).
[4]
Cuadrado, F.,
García, B., Duenas
, J., & Parada, H.A. (2008)
. “
A Case Study on Software Evolution towards
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e-Orient
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d
Archite
ctur
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onal Conf
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n
Networking and
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Workshops
[5]
Salama, R
.,
&
Aly
,
S.G. (2008
). “
A Decision
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r the Selecti
on
of Service Oriented-Based Leg
a
cy
Systems Modern
ization Strategies
”. P
a
per
pres
en
ted
at
the
The
I
n
terna
tiona
l Con
f
erenc
e
on
S
o
ft
ware Eng
i
ne
erin
g
Res
earch
and
P
r
act
ice
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Veg
a
s
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Alahmari, S.,
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010). “
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e
c
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ci
en
t
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ica
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es on Serv
ice-Orien
t
ed
Ent
e
rprise Archit
ec
t
u
re
”. P
a
p
e
r pr
es
ented
at
the
P
r
oceed
ings
of th
e
2010 14th I
EEE Intern
ation
a
l
Enterprise Distrib
u
ted Obj
ect Co
mputing Confer
ence
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, D
C
,
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[7]
Lewis, G., Morris, E., & Smith,
D. (2006). “
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l
yzing th
e Reuse Poten
tial o
f
Migrating Legacy
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a
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v
ic
e-Or
ient
e
d
Ar
chi
t
ec
tur
e
”. Paper pr
esented at the 10th
Eu
ropean
Conf
eren
ce on
S
o
ftware
M
a
inten
a
nce
an
d
Reengin
eering
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C
MSR'
06).
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S
SN
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088
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08
IJEC
E V
o
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r
uar
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20
1
6
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29
7
[8]
Lewis G., & Smith D.B. (2007). “
Developing
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migration of lega
cy components t
o
s
e
r
v
ice-or
i
e
nted
ar
chitec
t
ur
e en
vir
onments
”, Paper presented at the 2ndintern
a
tional conf
eren
ce on Trends in
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i
s
e
appli
c
ation
arch
it
ectur
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[9]
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.
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008). “
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a
n
equiva
len
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e
b-services based
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a
rd a tool suppo
rted stepwise approach
”. Paper
presented at the
10th Internation
a
l S
y
mposium o
n
Web Site Evolu
t
ion (WSE'
08)
.
[10]
Ngu
y
en D., van
den Heuvel W.J
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, Papazog
l
ou M., de C
a
st
ro V.,
& Marcos E. (2
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is
m
e
thodolog
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onceptu
al
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ons and Applications, 293-
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[11]
Huang H.Y., Tan H.F., Zhu J., & Zhao W. (2008). “
A Lig
h
tweight Appro
a
ch to
Partiall
y Reuse Ex
istin
g
Component-Based System in Se
rvice-Orien
t
ed Environment
”. P
a
per pres
ent
e
d a
t
the
10thinternational conferen
ce
on Software Reu
s
e: High Conf
id
ence Software
R
e
use in
L
a
rge
S
y
stem
s, Berlin
, H
e
ide
l
berg.
[12]
Ravi Khadk
a
et
al,
“
Leg
a
c
y
to
S
OA Evolution
:
A S
y
s
t
em
at
ic
Li
t
e
ratur
e
R
e
view”
[13]
Vemuri, P. (200
8,” Modern
izing
a leg
acy
s
y
s
t
em t
o
SOA - Fe
a
t
ure a
n
aly
s
i
s
approa
c
h
.”
Pa
pe
r pre
s
e
n
te
d at
t
h
e
TENCON 2008
- 2008 IEEE Region 10 Conf
erence.
BIOGRAP
HI
ES OF
AUTH
ORS
M.
Srinivas received his MCA from IGNOU,
New Delhi
and M.
Tech.
d
egree in Computer
Science and En
gineer
ing from Achar
y
a Nagar
j
una
University
and presently
pur
suing the Ph.D.
in K L
Universit
y
,
Guntur (Dist)
,
AP, India
.
He
is
working pres
en
t
l
y
as
an As
s
o
ciat
e profes
s
o
r in
the dep
a
rtment
of computer science
and
Engin
eering
in KLUn
iversity
.He is h
a
ving 19
y
e
ars
Experience
in
Teaching in r
e
puted institutio
ns
. His research interests in
clude Software
Engineering, Datamining. He
is
life member of
professional bod
ies lik
e CSI, ISTE. He
taught
various subjects
in computer scien
ce and engi
neering lik
e software engin
eering, computer
organization
,
Database Manag
e
me
nt s
y
stems, Cr
yptograph
y
and n
e
twork secu
rity
,
Digital Log
i
c
design, UML ,O
OPS etc.
Dr. Ram
a
kris
hn
a Gavirn
eni
curr
entl
y working
as
Professor in department
of CSE KLUniversity
,
Vaddeswaram
. Carried out r
e
search at Sah
a
Institu
te, Cal
c
utt
a
fo
r about five and
half
y
ears from
1966-1971 in theoretical ph
y
s
ics
using computers at
ISI, Calcutta, IIT Khargapur
, IIT Kanpur, &
IITMadras exten
s
ively
for solvin
g problems in n
u
clear models and Obtained Ph.D. in 1975. He
carried out R & D and execu
ted
several pro
j
ects at ECIL, H
y
der
a
bad from 1975 to 2003.Was
train
e
d on the
s
t
ate of art s
o
ft
ware for S
upervisor
y
Control
&Data Acquisition (SCADA)
Software Pipelin
e Leak De
te
ctio
n Software
at LOGICA,
LOND
ON,
UK in 198
3 Designed for
ECIL a 2D Gra
phics
S
o
ftware
P
ackage for
P
r
i
n
te
d circuit boar
d
lay
out
at National Cen
t
re for
Software Develo
pment & Com
puting Techniqu
es (NCSDCT), TIFR, Bombay
fr
om 1975-1977.
Also he dev
e
lop
e
d models (usin
g
computers) for
analy
s
is of
lens design
at NIT,
Warangal which
have b
een
used
in the dep
t
. of Ph
y
s
ics
to
carr
y
ou
t R & D Projects.
Prof. Kurra Rajasekhara Rao is
a Professor of
C
o
mputer Science & Engineer
ing and presently
working as Director
, Sri Prakash College of
Engineer
ing (SPCE), Tuni.
He worked at
KLCE/K.
L
.
U
niversity
for 20
y
e
ars as a faculty
member in various positions as HOD of C
S
E,
HOD of
IT,Vice-Princip
a
l, Prin
cipal, K L Co
llege of Engineer
ing
(Autonomo
u
s), and Dean
(Adm
inistration)
, Dean (Facult
y
& Student Affairs) Dean (Exams
& Evaluation) of KLU. He i
s
having m
o
re tha
n
30+
years
of
t
each
ing and r
e
s
e
arch exp
e
ri
enc
e
,
P
r
of. KRR is
ac
tivel
y
engag
e
d
in th
e rese
arc
h
rel
a
ted
to
Em
bedded S
y
s
t
ems, Software Engin
eering
and Knowledg
e
Management. He had ob
tain
ed
Ph.D in Co
mputer Science
& Engin
eering
from Achar
y
a
Nagarjuna University
(ANU),
Gunt
ur,
A.
P.
under the able guidance of Prof.
P
.
T
hrimurthy
.
He
published more
than 80
pap
e
rs in various In
tern
ation
a
l/National
Journals and Co
nferences. H
e
produced 4
Ph.D
s and
he
is member
of
IETE, INSCA, IEI,ISTE,CSI
Mr. E. Suresh
Babu receiv
ed h
i
s B.Tech degr
ee in Computer
Science from RGM College of
Engineering, Nand
y
a
l, M.Tech
d
e
gree
in Com
put
er S
c
ien
c
e
from
V.T. Univ
ers
i
t
y
Belgaum
and
pursuing PhD in Computer Science & Eng
i
neer
i
ng from J.
N.
T.
U
n
ive
r
sity
K
a
kinada. Curr
ently
,
he is
working
as
an As
s
o
ciate P
r
ofes
s
o
r in
the Departm
e
nt
of CS
E in
K L Univers
i
t
y
Vijay
a
wad
a
; He has 12
y
ears o
f
teaching
exper
i
ence. He h
a
s published 8 research papers in
various International Journal
a
nd 6 research
papers in
var
i
o
u
s National
an
d Intern
ation
a
l
Conferences. He has attend
ed 3
2
seminars and workshops. His
ar
eas of interests are wireless
communication
and MANETs, S
ecur
ity
, Mobile
Sensor Networks.
Evaluation Warning : The document was created with Spire.PDF for Python.