<s>
In	O
systems	O
management	O
,	O
out-of-band	B-Application
management	I-Application
involves	O
the	O
use	O
of	O
management	O
interfaces	O
(	O
or	O
serial	B-Protocol
ports	I-Protocol
)	O
for	O
managing	O
networking	B-Device
equipment	I-Device
.	O
</s>
<s>
Cellular	O
4G	O
and	O
5G	O
networks	O
are	O
used	O
today	O
for	O
out-of-band	B-Application
management	I-Application
and	O
many	O
manufacturers	O
have	O
it	O
as	O
a	O
product	O
offering	O
.	O
</s>
<s>
Out-of-band	B-Application
management	I-Application
is	O
now	O
considered	O
an	O
essential	O
network	O
component	O
to	O
ensure	O
business	O
continuity	O
.	O
</s>
<s>
Out-of-band	B-Application
management	I-Application
allows	O
the	O
network	O
operator	O
to	O
establish	O
trust	O
boundaries	O
in	O
accessing	O
the	O
management	O
function	O
to	O
apply	O
it	O
to	O
network	O
resources	O
.	O
</s>
<s>
In	O
computing	O
,	O
one	O
form	O
of	O
out-of-band	B-Application
management	I-Application
is	O
sometimes	O
called	O
lights-out	B-Application
management	I-Application
(	O
LOM	O
)	O
and	O
involves	O
the	O
use	O
of	O
a	O
dedicated	O
management	O
channel	O
for	O
device	O
maintenance	O
.	O
</s>
<s>
By	O
contrast	O
,	O
in-band	O
management	O
through	O
VNC	B-Protocol
or	O
SSH	B-Protocol
is	O
based	O
on	O
in-band	O
connectivity	O
(	O
the	O
usual	O
network	O
channel	O
)	O
.	O
</s>
<s>
Both	O
in-band	O
and	O
out-of-band	B-Application
management	I-Application
are	O
usually	O
done	O
through	O
a	O
network	O
connection	O
,	O
but	O
an	O
out-of-band	B-Application
management	I-Application
card	O
can	O
use	O
a	O
physically	O
separated	O
network	O
connector	O
if	O
preferred	O
.	O
</s>
<s>
)	O
;	O
broadcasting	O
of	O
video	O
output	O
to	O
remote	O
terminals	O
and	O
receiving	O
of	O
input	O
from	O
remote	O
keyboard	O
and	O
mouse	O
(	O
KVM	B-Application
over	O
IP	O
)	O
.	O
</s>
<s>
It	O
also	O
can	O
access	O
local	O
media	O
like	O
a	O
DVD	O
drive	O
,	O
or	O
disk	B-Application
images	I-Application
,	O
from	O
the	O
remote	O
machine	O
.	O
</s>
<s>
Settings	O
for	O
hardware	O
RAID	B-Architecture
or	O
RAM	B-Architecture
timings	O
can	O
also	O
be	O
adjusted	O
as	O
the	O
management	O
card	O
needs	O
no	O
hard	O
drives	O
or	O
main	O
memory	O
to	O
operate	O
.	O
</s>
<s>
As	O
management	O
via	O
serial	B-Protocol
port	I-Protocol
has	O
traditionally	O
been	O
important	O
on	O
servers	O
,	O
a	O
complete	O
remote	O
management	O
system	O
also	O
allows	O
interfacing	O
with	O
the	O
server	O
through	O
a	O
serial	O
over	O
LAN	O
cable	O
.	O
</s>
<s>
As	O
sending	O
monitor	O
output	O
through	O
the	O
network	O
is	O
bandwidth	O
intensive	O
,	O
cards	O
like	O
AMI	O
's	O
MegaRAC	O
use	O
built-in	O
video	O
compression	O
(	O
versions	O
of	O
VNC	B-Protocol
are	O
often	O
used	O
in	O
implementing	O
this	O
)	O
.	O
</s>
<s>
The	O
remote	O
system	O
can	O
be	O
accessed	O
either	O
through	O
an	O
SSH	B-Protocol
command-line	O
interface	O
,	O
specialized	O
client	O
software	O
,	O
or	O
through	O
various	O
web-browser-based	O
solutions	O
.	O
</s>
<s>
Internally	O
,	O
Ethernet-based	O
out-of-band	B-Application
management	I-Application
can	O
either	O
use	O
a	O
dedicated	O
separate	O
Ethernet	O
connection	O
,	O
or	O
some	O
kind	O
of	O
traffic	O
multiplexing	O
can	O
be	O
performed	O
on	O
the	O
system	O
's	O
regular	O
Ethernet	O
connection	O
.	O
</s>
<s>
That	O
way	O
,	O
a	O
common	O
Ethernet	O
connection	O
becomes	O
shared	O
between	O
the	O
computer	O
's	O
operating	O
system	O
and	O
the	O
integrated	O
baseboard	B-Device
management	I-Device
controller	I-Device
(	O
BMC	O
)	O
,	O
usually	O
by	O
configuring	O
the	O
network	B-Protocol
interface	I-Protocol
controller	I-Protocol
(	O
NIC	O
)	O
to	O
perform	O
Remote	O
Management	O
Control	O
Protocol	O
(	O
RMCP	O
)	O
ports	O
filtering	O
,	O
use	O
a	O
separate	O
MAC	O
address	O
,	O
or	O
to	O
use	O
a	O
virtual	B-General_Concept
LAN	I-General_Concept
(	O
VLAN	B-General_Concept
)	O
.	O
</s>
<s>
An	O
older	O
version	O
of	O
out-of-band	B-Application
management	I-Application
is	O
a	O
layout	O
involving	O
the	O
availability	O
of	O
a	O
separate	O
network	O
that	O
allows	O
network	O
administrators	O
to	O
get	O
command-line	O
interface	O
access	O
over	O
the	O
console	B-Protocol
ports	I-Protocol
of	O
network	B-Device
equipment	I-Device
,	O
even	O
when	O
those	O
devices	O
are	O
not	O
forwarding	O
any	O
payload	O
traffic	O
.	O
</s>
<s>
If	O
a	O
location	O
has	O
several	O
network	B-Device
devices	I-Device
,	O
a	O
terminal	B-Device
server	I-Device
can	O
provide	O
access	O
to	O
different	O
console	B-Protocol
ports	I-Protocol
for	O
direct	O
CLI	O
access	O
.	O
</s>
<s>
In	O
case	O
there	O
is	O
only	O
one	O
or	O
just	O
a	O
few	O
network	B-Device
devices	I-Device
,	O
some	O
of	O
them	O
provide	O
AUX	O
ports	O
making	O
it	O
possible	O
to	O
connect	O
a	O
dial-in	O
modem	O
for	O
direct	O
CLI	O
access	O
.	O
</s>
<s>
The	O
mentioned	O
terminal	B-Device
server	I-Device
can	O
often	O
be	O
accessed	O
via	O
a	O
separate	O
network	O
that	O
does	O
not	O
use	O
managed	O
switches	O
and	O
routers	O
for	O
a	O
connection	O
to	O
the	O
central	O
site	O
,	O
or	O
it	O
has	O
a	O
modem	O
connected	O
via	O
dial-in	O
access	O
through	O
POTS	O
or	O
ISDN	B-Protocol
.	O
</s>
