A formula used to turn ordinary data, or "plaintext," into a secret code known as "ciphertext." Each algorithm uses a string of bits known as a "key" to perform the calculations. The larger the key (the more bits), the greater the number of potential patterns can be created, thus making it harder to break the code and descramble the contents.
Most encryption algorithms use the block cipher method, which codes fixed blocks of input that are typically from 64 to 128 bits in length. Some use the stream method, which works with the continuous stream of input.
The dialog box below from the ScramDisk encryption program shows the various algorithms offered to encrypt data on your hard disk. The free, open source, legacy version of ScramDisk is available at www.samsimpson.com. The accompanying descriptions and performance comparisons from the ScramDisk documentation manual are provided because they provide a brief and clear summary of current-day secret key encryption algorithms.
The following is reproduced with permission, courtesy of Sam Simpson and Aman. See mode of operation, cryptography, security protocol, stream cipher, block cipher and algorithm.
ScramDisk Encryption
ScramDisk encrypts data on the hard disk, and this dialog box allows for the selection of the encryption algorithm. "Mouse entropy" is the amount of randomness introduced into the creation of the key. The more the mouse is moved around in a random pattern, the more randomness.
3DES
This is far better than DES; it uses three applications of the DES cipher in EDE (Encipher-Decipher-Encipher) mode with totally independent keys. Outer-CBC is used. This algorithm is thought to be very secure (major banks use it to protect valuable transactions), but it is also very, very slow.
Blowfish
Blowfish is a high security encryption alogorithm designed by Bruce Schneier, the author of Applied Cryptography and owner of the company Counterpane. It is very fast, is considered secure and is resistant to linear and differential analysis. This is my personal cipher of choice.
DES
Data Encryption Standard was designed in the early 1970s by IBM with input from NSA. It is OK, but a single key can be broken in three days by the Electronic Frontier Foundation, a poorly funded organization. This algorithm was provided for completeness.
IDEA
International Data Encryption Algorithm was produced by Xuejia Lai and James Massey. It is fairly fast, is considered secure, and it is also resistant to both linear and differential analysis. To use this for anything other than personal use, a royalty must be paid to Ascom-Systec Ltd.
Misty1
Misty1 was designed by M. Matsui of Mitsubishi. It is a reasonably fast cipher that is resistant to both linear and differential analysis. It is fairly new though, so use it with caution.
Square
Square is a very fast and reasonably secure block cipher produced by John Daemen and Vincent Rijmen. It hasn't been subject to as much peer review as Blowfish, 3DES, IDEA, etc., so it may be susceptible to attacks.
Summer
This is a proprietary stream cipher constructed by the author and is designed for speed alone. It is supplied for backward compatibility with Version 1 of ScramDisk and is not recommended for use on newly created disks. Instead, use TEA or Blowfish, which are both reasonably fast.
TEA
Tiny Encryption Algorithm is a very fast and moderately secure cipher produced by David Wheeler and Roger Needham of Cambridge Computer Laboratory. There is a known weakness in the key schedule, so it is not recommended if utmost security is required. TEA is provided in 16 and 32 round versions. The more rounds (iterations), the more secure, but slower.
Most encryption algorithms use the block cipher method, which codes fixed blocks of input that are typically from 64 to 128 bits in length. Some use the stream method, which works with the continuous stream of input.
The dialog box below from the ScramDisk encryption program shows the various algorithms offered to encrypt data on your hard disk. The free, open source, legacy version of ScramDisk is available at www.samsimpson.com. The accompanying descriptions and performance comparisons from the ScramDisk documentation manual are provided because they provide a brief and clear summary of current-day secret key encryption algorithms.
The following is reproduced with permission, courtesy of Sam Simpson and Aman. See mode of operation, cryptography, security protocol, stream cipher, block cipher and algorithm.
ScramDisk Encryption
ScramDisk encrypts data on the hard disk, and this dialog box allows for the selection of the encryption algorithm. "Mouse entropy" is the amount of randomness introduced into the creation of the key. The more the mouse is moved around in a random pattern, the more randomness.
3DES
This is far better than DES; it uses three applications of the DES cipher in EDE (Encipher-Decipher-Encipher) mode with totally independent keys. Outer-CBC is used. This algorithm is thought to be very secure (major banks use it to protect valuable transactions), but it is also very, very slow.
Blowfish
Blowfish is a high security encryption alogorithm designed by Bruce Schneier, the author of Applied Cryptography and owner of the company Counterpane. It is very fast, is considered secure and is resistant to linear and differential analysis. This is my personal cipher of choice.
DES
Data Encryption Standard was designed in the early 1970s by IBM with input from NSA. It is OK, but a single key can be broken in three days by the Electronic Frontier Foundation, a poorly funded organization. This algorithm was provided for completeness.
IDEA
International Data Encryption Algorithm was produced by Xuejia Lai and James Massey. It is fairly fast, is considered secure, and it is also resistant to both linear and differential analysis. To use this for anything other than personal use, a royalty must be paid to Ascom-Systec Ltd.
Misty1
Misty1 was designed by M. Matsui of Mitsubishi. It is a reasonably fast cipher that is resistant to both linear and differential analysis. It is fairly new though, so use it with caution.
Square
Square is a very fast and reasonably secure block cipher produced by John Daemen and Vincent Rijmen. It hasn't been subject to as much peer review as Blowfish, 3DES, IDEA, etc., so it may be susceptible to attacks.
Summer
This is a proprietary stream cipher constructed by the author and is designed for speed alone. It is supplied for backward compatibility with Version 1 of ScramDisk and is not recommended for use on newly created disks. Instead, use TEA or Blowfish, which are both reasonably fast.
TEA
Tiny Encryption Algorithm is a very fast and moderately secure cipher produced by David Wheeler and Roger Needham of Cambridge Computer Laboratory. There is a known weakness in the key schedule, so it is not recommended if utmost security is required. TEA is provided in 16 and 32 round versions. The more rounds (iterations), the more secure, but slower.
Summary
Block Key
Size Size Speed**
Type Author Bits Bits (m:s)
3DES Diffie & Hellman 64 168 4:05
Blowfish Schneier 64 256 0:55
DES IBM & NSA 64 56 1:42
IDEA Lai & Massey 64 128 1:07
Misty1 Matsui 64 128 2:50
Square Daemon & Rijmen 128 128 0:39
Summer Aman (stream) 128 0:46
TEA 16 Wheeler & Needham 64 128 0:46
TEA 32 Wheeler & Needham 64 128 1:03
**Speed is time to copy a 50MB file from a normal
disk to a ScramDisk on a 166 Mhz Pentium.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2008 The Computer Language Company Inc. All rights reserved. |
Additional Resources
- SmartLayouts (exe)
- SmartLayouts is easy, Innovative and powerful layout manager for Windows forms on .Net platform to ease the designing and development of GUI. It helps in arranging various winforms GUI elements and controls the behaviour of various elements when form is resized or repositioned. It uses unique methodology and algorithm for...
- Software downloads 2008-08-29
- FBI warns 'electronic Pearl Harbor' possible
- FBI warns 'electronic Pearl Harbor' possibleWake Up!Just when are the public and the goverment ever going to realize that there is ABSOLUTELY ZERO SECURITY when it comes to computers? It makes no sense for banks and any goverment agency to have their networks connected to the internet. How many more...
- Discussion threads 2008-08-28
- Windows 7 pricing thoughts - Is Windows too expensive?
- Windows 7 pricing thoughts - Is Windows too expensive?It is an apt comparison>Your Ubunutu/Vista comparison doesn't pass the common sense test. Think about what you can get with Ubuntu-- Compiz Fusion for eye candy, drive encryption, MythTV DVR app, OpenOffice.org, ect. You have to get Ultimate Windows to get all...
- Discussion threads 2008-08-28
- Super Flexible File Synchronizer (dmg)
- Back up your data and synchronize Macs, PCs, servers, notebooks, and online storage space. You can set up as many different jobs as you need and run them manually or using the scheduler. Virtually any kind of storage can be used for the synchronization tasks. The software comes with support...
- Software downloads 2008-08-28
- News to know: IE 8; Code name of the day; Facebook security; Office 2.0
- Here are today's notable headlines. You can get News To Know via email alert and RSS daily: Mary Jo Foley: A Microsoft Codename a day: Rouge Dancho Danchev: Hundreds of Dutch web sites hacked by Islamic hackers Twitter's "me too" anti-spam...
- Blog posts 2008-08-26
- A-PDF Password Security (exe)
- A-PDF Password Security is a desktop utility program that lets you change password security of existing Acrobat PDF files. That means you can protect PDF files with 128 bit encryption or remove the password protection. It can handle either single or batch documents with a wizard. Another convenience feature is...
- Software downloads 2008-08-26
- VGSC (zip)
- For political & economic reasons, ISP may block VoIP in your country. To protect your VoIP business & profit, SpeedVoIP Communication Technology Co. is providing Security VoIP software solution, VGSC 2008, which installed on client sides PC, and support your X-lite, Linksys PAP2 without any VoIP blocking. Key Features: Maximum...
- Software downloads 2008-08-26
- Joe Biden loves RIAA, DRM; hates encryption, George Bush
- Joe Biden loves RIAA, DRM; hates encryption, George BushAre You Ready????To have your privacy taken away? For some joker to place more power with the RIAA and MPAA than your own persons.Anyone to push corporate initiatives to be funded by the tax payers should not be in office. ...
- Discussion threads 2008-08-25
- Joe Biden loves RIAA, DRM; hates encryption, George Bush
- Does Joe Biden have more in common with Metallica's Lars Ulrich than Facebook's Mark Zuckerberg? CNET colleague Declan McCullagh has a superb analysis of Dem. vice presidential candidate Joe Biden, who has an interesting (read: depressing) voting history when it comes to tech issues. ...
- Blog posts 2008-08-25
- Mandatory email
- Mandatory emailWe need better emailFrankly, email is currently broken - spam and scams and phishing make it a mess to wade through, even with the best spam blocking stuff.Problem is, we decided to use "adaptive filtering" statistical junk rather than solid encryption and digital signatures. What do the spammers do?...
- Discussion threads 2008-08-25
- Worker suspended over loss of data on all English prisoners
- Worker suspended over loss of data on all English prisonersCriminals protected?Names, birthdays, and criminal histories of criminals in England are not public information??RE: Worker suspended over loss of data on all English prisonersGood, just what we need: A society where everyone is required to 'think again' based on a sense...
- Discussion threads 2008-08-22
- TCG Vault Quik Client (exe)
- Backup your data now. The TCG America Vault Quik client provides reliable online backup for your data. Small and medium-sized businesses SMBs are rapidly turning to online backup to replace aging, manual, unreliable tape backup. Smaller companies in particular can't afford the complexity of tape or its potential for failure:...
- Software downloads 2008-08-22
- Open source and the 'fear factor' mentality
- Guest editorial by Emma McGrattan In the current economic climate, businesses of every size are looking to reduce their spending wherever possible. Open source software, which has no upfront licensing fees, is one way of achieving significant savings. However, in order to protect their...
- Blog posts 2008-08-20
- New algorithm speeds up networks
- New algorithm speeds up networksThe old days !This remember me the old days when I used Kermit, then X-modem, then Y-modem and finally Z-modem protocols on my simple file transfering on CBBS/BBSes back in 1985.I was using a MSX computer (8-bit) and 1200/75 and 300/300 manual modem. I even...
- Discussion threads 2008-08-20
- SpamZa - opt in spamming service fighting to remain online
- A recently launched unethical spam list building service called SpamZa, is fighting to remain online after providing highly successful (87 spam emails in 8 minutes) into fulfilling its objective, namely, to sign up any email submitted to hundreds of newsletters anonymously. What is SpamZa anyway? SpamZa is...
- Blog posts 2008-08-20
- News to know: IDF; Windows 7 wishes; IE 8; Salesforce.com
- Here are today's notable headlines. You can get News To Know via email alert and RSS daily: Larry Dignan: Salesforce acquires InStranet; Will take it SaaS and better target call centers Ed Bott: My Windows 7 wish list ...
- Blog posts 2008-08-20
- New algorithm speeds up networks
- Routing scalability has always been a problem in networking research. Now, computer scientists at UC San Diego UCSD have developed a new algorithm to improve the routing efficiency of networks. 'Called XL, for approximate link state, the algorithm increases network routing efficiency by suppressing updates from parts of the system...
- Blog posts 2008-08-19
- Is the enterprise ready for cloud computing?
- Is the enterprise ready for cloud computing?My boss likes to look at IT as a cost...center. I asked him the other day to turn off all computers then try to do business. He said he couldn't. Well then it looks like your IT is responsible for 100% of your revenue....
- Discussion threads 2008-08-19
- SanDisk Cruzer Titanium Plus (4GB)
- The 4GB SanDisk Cruzer Titanium ($50) is a new kind of flash drive that offers an automated online backup each time it's attached to a computer with an Internet connection. This model looks almost exactly the same as the original Sandisk Cruzer Titanium, but this one lets you perform automatic...
- Product reviews 2008-08-18
- Searching by color to nibble away at Google.
- Searching by color to nibble away at Google.Must be a slow news day...The reality is, anyone who wants to create such a tool USING Google's index can do so using Google Custom Search. In fact, many are.The fact that someone COULD make a custom search engine using their own...
- Discussion threads 2008-08-18
Neighboring Terms
Premier Vendor Content Whitepapers, webcasts & resources from our Power Center Sponsors
- Marc Canter: The master of multimedia speaks
-
In this Super Techies interview, larger-than-life techie Marc Canter talks with ZDNet's Editor in Chief Dan Farber about his career as a multimedia pioneer.
- Watch the video >>
- Demo: Virtualization with the Intel® Xeon® Processor
-
In this Flash demo, you'll learn about virtualization performance and features ideal for consolidation, load balancing, and disaster recovery with leading enterprise reliability.
- Watch how the Intel Xeon processor can increase performance and reliability of your servers >>
-
-
Tasty Baking’s new LEED factory
0:57
Tasty Baking CIO: Brendan O’Malley
-
Balancing act: innovation vs. reliability
1:28
Facebook VP of technical operations: Jonathan Heiliger
-
Securing data at E-Loan
1:47
E-Loan CIO: Jay Shah
-
When crops are scarce
1:47
Del Monte Foods CIO: Marc Brown
- View all CIO Vision Series Videos »
