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The Computer Revolution/Security/Encryption

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More people every day are using the internet and one of the most asked question is "how safe is the internet?" Lots of people use the internet to do their shopping. That involves giving our credit card number, our name, birthday, address and sometimes includes our social insurance number. This is everything one would want to create an internet crime. In order for this to work most websites work with encryption. Encryption is a way of encoding information in such a way that only the person or a computer with a key is able to decode it. It is a science of cryptography which has started its use mostly with government and military purposes. It has been used in history as far ago as the Roman Empire. Encoding works like this: every encryption needs a key that will encode the message, if you write something for your friend who is across the world and he knows that every letter in your message is moved up by 3 alphabet characters than he will be able to encrypt the message. Who ever else looks at the message it would not make any sense to them. There is public key encryption and this example was of symmetric key encryption. Public key encryption is used by a main computer and the computer that it wants to communicate with. It uses both the public key as well as private key. The most popular public key encryption is PGP (pretty good privacy).

A Web-Based Encrypted E-mail is used to avoid the need to get the recipient's public key before sending that person an encrypted e-mail. It's similar to regular web-based e-mail, but encrypted e-mail uses secure web servers to host the webpages that are used to write and read e-mail messages. An example of a we-based encrypted e-mail service is HushMail, which requires both the sender and the recipient to have accounts with them. There are other services that only need the sender to have an account and the receiver is sent an e-mail with instructions on how to view the message on a secure web page.

There are various strengths of encryption available and the stronger the encryption the harder it is to break. Older 40 bit encryption is considered weak. Strong encryption is 'strong 128-bit encryption' and 'military-strength 2,048-bit encryption'. You have to be wary of using some of these because terrorists use encryption methods to communicate and so stronger encryption is monitored by law enforcement.

In the case of a lost or stolen computer, full disk encryption (FDE), is a way to protect data on an entire computer. The operating system, application programs, data, temporary files, and everything stored on the drive can be encrypted using FDE systems. A username and password is all that is needed to access a hard drive that uses FDE.

Ctr encryption


Document Encryption in Microsoft Office

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There is a way to encrypt documents created using Microsoft Office to increase the security of your documents. Although this feature is not new to Microsoft Office, many people may not be aware of the availability of this feature since it is not made obvious on each of the programs. Adding this extra level of security to your documents can have added value and convenience especially when keeping your files on a flash drive or on a public drive at work in which all employees have access to all files. To add simple password protection, you must click the Office button (located at the very top left hand corner and displays the Microsoft Office icon), then click “Prepare” and then click “Encrypt Document”. A window will open up and ask you to enter your chosen password and another window will open up and ask you to confirm your chosen password. An important thing to remember is that if you forget your password, it CANNOT be recovered. For more information on this and other password options, go to the following link: 2007 Microsoft Office Document Encryption