<s>
A	O
message	B-General_Concept
broker	I-General_Concept
(	O
also	O
known	O
as	O
an	O
integration	O
broker	O
or	O
interface	O
engine	O
)	O
is	O
an	O
intermediary	O
computer	O
program	B-Architecture
module	I-Architecture
that	O
translates	O
a	O
message	O
from	O
the	O
formal	O
messaging	O
protocol	O
of	O
the	O
sender	O
to	O
the	O
formal	O
messaging	O
protocol	O
of	O
the	O
receiver	O
.	O
</s>
<s>
Message	B-General_Concept
brokers	I-General_Concept
are	O
elements	O
in	O
telecommunication	O
or	O
computer	O
networks	O
where	O
software	O
applications	O
communicate	O
by	O
exchanging	O
formally-defined	O
messages	O
.	O
</s>
<s>
Message	B-General_Concept
brokers	I-General_Concept
are	O
a	O
building	O
block	O
of	O
message-oriented	B-Application
middleware	I-Application
(	O
MOM	O
)	O
but	O
are	O
typically	O
not	O
a	O
replacement	O
for	O
traditional	O
middleware	O
like	O
MOM	O
and	O
remote	B-Operating_System
procedure	I-Operating_System
call	I-Operating_System
(	O
RPC	O
)	O
.	O
</s>
<s>
A	O
message	B-General_Concept
broker	I-General_Concept
is	O
an	O
architectural	O
pattern	O
for	O
message	O
validation	O
,	O
transformation	O
,	O
and	O
routing	O
.	O
</s>
<s>
It	O
mediates	O
communication	O
among	O
applications	O
,	O
minimizing	O
the	O
mutual	O
awareness	O
that	O
applications	O
should	O
have	O
of	O
each	O
other	O
in	O
order	O
to	O
be	O
able	O
to	O
exchange	O
messages	O
,	O
effectively	O
implementing	O
decoupling	B-Application
.	O
</s>
<s>
Message	B-General_Concept
brokers	I-General_Concept
can	O
decouple	O
end-points	O
,	O
meet	O
specific	O
non-functional	O
requirements	O
,	O
and	O
facilitate	O
reuse	O
of	O
intermediary	O
functions	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
message	B-General_Concept
broker	I-General_Concept
may	O
be	O
used	O
to	O
manage	O
a	O
workload	O
queue	O
or	O
message	B-Operating_System
queue	I-Operating_System
for	O
multiple	O
receivers	O
,	O
providing	O
reliable	O
storage	O
,	O
guaranteed	O
message	O
delivery	O
and	O
perhaps	O
transaction	O
management	O
.	O
</s>
<s>
Message	B-General_Concept
brokers	I-General_Concept
are	O
generally	O
based	O
on	O
one	O
of	O
two	O
fundamental	O
architectures	O
:	O
hub-and-spoke	O
and	O
message	B-Application
bus	I-Application
.	O
</s>
<s>
In	O
the	O
first	O
,	O
a	O
central	O
server	O
acts	O
as	O
the	O
mechanism	O
that	O
provides	O
integration	O
services	O
,	O
whereas	O
with	O
the	O
latter	O
,	O
the	O
message	B-General_Concept
broker	I-General_Concept
is	O
a	O
communication	O
backbone	O
or	O
distributed	O
service	O
that	O
acts	O
on	O
the	O
bus	B-General_Concept
.	O
</s>
<s>
Redis	B-Operating_System
An	O
open	O
source	O
,	O
in-memory	O
data	O
structure	O
store	O
,	O
used	O
as	O
a	O
database	O
,	O
cache	O
and	O
message	B-General_Concept
broker	I-General_Concept
.	O
</s>
