<s>
Basic	B-Device
Interoperable	I-Device
Scrambling	I-Device
System	I-Device
,	O
usually	O
known	O
as	O
BISS	B-Device
,	O
is	O
a	O
satellite	B-Application
signal	O
scrambling	O
system	O
developed	O
by	O
the	O
European	O
Broadcasting	O
Union	O
and	O
a	O
consortium	O
of	O
hardware	O
manufacturers	O
.	O
</s>
<s>
Prior	O
to	O
its	O
development	O
,	O
"	O
ad	O
hoc	O
"	O
or	O
"	O
occasional	O
use	O
"	O
satellite	B-Application
news	O
feeds	O
were	O
transmitted	O
either	O
using	O
proprietary	O
encryption	O
methods	O
(	O
e.g.	O
</s>
<s>
RAS	O
,	O
or	O
PowerVu	B-Device
)	O
,	O
or	O
without	O
any	O
encryption	O
.	O
</s>
<s>
Unencrypted	O
satellite	B-Application
feeds	O
allowed	O
anyone	O
with	O
the	O
correct	O
equipment	O
to	O
view	O
the	O
program	O
material	O
.	O
</s>
<s>
Proprietary	O
encryption	O
methods	O
were	O
determined	O
by	O
encoder	O
manufacturers	O
,	O
and	O
placed	O
major	O
compatibility	O
limitations	O
on	O
the	O
type	O
of	O
satellite	B-Application
receiver	O
(	O
IRD	O
)	O
that	O
could	O
be	O
used	O
for	O
each	O
feed	O
.	O
</s>
<s>
BISS	B-Device
was	O
an	O
attempt	O
to	O
create	O
an	O
"	O
open	O
platform	O
"	O
encryption	O
system	O
,	O
which	O
could	O
be	O
used	O
across	O
a	O
range	O
of	O
manufacturers	O
equipment	O
.	O
</s>
<s>
There	O
are	O
mainly	O
two	O
different	O
types	O
of	O
BISS	B-Device
encryption	O
used	O
:	O
</s>
<s>
BISS-1	O
transmissions	O
are	O
protected	O
by	O
a	O
12	O
digit	O
hexadecimal	O
"	O
session	O
key	O
"	O
that	O
is	O
agreed	O
by	O
the	O
transmitting	O
and	O
receiving	O
parties	O
prior	O
to	O
transmission	O
.	O
</s>
<s>
The	O
key	O
is	O
entered	O
into	O
both	O
the	O
encoder	O
and	O
decoder	O
,	O
this	O
key	O
then	O
forms	O
part	O
of	O
the	O
encryption	O
of	O
the	O
digital	O
TV	O
signal	O
and	O
any	O
receiver	O
with	O
BISS-support	O
with	O
the	O
correct	O
key	O
will	O
decrypt	O
the	O
signal	O
.	O
</s>
<s>
BISS-E	O
(	O
E	O
for	O
encrypted	O
)	O
is	O
a	O
variation	O
where	O
the	O
decoder	O
has	O
stored	O
one	O
secret	O
BISS-key	O
entered	O
by	O
for	O
example	O
a	O
rights	O
holder	O
.	O
</s>
<s>
This	O
session	O
key	O
is	O
then	O
mathematically	O
combined	O
internally	O
to	O
calculate	O
a	O
BISS-1	O
key	O
that	O
can	O
decrypt	O
the	O
signal	O
.	O
</s>
<s>
Only	O
a	O
decoder	O
with	O
the	O
correct	O
secret	O
BISS-key	O
will	O
be	O
able	O
to	O
decrypt	O
a	O
BISS-E	O
feed	O
.	O
</s>
<s>
Any	O
BISS-E	O
encrypted	O
feed	O
will	O
have	O
a	O
corresponding	O
BISS-1	O
key	O
that	O
will	O
unlock	O
it	O
.	O
</s>
<s>
BISS-E	O
is	O
amongst	O
others	O
used	O
by	O
EBU	O
to	O
protect	O
UEFA	O
Champions	O
League	O
and	O
other	O
high-profile	O
satellite	B-Application
feeds	O
.	O
</s>
