Solutions
Provider
for
FTTx,
RFoG
and
HFC
www.ascentcomtec.com
Page
34
of
114
source
server
sends
separate
copy
information
to
each
receiver.
When
a
large
number
of
users
require
this
information,
the
server
must
send
many
pieces
of
information
with
the
same
content
to
the
users.
Therefore,
large
bandwidth
will
be
occupied.
In
broadcast,
the
system
transmits
information
to
all
users
in
a
network.
Any
user
in
the
network
can
receive
the
information,
no
matter
the
information
is
needed
or
not.
Point
‐
to
‐
multipoint
multimedia
business,
such
as
video
conferences
and
VoD
(video
‐
on
‐
demand),
plays
an
important
part
in
the
information
transmission
field.
Suppose
a
point
to
multi
‐
point
service
is
required,
unicast
is
suitable
for
networks
with
sparsely
users,
whereas
broadcast
is
suitable
for
networks
with
densely
distributed
users.
When
the
number
of
users
requiring
this
information
is
not
certain,
unicast
and
broadcast
deliver
a
low
efficiency.
Multicast
solves
this
problem.
It
can
deliver
a
high
efficiency
to
send
data
in
the
point
to
multi
‐
point
service,
which
can
save
large
bandwidth
and
reduce
the
network
load.
Features
of
multicast
:
The
number
of
receivers
is
not
certain.
Usually
point
‐
to
‐
multipoint
transmission
is
needed;
Multiple
users
receiving
the
same
information
form
a
multicast
group.
The
multicast
information
sender
just
need
sends
the
information
to
the
network
device
once;
Each
user
can
join
and
leave
the
multicast
group
at
any
time;
Real
time
is
highly
demanded
and
certain
packets
drop
is
allowed.
Caution
：
A
multicast
source
does
not
necessarily
belong
to
a
multicast
group.
A
multicast
source
sends
data
to
a
multicast
group,
and
it
is
not
necessarily
a
receiver.
Multiple
multicast
sources
can
send
packets
to
the
same
multicast
group
at
the
same
time.
You
can
set
to
transmit
packets
with
multicast
destination
MAC
address
from
some
ports,
and
the
Static
Multicast
MAC
Address
Entries
List
will
be
displayed
at
the
bottom,
as
it
shows,
the
port
2
in
VLAN
1
can
forward
packets
to
the
multicast
MAC
01
‐
52
‐
65
‐
11
‐
32
‐
34
and
port
5
in
VLAN
2
can
forward
packets
to
multicast
MAC
01
‐
ac
‐
2b
‐
4e
‐
32
‐
55.
