<s>
Bilateral	B-Protocol
key	I-Protocol
exchange	I-Protocol
(	O
BKE	O
)	O
was	O
an	O
encryption	O
scheme	O
utilized	O
by	O
the	O
Society	B-Protocol
for	I-Protocol
Worldwide	I-Protocol
Interbank	I-Protocol
Financial	I-Protocol
Telecommunication	I-Protocol
(	O
SWIFT	B-Language
)	O
.	O
</s>
<s>
All	O
key	O
management	O
is	O
now	O
based	O
on	O
the	O
SWIFT	B-Language
PKI	O
that	O
was	O
implemented	O
in	O
SWIFT	B-Language
phase	O
two	O
.	O
</s>
<s>
A	O
bilateral	O
key	O
allowed	O
secure	O
communication	O
across	O
the	O
SWIFT	B-Language
Network	I-Language
.	O
</s>
<s>
The	O
text	O
of	O
a	O
SWIFT	B-Language
message	O
and	O
the	O
authentication	O
key	O
were	O
used	O
to	O
generate	O
a	O
message	B-Algorithm
authentication	I-Algorithm
code	I-Algorithm
or	O
MAC	O
.	O
</s>
<s>
This	O
was	O
normally	O
accomplished	O
by	O
the	O
exchange	O
of	O
various	O
SWIFT	B-Language
messages	O
used	O
specifically	O
for	O
establishing	O
a	O
communicating	O
key	O
pair	O
.	O
</s>
<s>
BKE	O
keys	O
were	O
generated	O
either	O
manually	O
inside	O
the	O
SWIFT	B-Language
software	O
,	O
or	O
automatically	O
with	O
the	O
use	O
of	O
a	O
secure	O
card	O
reader	O
(	O
SCR	O
)	O
.	O
</s>
<s>
Since	O
1994	O
,	O
the	O
keys	O
used	O
in	O
the	O
card	O
reader	O
and	O
the	O
authentication	O
keys	O
themselves	O
were	O
1,024	O
bit	O
RSA	B-Architecture
.	O
</s>
