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What is data privacy?
Let's say that ABC, Inc. creates a very important confidential
memo intended for its largest client, Widget Enterprises. Because
of this memo’s importance, ABC decides to send a backup
copy of this memo to one of its servers in another city. However,
ABC fails to properly secure the information contained within
the memo before transmitting the backup copy across the Internet
to its remote server. A hacker intercepts ABC’s confidential
memo, and since the information within the memo has not been
secured, he is able to read the memo and then distribute the
document to whomever he chooses.
A critical aspect of backing
up data is ensuring the privacy of the data being protected.
Privacy means that only the individuals
who are intended to have access to the information are able
to access it. If ABC, Inc. had encrypted the data in the memo
using
a method such as Triple DES encryption prior to Internet transmission,
the hacker would have been unable to gain access to ABC’s
confidential business information.
What is Triple DES Encryption?
For over twenty years, DES has been subject to intense scrutiny,
and there are NO known algorithmic flaws. CST Stockade uses
Triple DES (3DES) utilizing a 168 bit key. How much more
secure is Triple DES? Let’s put it this way: Triple
DES is 256 times stronger than DES. So, that means if a computer
could be built which was able to crack a DES key by brute
force in 1 second, it would that same computer take two billion
years to crack a Triple DES key in the same way.
How does CST Stockade utilize Triple DES encryption?
Upon installation of the CST Stockade backup client, the
customer creates a password phrase which will be used to
Triple DES
encrypt the backups. This password is itself encrypted on
the customer’s
machine, and is available only to his backup client program.
The password does not leave the customer’s machine,
and is known only to the person who types it in. CST Stockade
software
automatically encrypts the customer’s initial backup,
as well as each subsequent backup, using the Triple DES encryption
method with the customer’s password. CST Stockade
assembles the customer’s backups into secure archive
files (.ESA files). When the CST Stockade customer has completed
his or
her initial backup, the CST Stockade software will automatically
scan the client’s computer for new and changed information
on a nightly basis. The scan recognizes new files as well
as modified portions of files that have changed since the
previous
backup.
CST Stockade then assembles only the block level
changes into a single ESA file which is then compressed to
one or
two percent
of its original size. The ESA file is stamped with the time
and date and then encrypted for security. This technology
enables CST Stockade to reduce backup sizes and speed the
transmission
of the customer’s backup via the Internet.
Before the
customer’s backup set is transmitted over the
Internet, CST Stockade creates another level of security
for our clients. The customer’s ESA file undergoes
another layer of Triple DES encryption. Therefore during
Internet transmission,
CST Stockade customer backups are encrypted with two layers
of Triple DES encryption. After the ESA file has been created
and doubly encrypted, the CST Stockade software contacts
the CST Stockade data centers and the customer’s backup
is transmitted to the CST Stockade servers. When the customer’s
backup set has been received at our data centers the outer
layer of Triple DES encryption is removed, but the first
layer of Triple
DES encryption remains intact during the entire time the
customer’s
ESA files reside on our servers.
CST Stockade customers
can quickly restore their own files with a few clicks of
the mouse. CST Stockade technical support
personnel
are available on a 24/7/365 basis for needed assistance.
When customer’s retrieve information their ESA file(s)
will arrive on their machines in an encrypted format. The
customer
must type the password to restore the data.
Additional technical
information about Triple DES
The DES algorithm (DES stands for Data Encryption Standard)
is based on work by IBM and was published as a federal standard
in 1977. It was designed to provide a means to protect the
confidentiality
of the government’s sensitive unclassified computer
information. The original DES algorithm has been reviewed
and reaffirmed on
several occasions. The DES standard requires 16 rounds of
operations to mix the data and key together to produce the
ciphertext, and
the same number of rounds to change the ciphertext back to
plaintext. There have been statements that “DES running
in only 6 or 8 rounds can be easily broken.” The standard
calls for 16 rounds, and any implementation with other than
16 rounds is
not DES. There has never been a successful challenge to the
mathematical soundness of the algorithm.
Nonetheless, with
the power and speed of present day computers,
it is possible, by mounting a sophisticated and massive brute
force attack on the key, usually with multiple computers,
it is possible to completely explore the keyspace and discover
the key. This is done by trying every possible key. With
256
keys
(72,057,594,037,927,940) to explore it takes a while, but
can be done. However, Triple DES (or TDEA -Triple Data Encryption
Algorithm) utilizes three rounds of DES using 3 different
keys
to provide a keyspace of 2168 or 374,144,419,156,711,800,000,000,000,000,000,000,000,000,000,000,000
different possible keys. Even using thousands of very fast
computers, exploring the keyspace is impractical. Therefore
the Secretary
of Commerce, through the National Institute of Standards,
has issued the following directive (FIPS46-3):
“
This standard became effective July 1977. It was reaffirmed
in 1983, 1988, 1993, and 1999. It applies to all Federal
agencies,
contractors of Federal agencies, or other organizations that
process information (using a computer or telecommunications
system) on behalf of the Federal Government to accomplish
a Federal function.
Each Federal agency or department may issue internal directives
for the use of this standard by their operating units based
on their data security requirement determinations.
With
this modification of the FIPS 46-2 standard:
- Triple DES
(i.e., TDEA), as specified in ANSI X9.52 will be recognized
as a FIPS approved algorithm.
- Triple DES will be the FIPS
approved symmetric encryption algorithm of choice.
- Single
DES (i.e., DES) will be permitted for legacy systems only.
New procurements to support legacy
systems should,
where feasible, use Triple DES products running
in the single DES
configuration.
- Government organizations with legacy
DES systems are encouraged to transition to Triple DES based
on a prudent
strategy that
matches the strength of the protective measures
against the associated risk.”
The implementation
used by CST Stockade is through the Bokler Software
Corporation DLLs, which have
been validated
by the
National Institute of Standards as conforming
to the Triple Data Encryption
Algorithm (TDEA, a.k.a. "Triple DES"),
as specified in Federal Information Processing
Standard
Publication 46-3,
Data Encryption Standard (DES), Certificate Number
12. CST Stockade use all three keys, providing
a 168 bit encryption level.
© 2005, CST Stockade
Microsoft, MS Word, MS Excel, MS Outlook,
Windows 95, 98, NT, 2000, & XP are registered trademarks
of Microsoft Corporation.
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