Of
the hundreds of encryption algorithms
available today, Blowfish stands out
as the industry leader and has been
selected by Backup Proshop as its encryption
algorithm.
Blowfish is a symmetric encryption
algorithm designed in 1993 by Bruce
Schneider as an alternative to existing
encryption algorithms such as DES.
Unlike DES, however, the Blowfish
algorithm has a variable key length,
which can be extended from 32 bits
to 448 bits, making this a more secure
alternative. Blowfish is a 64bit
cipher (i.e. a cryptographic key and
algorithm are applied to a block of
data rather than single bits).
Blowfish is a fast, free alternative
to existing algorithms and has been
analyzed considerably through years
of peer review.
Length = Strength
Finding the plain text of an encrypted
message without knowing the key is
called "cracking" an algorithm.
This bruteforce attack consists of
trying all possible values of keys
until the right one is found.
It is easy to demonstrate that in
the case of bruteforce attack, the
security increases together with the
length of the key. If the key is 8
bits long, there are 2(to the power
of 8), or 256 possible combinations.
With a key of 40 bits this is increased
to 2(to the power of 40), or one thousand
billion combinations. The protection
then resides on the time needed for
a computer to perform its attack.
Based on these premises as well as
numerous industry trials, it is common
opinion today that
 40bit key algorithms are useless
as they can be "cracked"
within a few hours by an average
personal computer.
 64bit algorithms are safe today
but will become threatened as technology
evolves.
 128bit and over algorithms are
almost unbreakable. In other words,
it would take millions of years
to try every possible combination
of bits in a 128bit key.
Based on calculations it can be said
that a 128bit encryption is not just
three times stronger than a 40bit
encryption—it is 309,485,009,821,345,068,724,781,056
times stronger. Likewise, a 448bit
encryption key is 2.1 x 1096 times
stronger than a 128bit key.
Conclusion
Backup Proshop considered many factors
when choosing Blowfish as its encryption
technology, including peer review,
speed and key strength. It is clear
that Blowfish will set the standard
for years to come, and will continue
to be the preferred encryption algorithm
for corporations worldwide.
