Optik
125 (2014) 657–
662
Contents
lists
available
at
ScienceDirect
Optik
jou
rn
al
homepage:
www.elsevier.de/ijleo
A
new
green
multicast
grooming
protection
algorithm
in
WDM
optical
networks
Cunqian
Yu,
Yejun
Liu
∗
,
Weigang
Hou,
Yao
Yu,
Jingjing
Wu,
Peipei
Jiang
College
of
Information
Science
and
Engineering,
Northeastern
University,
Shenyang
110819,
China
a
r
t
i
c
l
e
i
n
f
o
Article
history:
Received
27
February
2013
Accepted
1
July
2013
Keywords:
Optical
network
Green
multicast
grooming
Protection
Spanning
path
a
b
s
t
r
a
c
t
Since
optical
network
carries
a
lot
of
traffic,
survivability
is
very
important
to
ensure
the
service
continuity
against
network
failures.
Recently,
multicast
services
become
more
popular
to
meet
the
huge
multimedia
demand
in
network,
so
that
multicast
survivability
in
optical
network
has
got
more
attention.
However,
multicast
survivability
may
lead
to
more
energy
consumption
due
to
more
redundant
backup
resources
allocated.
Since
greening
network
is
particularly
important
with
the
energy
crisis
keeping
growing,
green
multicast
survivability
in
optical
network
is
a
challenging
issue.
This
paper
focuses
on
the
green
multicast
grooming
protection
problem
in
optical
network
and
designs
two
auxiliary
graphs
that
includes
a
vir-
tual
topology
graph
and
an
integrated
graph
to
address
the
survivable
multicast
grooming,
routing
and
wavelength
assignment.
Based
on
the
auxiliary
graphs,
this
paper
proposes
an
efficient
heuristic
called
green
multicast
grooming
algorithm
based
on
spanning
path
dedicated
protection
(GMG-SPDP),
in
which
the
network
reliability
and
the
energy
efficiency
are
jointly
taken
into
account.
Simulation
results
show
that,
compared
to
other
algorithms,
the
proposed
GMG-SPDP
not
only
has
lower
blocking
probability
and
higher
bandwidth
utilization
ratio,
but
also
saves
more
energy.
© 2013 Elsevier GmbH. All rights reserved.
1.
Introduction
Internet
traffic
is
growing
fast
[1].
Fortunately,
optical
switching
plays
an
important
role,
especially
for
the
highly-bandwidth
and
super-data-rate
service
provisioning,
in
the
wavelength-division-
multiplexing
(WDM)
transmission
systems.
Yet
the
fiber
failure
may
cause
serious
damage
to
the
normal
communications
and
the
huge
data
loss.
The
survivability
of
WDM
optical
networks
has
gained
extensive
attentions
[2–4].
Furthermore,
various
multicast
applications,
such
as
VOD,
online
game,
etc.,
are
increasing
and
provide
unprecedented
facility.
Therefore,
the
multicast
protec-
tion
becomes
a
hotspot
in
the
field
of
optical
network
survivability
[5].
On
the
other
hand,
the
energy
consumption
of
information
com-
munication
technology
(ICT)
has
been
responsible
for
up
to
10%
of
the
total
energy
consumption
and
2%
of
the
global
carbon
emis-
sions
in
the
world
[6].
“Being
green”
is
particularly
urgent
for
the
routing
of
multicast
protection
currently,
and
the
green
grooming
is
an
alternative
option
in
terms
of
traffic
engineering.
Grooming
is
to
aggregate
new
demands
into
built-lightpaths,
if
the
available
band-
width
of
built-lightpaths
is
enough.
Compared
with
no-grooming,
∗
Corresponding
author
at:
P.O.
Box
365,
College
of
Information
Science
and
Engi-
neering,
Northeastern
University,
Shenyang
110819,
China.
Tel.:
+86
24
83684219;
fax:
+86
24
83684219.
E-mail
addresses:
liuyejun09@gmail.com,
haveball@hotmail.com
(Y.
Liu).
it
occupies
less
fibers,
transceivers,
ports
of
routers
and
ampli-
fiers,
so
it
will
consume
less
energy.
Therefore,
it
motivates
us
to
integrate
green
grooming
with
the
multicast
protection
strategy
in
green
and
survivable
optical
networks.
As
shown
in
Fig.
1,
two
multicast
demands
have
built
two
light-trees,
i.e.,
T
1
(7–8–9–6)
and
T
2
(3–4–5–9–1).
The
demand
3
directly
adopts
T
1
.
The
demand
4
builds
a
new
light-tree
T
3
(2–7–1),
as
no
built
lightpath
can
be
trav-
eled.
The
demand
5
extends
a
branch
based
on
T
2
,
who
splits
the
optical
signal
at
node
5
and
sends
it
to
node
6.
The
demands
3
and
5
are
groomed
into
the
built
light-trees
and
they
utilize
the
rest
resource
in
built
light-trees,
resulting
in
energy
saving.
Conventional
strategies
of
the
multicast
protection
include
tree-
based
protection
[7],
segment-based
protection
and
path-based
protection
[8].
Shown
as
Fig.
2,
here
is
a
multicast
demand
from
5
to
(1,
2,
4),
and
its
primary
light-tree
(called
working
tree
in
this
paper)
comprises
fiber
links
(5–0),
(0–1),
(1–2)
and
(0–4).
In
Fig.
2(a),
following
tree-based
protection
approach,
we
found
a
backup
light-tree
(called
protection
tree
in
this
paper).
Since
tree-
based
protection
requires
all
fiber
links
in
protection-tree
to
be
link-disjoint
with
the
working-tree,
its
computation
complexity
is
very
high
[7].
In
Fig.
2(b),
following
segment-based
protec-
tion
approach,
we
found
four
protection
paths
for
four
segments,
respectively.
Its
computation
complexity
is
lower,
but
it
occu-
pied
much
bandwidth
and
more
transceivers
and
ports.
Finally,
in
Fig.
2(c)
following
path-based
protection,
we
just
need
two
protec-
tion
paths.
It
takes
only
three
links
and
6
transceivers
for
protection
and
link
(0–3)
is
totally
idle.
0030-4026/$
–
see
front
matter ©
2013 Elsevier GmbH. All rights reserved.
http://dx.doi.org/10.1016/j.ijleo.2013.07.073