Introduction

Access Security

The first safety precaution that a user can take is to secure access to their computer.  If you want to keep people from using applications of your personal computer or have information that you wish to keep secure, then security measures should be taken.  This is quite simple to do if you are serious about controlling the access to your computer.  Install software security packages that use passwords to ensure only authorized users have access. In most cases, a password is your first line of defense against prying eyes. That means you have to be smart about choosing one that will be easy to remember, but hard to guess. Some password guidelines to follow when choosing a password are:

·          Length of passwords should be eight characters

·          Avoid words found in the dictionary and include at least one numeric character (six character passwords may suffice for non- dictionary words)

·          Choose passwords not easily guessed by someone acquainted with the user (for example, passwords should not be maiden names, or names of children, spouses, or pets)

·          Do not write passwords down anywhere

·          Change passwords periodically

·          Do not include passwords in any electronic mail message

Access to this software is readily available and users are encouraged to use password control capabilities that are part of many data base management packages.  Another precautionary measure to take is to periodically review overall access controls to determine weakness of the system.  An important note is taking special care when choosing passwords for applications with access to extraordinary system capabilities (for example, the ability to read personal or restricted data or the ability to modify system software).  For most regular personal computer users this is suffice.  If a computer contains confidential or sensitive information more drastic measures should be taken, such as encryption.
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Encryption

A good data access control system should have the power to deprive information from unauthorized users even if they manage to break some site or system access barriers (if there are any). This demand dictates the use of data encryption.  Encryption is particularly interesting for the personal computer users because PCs, due to their hardware and system software design, are vulnerable to unauthorized access.

Here is some background of what encryption entails and how it works to some extent. 

Modern encryption is achieved with algorithms that use a "key" to encrypt and decrypt messages by turning text or other data into digital gibberish and then by restoring it to its original form.  The reason encryption is effective is that the longer the "key," the more computing required to crack the code. To decipher an encrypted message by brute force, one would need to try every possible key. Computer keys are made of bits of information, binary units of information that can have the value of zero or one. So an eight-bit key has 256 (2 to the eighth power) possible values. A 56-bit key creates 72 quadrillion possible combinations.  New technology has now made it possible for 128-bit keys, which is currently thought of as uncrackable without a great amount of effort.  As you can see, encryption can provide personal computer users with the level of data secrecy that can satisfy even the most demanding requests. However, the site or system access control measures must not be neglected. Ideally, encryption should be a security layer after the site or system access controls mentioned earlier.  Encryption is not the only option for security.  Another popular security application is that of firewalls.
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Firewalls

A firewall is a system or group of systems that enforces an access control policy between two networks. The actual means by which this is accomplished varies widely, but in principle, the firewall can be thought of as a pair of mechanisms: one that exists to block traffic, and the other, which exists to permit traffic. Probably the most important thing to recognize about a firewall is that it implements an access control policy. If you don't have a good idea what kind of access you want to permit or deny, simply have someone or some product configure a firewall based on what they or it think it should do, therefore making policy for you.

A good question to ask before obtaining a firewall might be what a firewall protects against? Some firewalls permit only Email traffic through them, thereby protecting the computer against any attacks other than attacks against the Email service. Other firewalls provide less strict protections, and block services that are known to be problems.  Generally, firewalls are configured to protect against unauthenticated interactive logins from the "outside" world. This, more than anything, helps prevent vandals from logging into your PC. More elaborate firewalls block traffic from the outside to the inside, but permit users on the inside to communicate freely with the outside.

For most users the extent of computer security is quite small.  Most users may not even feel the need to encrypt their files or use firewalls to prevent outside interference.  If you are looking into encryption or firewalls, there are organizations to help you find the right security measures for you.  As for users that there is no need for that technology, a more important matter is the concern of viruses and worms.  Viruses and worms are the concerns of the majority of personal computer users and you should be aware of what you can do in the their prevention.
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Viruses and Worms

A computer virus is a piece of software that has been written to enter your computer system and "infect" your files. Some viruses are benign and won't harm your system, while others are destructive and can damage or destroy your data. A worm is a small computer program that can replicate itself, and like a worm, wiggle its way through a computer network until unleashed onto the Internet. The two main ways viruses and worms can enter your system are through files added to your system from floppy disks (or other removable media like Zip disks) and from downloading from the Internet or private bulletin boards.  You can also get a viruses and worms through an e-mail attachment, but not from a plain text email message alone.  For more information on viruses you can go to these two sites Timberwolf Software or 4virus.  Here are six steps to follow in order to protect yourself from viruses and worms.

1.       Get anti-virus software and update it frequently because new viruses appear all the time.

2.       In general, you should be very wary about inserting floppy disks from unknown sources into your disk drive, especially if the disks have been shared by several other people.  Sometimes you have no choice. In those cases, the second thing you should do (after putting the disk in your drive) is to scan the disk with anti-virus software.

3.       Download with care. To be safe, download all files into a special folder on your hard drive. Then be sure to scan those files before you open them.

4.       Scan attachments before reading them.  While it is impossible to get a virus simply by reading an email message, it is very possible to get one through an attachment.

5.       Save shared files in RTF or ASCII format.  If you want to share data on a network server, and you want your computing experience to remain perfectly virus-free, save all files in RTF or ASCII format.

6.       Back up everything.  Back up your work files and system configuration files regularly. Store these backups in a safe place, separate from your hard drive.

By following these six easy steps you should be able to keep your PC from being infected by a virus or worm.  The important thing to note is that updating your anti-virus software is the most important step due to the appearance of new viruses and worms weekly.  A variety of packages and updates can be gained through the Internet.  Two great sites to get anti-virus packages are Norton.com and McAfee.com.
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Protection From Hackers

Conclusion

This project was produced for PSY 380, Social Psychology of Cyberspace, Spring 2000, at Miami University.  All graphics in these pages are used with permission or under fair use guidelines, are in the public domain, or were created by the authors. Last revised:  
Comments and Questions to R. Sherman.