<s>
Enigma2	O
,	O
the	O
second	O
generation	O
of	O
Enigma	B-Application
software	O
,	O
is	O
an	O
application	B-Application
used	O
in	O
Linux-based	O
Digital	B-Application
Video	I-Application
Broadcasting	I-Application
(	O
DVB-S	O
,	O
DVB-C	B-Device
,	O
DVB-T	O
)	O
receivers	B-Device
or	O
TV	O
set-top	O
boxes	O
and	O
Internet	O
Protocol	O
television	O
receivers	B-Device
.	O
</s>
<s>
It	O
creates	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
to	O
control	O
the	O
said	O
devices	O
using	O
a	O
remote	B-Protocol
control	I-Protocol
and	O
provides	O
features	O
such	O
as	O
tuning	O
available	O
satellite	O
transponders	O
,	O
cable	O
channels	O
and	O
terrestrial	O
television	O
transmitters	O
(	O
according	O
to	O
available	O
tuners	B-Device
)	O
or	O
accessing	O
material	O
via	O
Internet	O
Protocol	O
television	O
(	O
IPTV	O
)	O
,	O
watching	O
a	O
TV	O
program	O
or	O
listening	O
to	O
radio	O
,	O
time	B-Device
shifting	I-Device
,	O
Digital	B-Application
video	I-Application
recorder	I-Application
,	O
streaming	O
media	O
programs	O
to	O
other	O
devices	O
(	O
personal	B-Device
computer	I-Device
,	O
mobile	O
phone	O
)	O
,	O
etc	O
.	O
</s>
<s>
Other	O
features	O
are	O
available	O
through	O
plugins	O
–	O
for	O
example	O
Electronic	B-Device
program	I-Device
guide	I-Device
(	O
EPG	B-Device
)	O
,	O
Hybrid	B-Device
Broadcast	I-Device
Broadband	I-Device
TV	I-Device
(	O
HbbTV	B-Device
)	O
,	O
access	O
to	O
TV	O
archives	O
and	O
movie	O
databases	O
,	O
playback	O
of	O
multimedia	O
files	O
,	O
viewing	O
photos	O
,	O
etc	O
.	O
</s>
<s>
The	O
name	O
Enigma2	O
is	O
often	O
used	O
to	O
refer	O
to	O
the	O
whole	O
Linux	B-Application
distribution	I-Application
designed	O
for	O
TV	O
receivers	B-Device
containing	O
the	O
Enigma2	O
application	B-Application
.	O
</s>
<s>
Sometimes	O
the	O
distribution	O
is	O
called	O
Linux	B-Application
E2	O
or	O
E2	O
Linux	B-Application
,	O
but	O
usually	O
it	O
is	O
named	O
after	O
the	O
specific	O
distro	B-Application
or	O
development	O
team	O
–	O
OpenATV	O
,	O
OpenPLi	O
,	O
OpenViX	O
,	O
EGAMI	O
,	O
OpenEight	O
,	O
Black	O
Hole	O
,	O
OpenDroid	O
,	O
PurE2	O
,	O
etc	O
.	O
</s>
<s>
The	O
distribution	O
was	O
originally	O
developed	O
for	O
Dreambox	B-Operating_System
receivers	B-Device
,	O
but	O
after	O
2010	O
a	O
number	O
of	O
manufacturers	O
of	O
similar	O
equipment	O
appeared	O
,	O
such	O
as	O
Formuler	O
,	O
GigaBlue	O
,	O
Octagon	O
,	O
Opticum	O
,	O
Unibox	B-Device
,	O
Vu+	B-Application
,	O
Zgemma	O
,	O
etc	O
.	O
</s>
<s>
satellite	O
receivers	B-Device
,	O
set-top	O
boxes	O
and	O
IPTV	O
receivers	B-Device
,	O
often	O
simply	O
called	O
boxes	O
)	O
are	O
equipped	O
with	O
one	O
or	O
more	O
DVB-S	O
,	O
DVB-C	B-Device
and	O
DVB-T	O
tuner(s )	O
(	O
unless	O
they	O
are	O
pure	O
IPTV	O
receivers	B-Device
)	O
,	O
a	O
Remote	B-Protocol
control	I-Protocol
receiver	B-Device
and	O
an	O
Ethernet	O
and/or	O
Wi-Fi	O
network	O
adapter	O
.	O
</s>
<s>
The	O
operating	O
system	O
is	O
usually	O
stored	O
on	O
internal	O
flash	O
memory	O
,	O
whereas	O
to	O
record	O
programs	O
or	O
to	O
play	O
multimedia	O
files	O
a	O
larger	O
,	O
internal	O
or	O
external	O
,	O
hard	B-Device
disk	I-Device
,	O
SSD	B-Device
,	O
USB	O
flash	O
disk	O
or	O
memory	O
card	O
can	O
be	O
used	O
.	O
</s>
<s>
The	O
device	O
may	O
use	O
Network	B-Application
Attached	I-Application
Storage	I-Application
or	O
a	O
disk	O
volume	O
on	O
a	O
personal	B-Device
computer	I-Device
using	O
Samba	B-Language
or	O
NFS	B-Protocol
protocol	I-Protocol
as	O
well	O
.	O
</s>
<s>
The	O
system	O
is	O
designed	O
to	O
be	O
controlled	O
by	O
a	O
Remote	B-Protocol
control	I-Protocol
similar	O
to	O
those	O
used	O
for	O
TV	O
receivers	B-Device
.	O
</s>
<s>
The	O
TV	O
set	O
usually	O
connected	O
via	O
a	O
HDMI	B-Protocol
(	O
or	O
SCART	B-Protocol
)	O
cable	O
works	O
as	O
a	O
multimedia	O
monitor	O
.	O
</s>
<s>
The	O
device	O
may	O
connect	O
to	O
a	O
home	O
audio	O
system	O
either	O
via	O
TOSLINK	B-Protocol
or	O
Bluetooth	B-Protocol
.	O
</s>
<s>
The	O
box	O
can	O
be	O
accessed	O
with	O
terminal	B-Application
emulation	I-Application
protocol	O
telnet	B-Protocol
,	O
ssh	B-Protocol
,	O
or	O
via	O
FTP	B-Protocol
.	O
</s>
<s>
The	O
box	O
can	O
act	O
as	O
a	O
streaming	O
server	O
,	O
streaming	O
material	O
received	O
by	O
its	O
tuners	B-Device
or	O
direct	O
from	O
its	O
hard	B-Device
drive	I-Device
or	O
any	O
mounted	O
device	O
available	O
to	O
it	O
.	O
</s>
<s>
Enigma	B-Application
is	O
one	O
of	O
the	O
Graphical	B-Application
user	I-Application
interfaces	I-Application
developed	O
for	O
digital	O
satellite	O
receivers	B-Device
DBox-2	B-Application
during	O
the	O
TuxBox	O
project	O
in	O
2000-2001	O
.	O
</s>
<s>
The	O
development	O
was	O
then	O
continued	O
by	O
Dream	B-Operating_System
Multimedia	I-Operating_System
for	O
their	O
receivers	B-Device
.	O
</s>
<s>
In	O
2006	O
Dream	B-Operating_System
Multimedia	I-Operating_System
released	O
a	O
new	O
open	B-License
source	I-License
version	O
of	O
the	O
software	O
called	O
enigma2	O
.	O
</s>
<s>
Around	O
that	O
time	O
many	O
receiver	B-Device
manufacturers	O
who	O
were	O
competitors	O
of	O
Dream	B-Operating_System
Multimedia	I-Operating_System
started	O
using	O
the	O
software	O
developed	O
by	O
Dream	B-Operating_System
Multimedia	I-Operating_System
without	O
contributing	O
to	O
system	O
development	O
.	O
</s>
<s>
Dream	B-Operating_System
Multimedia	I-Operating_System
therefore	O
decided	O
not	O
to	O
continue	O
system	O
development	O
as	O
free	B-Application
software	I-Application
and	O
introduced	O
its	O
own	O
Dreambox	B-Operating_System
OS	O
.	O
</s>
<s>
Currently	O
,	O
there	O
are	O
about	O
20	O
teams	O
that	O
develop	O
the	O
enigma2	O
application	B-Application
,	O
control	O
and	O
maintain	O
their	O
own	O
versions	O
of	O
the	O
distribution	O
for	O
dozens	O
types	O
of	O
devices	O
.	O
</s>
<s>
The	O
main	O
feature	O
is	O
displaying	O
the	O
received	O
TV	O
program	O
on	O
the	O
TV	O
screen	O
connected	O
usually	O
using	O
an	O
HDMI	B-Protocol
cable	O
transferring	O
sound	O
as	O
well	O
.	O
</s>
<s>
At	O
the	O
same	O
time	O
Enigma2	O
creates	O
graphical	B-Application
user	I-Application
interface	I-Application
controlled	O
using	O
an	O
infrared	O
remote	O
commander	O
,	O
that	O
displays	O
on	O
the	O
TV	O
screen	O
in	O
the	O
form	O
of	O
menu	O
,	O
dialogues	O
and	O
forms	O
allowing	O
control	O
of	O
all	O
basic	O
settings	O
of	O
the	O
set-top	O
box	O
or	O
the	O
receiver	B-Device
.	O
</s>
<s>
Some	O
plugins	O
appear	O
in	O
the	O
Plugins	O
menu	O
and	O
can	O
be	O
customised	O
from	O
there	O
while	O
others	O
blend	O
seamlessly	O
into	O
the	O
graphical	B-Application
user	I-Application
interface	I-Application
in	O
such	O
a	O
way	O
that	O
it	O
is	O
not	O
always	O
clear	O
what	O
is	O
a	O
plugin	O
and	O
what	O
is	O
a	O
built	O
in	O
feature	O
.	O
</s>
<s>
And	O
,	O
depending	O
on	O
the	O
distro	B-Application
,	O
some	O
plugins	O
are	O
built	O
into	O
the	O
base	O
distribution	O
,	O
for	O
example	O
,	O
Graphical	O
EPG	B-Device
and	O
AutoTimer	O
recordings	O
.	O
</s>
<s>
To	O
use	O
an	O
Enigma2	O
box	O
as	O
a	O
Digital	B-Application
video	I-Application
recorder	I-Application
,	O
or	O
for	O
time	B-Device
shifting	I-Device
or	O
other	O
features	O
like	O
system	O
backup	O
and	O
setup	O
it	O
is	O
possible	O
to	O
connect	O
an	O
external	O
hard	B-Device
disk	I-Device
or	O
USB	O
flash	O
drive	O
.	O
</s>
<s>
Some	O
receivers	B-Device
contains	O
a	O
builtin	O
disk	O
or	O
have	O
a	O
pull-out	O
drawer	O
to	O
install	O
an	O
internal	O
hard	B-Device
disk	I-Device
drive	I-Device
.	O
</s>
<s>
Also	O
use	O
of	O
network-attached	B-Application
storage	I-Application
or	O
a	O
shared	O
disk	O
from	O
a	O
computer	O
is	O
possible	O
.	O
</s>
<s>
For	O
Internet	O
access	O
,	O
access	O
to	O
network	O
disk	O
storages	O
or	O
to	O
shared	O
folders	O
on	O
computer	O
,	O
stream	O
programs	O
to	O
a	O
computer	O
,	O
mobile	O
phone	O
or	O
other	O
receiver	B-Device
and	O
to	O
control	O
the	O
receiver	B-Device
from	O
a	O
computer	O
using	O
web	O
browser	O
,	O
or	O
other	O
purposes	O
most	O
receivers	B-Device
have	O
builtin	O
interface	O
Ethernet	O
and/or	O
Wi-Fi	O
,	O
or	O
it	O
is	O
possible	O
to	O
connect	O
an	O
external	O
WiFi	O
module	O
.	O
</s>
<s>
The	O
receiver	B-Device
uses	O
DHCP	B-Protocol
for	O
dynamic	O
assignment	O
of	O
IP	B-Protocol
address	I-Protocol
,	O
but	O
when	O
the	O
user	O
wants	O
to	O
control	O
receiver	B-Device
using	O
web	O
browser	O
,	O
file	B-Protocol
transfer	I-Protocol
protocols	I-Protocol
File	B-Protocol
Transfer	I-Protocol
Protocol	I-Protocol
(	O
FTP	B-Protocol
)	O
or	O
SFTP	B-Protocol
or	O
to	O
login	O
interactively	O
to	O
the	O
receiver	B-Device
using	O
telnet	B-Protocol
or	O
SSH	B-Protocol
,	O
it	O
is	O
better	O
to	O
configure	O
the	O
receiver	B-Device
to	O
use	O
a	O
fixed	O
IP	B-Protocol
address	I-Protocol
.	O
</s>
<s>
Enigma	B-Application
2	O
boxes	O
are	O
equipped	O
with	O
interfaces	O
for	O
popular	O
conditional	O
access	O
cards	O
like	O
Common	B-Device
Interface	I-Device
slot	O
and/or	O
smart	O
card	O
reader	O
to	O
allow	O
reception	O
of	O
encrypted	O
content	O
which	O
may	O
be	O
stored	O
or	O
streamed	O
after	O
decryption	O
.	O
</s>
<s>
It	O
contains	O
a	O
virtual	O
remote	B-Protocol
control	I-Protocol
offering	O
the	O
same	O
features	O
as	O
remote	B-Protocol
control	I-Protocol
supplied	O
with	O
the	O
receiver	B-Device
.	O
</s>
<s>
Use	O
of	O
this	O
interface	O
must	O
be	O
enabled	O
in	O
receiver	B-Device
settings	O
and	O
an	O
access	O
password	O
must	O
be	O
generated	O
.	O
</s>
<s>
Connection	O
to	O
the	O
receiver	B-Device
is	O
usually	O
possible	O
only	O
from	O
within	O
the	O
LAN	O
network	O
as	O
most	O
internet	O
providers	O
assign	O
IP	B-Protocol
addresses	I-Protocol
dynamically	O
and	O
do	O
not	O
allow	O
connecting	O
from	O
the	O
public	O
internet	O
to	O
home	O
network	O
.	O
</s>
<s>
By	O
clicking	O
to	O
the	O
screen	O
icon	O
or	O
mobile	O
phone	O
icon	O
next	O
to	O
the	O
desired	O
program	O
or	O
multimedia	O
file	O
,	O
a	O
*	O
.m3u	O
stream	O
is	O
opened	O
that	O
can	O
be	O
reproduced	O
by	O
VLC	B-Application
or	O
any	O
other	O
application	B-Application
that	O
is	O
compatible	O
with	O
the	O
selected	O
source	O
.	O
</s>
<s>
Cheaper	O
receivers	B-Device
with	O
single	O
tuner	B-Device
allow	O
streaming	O
,	O
recording	O
and	O
watching	O
programs	O
from	O
only	O
one	O
multiplex	B-Device
or	O
satellite	O
transponder	O
at	O
a	O
time	O
.	O
</s>
<s>
Many	O
boxes	O
have	O
multiple	O
tuners	B-Device
which	O
allows	O
streaming	O
,	O
watching	O
or	O
recording	O
programs	O
from	O
more	O
than	O
one	O
multiplex	B-Device
or	O
satellite	O
transponder	O
simultaneously	O
.	O
</s>
<s>
The	O
latest	O
boxes	O
rather	O
that	O
having	O
multiple	O
tuners	B-Device
have	O
a	O
newer	O
type	O
of	O
tuner	B-Device
module	O
known	O
as	O
Full	O
Band	O
Capture	O
which	O
allow	O
up	O
to	O
8	O
multiplexes	B-Device
to	O
be	O
tuned	O
simultaneously	O
,	O
per	O
tuner	B-Device
module	O
.	O
</s>
<s>
When	O
there	O
are	O
not	O
enough	O
tuners	B-Device
for	O
the	O
current	O
demand	O
,	O
recordings	O
take	O
priority	O
,	O
so	O
while	O
recording	O
a	O
program	O
on	O
single-tuner	O
box	O
it	O
is	O
not	O
possible	O
to	O
switch	O
to	O
channels	O
on	O
other	O
multiplexes	B-Device
or	O
transponders	O
and	O
even	O
while	O
watching	O
a	O
program	O
the	O
receiver	B-Device
may	O
automatically	O
switch	O
to	O
another	O
program	O
when	O
a	O
programmed	O
recording	O
starts	O
.	O
</s>
<s>
Each	O
distro	B-Application
has	O
its	O
own	O
feeds	O
available	O
from	O
the	O
internet	O
via	O
the	O
network	O
adaptor	O
.	O
</s>
<s>
Package	O
management	O
and	O
versioning	O
is	O
handled	O
by	O
opkg	B-Application
.	O
</s>
<s>
When	O
a	O
new	O
version	O
or	O
build	O
is	O
available	O
an	O
icon	O
is	O
displayed	O
in	O
the	O
graphical	B-Application
user	I-Application
interface	I-Application
to	O
alert	O
the	O
user	O
.	O
</s>
<s>
Enigma2	O
allows	O
backing	O
up	O
the	O
system	O
to	O
an	O
attached	O
disk	O
or	O
network-attached	B-Application
storage	I-Application
.	O
</s>
<s>
Some	O
receivers	B-Device
allow	O
installing	O
on	O
the	O
internal	O
volume	O
a	O
number	O
of	O
different	O
system	O
images	O
(	O
usually	O
max	O
.	O
</s>
<s>
This	O
feature	O
is	O
useful	O
to	O
evaluate	O
different	O
disk	O
images	O
,	O
either	O
different	O
versions	O
or	O
from	O
different	O
teams	O
,	O
and	O
in	O
case	O
of	O
problems	O
with	O
the	O
receiver	B-Device
(	O
allows	O
distinguishing	O
between	O
hardware	O
and	O
software	O
problems	O
)	O
.	O
</s>
<s>
The	O
receiver	B-Device
can	O
also	O
be	O
reflashed	O
to	O
a	O
different	O
operating	O
system	O
or	O
system	O
version	O
using	O
USB	O
disk	O
or	O
SD/SDHC	O
card	O
.	O
</s>
<s>
The	O
look	O
of	O
the	O
enigma2	O
application	B-Application
in	O
most	O
distributions	O
is	O
widely	O
configurable	O
.	O
</s>
<s>
Selecting	O
the	O
skin	O
is	O
done	O
from	O
the	O
menu	O
and	O
after	O
a	O
GUI	B-Application
restart	O
the	O
new	O
skin	O
is	O
displayed	O
.	O
</s>
<s>
Pro	O
File	O
transfer	O
between	O
receiver	B-Device
and	O
computer	O
in	O
home	O
network	O
is	O
possible	O
using	O
protocols	O
FTP	B-Protocol
,	O
SFTP	B-Protocol
or	O
shared	O
directory	O
trees	O
in	O
receiver	B-Device
using	O
protocols	O
Samba	B-Language
or	O
Network	B-Protocol
File	I-Protocol
System	I-Protocol
(	O
NFS	B-Protocol
)	O
.	O
</s>
<s>
Downloading	O
multimedia	O
files	O
from	O
receiver	B-Device
to	O
a	O
computer	O
can	O
be	O
performed	O
using	O
OpenWebif	O
interface	O
as	O
well	O
.	O
</s>
<s>
It	O
is	O
possible	O
to	O
connect	O
to	O
the	O
enigma2	O
box	O
using	O
terminal	B-Application
emulator	I-Application
protocol	O
telnet	B-Protocol
or	O
SSH	B-Protocol
.	O
</s>
<s>
A	O
password	O
must	O
be	O
generated	O
either	O
using	O
the	O
GUI	B-Application
or	O
SSH	B-Protocol
.	O
</s>
<s>
After	O
login	O
the	O
user	O
gets	O
to	O
the	O
Linux	B-Application
Command-line	B-Application
interface	I-Application
,	O
and	O
therefore	O
some	O
knowledge	O
this	O
environment	O
and	O
some	O
specialties	O
of	O
E2	O
Linux	B-Application
systems	O
is	O
necessary	O
.	O
</s>
<s>
This	O
access	O
is	O
rather	O
a	O
supplement	O
that	O
is	O
allowed	O
by	O
using	O
system	O
Linux	B-Application
,	O
as	O
greater	O
part	O
of	O
necessary	O
features	O
is	O
realized	O
using	O
the	O
enigma2	O
GUI	B-Application
application	B-Application
or	O
by	O
plugins	O
.	O
</s>
<s>
Enigma2	O
application	B-Application
implements	O
a	O
Graphical	B-Application
user	I-Application
interface	I-Application
(	O
GUI	B-Application
)	O
to	O
control	O
DVB	B-Application
receivers	B-Device
;	O
it	O
does	O
not	O
use	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
for	O
graphic	O
output	O
as	O
is	O
usual	O
on	O
Linux	B-Application
systems	O
,	O
but	O
direct	O
access	O
to	O
framebuffer	B-Algorithm
;	O
to	O
run	O
it	O
makes	O
use	O
the	O
Linux	B-Application
kernel	O
and	O
environment	O
,	O
usually	O
in	O
lightweight	O
versions	O
(	O
BusyBox	B-Application
,	O
Dropbear	B-Protocol
(	O
software	O
)	O
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
for	O
software	O
build	O
OpenEmbedded	B-Application
(	O
OE	O
)	O
environment	O
is	O
used	O
.	O
</s>
<s>
The	O
Enigma2	O
core	O
is	O
written	O
in	O
the	O
programming	O
language	O
C++	B-Language
and	O
creates	O
an	O
API	B-General_Concept
for	O
plugins	O
written	O
in	O
Python	B-Language
(	O
programming	O
language	O
)	O
.	O
</s>
