If the useful life of the Data Encryption Standard (DES) was about 20 years (1977–1999), how long do you predict the useful life of the Advanced Encryption System (AES) will be? Justify your answer

Question

What will be an ideal response?

Answer 1

Part
of
the
reason
for
the
demise
of
DES
has
been
the
increase
in
computing
power,
so
in
1999
it
became
feasible
to
perform
an
exhaustive
key
search
of
a
56-­?bit
space.
The
AES
key
length
of
128,
192,
or
especially
256
bits
should
be
immune
to
exhaustive
search
for
many
more
years,
even
if
Moore's
law
continues
to
hold
(and
computing
power
doubles
every
1.5
years).
The
result
of
exercise
28
gives
a
figure
for
encryption
(and
brute-­?force
decryption);
the
end
of
AES
occurs
when
2128
times
that
figure
divided
by
2n
(where
n
is
the
number
of
1.5-­?year
periods)
is
short,
for
example,
1
month.