<s>
RMCDE	B-General_Concept
(	O
SuRveillance	O
Message	O
Conversion	O
and	O
Distribution	O
Equipment	O
)	O
is	O
the	O
name	O
of	O
a	O
system	O
designed	O
to	O
distribute	O
the	O
surveillance	O
information	O
to	O
a	O
community	O
of	O
user	O
systems	O
.	O
</s>
<s>
A	O
user	O
of	O
surveillance	O
data	O
in	O
a	O
general	O
sense	O
is	O
defined	O
in	O
this	O
context	O
as	O
any	O
Air	B-Application
Traffic	I-Application
Control	I-Application
(	O
ATC	O
)	O
subsystem	O
having	O
a	O
requirement	O
to	O
receive	O
at	O
defined	O
instants	O
the	O
best	O
and	O
most	O
up-to-date	O
position	O
information	O
for	O
all	O
air	B-Application
traffic	I-Application
of	O
interest	O
to	O
this	O
user	O
(	O
e.g.	O
</s>
<s>
radar	B-Application
,	O
ADS-B	B-Application
receiver	O
,	O
Multi-lateration	O
system	O
)	O
or	O
a	O
surveillance	O
data	O
processing	O
system	O
(	O
e.g.	O
</s>
<s>
RMCDE	B-General_Concept
is	O
a	O
Multibus	O
II	O
based	O
multiprocessor	O
system	O
composed	O
of	O
a	O
number	O
of	O
subsystems	O
(	O
processor	O
and	O
IO	O
boards	O
)	O
connected	O
through	O
a	O
parallel	O
data	O
bus	O
.	O
</s>
<s>
In	O
addition	O
to	O
its	O
distribution	O
function	O
,	O
the	O
RMCDE	B-General_Concept
offers	O
additional	O
capabilities	O
to	O
manage	O
the	O
surveillance	O
data	O
flow	O
like	O
data	O
validation	O
,	O
conversion	O
and	O
filtering	O
.	O
</s>
<s>
Until	O
1990	O
,	O
each	O
ATC	O
centre	O
was	O
serviced	O
by	O
a	O
dedicated	O
set	O
of	O
(	O
local	O
)	O
radars	B-Application
.	O
</s>
<s>
Radar	B-Application
data	O
exchange	O
was	O
only	O
done	O
at	O
a	O
limited	O
scale	O
,	O
one	O
of	O
the	O
reasons	O
being	O
that	O
the	O
sensors	O
were	O
using	O
proprietary	O
,	O
incompatible	O
formats	O
.	O
</s>
<s>
In	O
April	O
1990	O
,	O
the	O
Ministers	O
of	O
Transport	O
of	O
the	O
European	O
Civil	O
Aviation	O
Conference	O
(	O
ECAC	O
)	O
launched	O
the	O
"	O
En-route	O
Strategy	O
for	O
the	O
1990s	O
"	O
-	O
a	O
multilateral	O
strategy	O
designed	O
to	O
ensure	O
that	O
,	O
by	O
the	O
end	O
of	O
the	O
century	O
,	O
Air	B-Application
Traffic	I-Application
Control	I-Application
capacity	O
will	O
match	O
forecasted	O
demand	O
.	O
</s>
<s>
This	O
strategy	O
drove	O
an	O
initial	O
programme	O
,	O
EATCHIP	O
-	O
the	O
European	O
ATC	O
Harmonisation	O
and	O
Integration	O
Programme	O
,	O
developed	O
and	O
managed	O
by	O
Eurocontrol	O
to	O
undertake	O
the	O
progressive	O
harmonisation	O
and	O
integration	O
of	O
Air	B-Application
Traffic	I-Application
Services	O
throughout	O
the	O
ECAC	O
area	O
.	O
</s>
<s>
The	O
main	O
component	O
in	O
RADNET	O
is	O
the	O
RMCDE	B-General_Concept
.	O
</s>
<s>
The	O
RMCDE	B-General_Concept
is	O
one	O
of	O
the	O
first	O
systems	O
in	O
the	O
ATC	O
domain	O
that	O
provided	O
what	O
now	O
would	O
be	O
called	O
publish/subscribe	O
services	O
.	O
</s>
<s>
Each	O
user	O
connected	O
to	O
RADNET	O
can	O
subscribe	O
to	O
surveillance	O
data	O
provided	O
by	O
any	O
of	O
the	O
other	O
RMCDEs	B-General_Concept
in	O
the	O
network	O
.	O
</s>
<s>
In	O
order	O
to	O
cope	O
with	O
the	O
limited	O
bandwidth	O
of	O
network	O
connections	O
in	O
those	O
days	O
,	O
the	O
RMCDE	B-General_Concept
allows	O
filtering	O
and	O
merging	O
on	O
the	O
source	O
node	O
,	O
so	O
that	O
only	O
data	O
which	O
is	O
of	O
real	O
interest	O
is	O
sent	O
across	O
the	O
network	O
.	O
</s>
<s>
In	O
an	O
ATC	O
centre	O
the	O
RMCDE	B-General_Concept
is	O
used	O
as	O
a	O
front-end	O
processor	O
(	O
i.e.	O
</s>
<s>
The	O
RADNET/RMCDE	O
combination	O
is	O
not	O
only	O
a	O
new	O
technology	O
that	O
was	O
introduced	O
for	O
surveillance	O
data	O
exchange	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
technology	O
,	O
a	O
common	O
implementation	O
approach	O
was	O
developed	O
,	O
radar	B-Application
sharing	O
agreements	O
were	O
drafted	O
between	O
states	O
and	O
EUROCONTROL	O
established	O
an	O
organisational	O
unit	O
that	O
was	O
responsible	O
for	O
the	O
day-to-day	O
support	O
of	O
both	O
the	O
technological	O
as	O
well	O
as	O
the	O
organisational	O
aspects	O
.	O
</s>
<s>
Amsterdam	O
,	O
Brussels	O
,	O
Düsseldorf	O
and	O
Bremen	O
)	O
,	O
more	O
than	O
100	O
RMCDEs	B-General_Concept
have	O
been	O
deployed	O
in	O
the	O
ATC	O
infrastructures	O
of	O
18	O
Eurocontrol	O
member	O
states	O
.	O
</s>
