You will want to consider a number of encryption types.
File encryption: File encryption means that individual files are encrypted with a password. This type is appropriate when sending a confidential file over an open line, for example Internet Mail. This method works for small amounts of data, but becomes too unwieldy as the volume of data increases. Directory encryption: This encryption type is appropriate in networks to prevent access from users which have rights to read other users' data. It may also be useful for protecting data on diskettes or a local hard disk in the absence of other methods of security.
Master Boot encryption: This encryption type allows you to hide the partition data of the computer. This ensures that no-one can gain access to the hard disk after booting from diskette. The data itself, however, is unencrypted, and can be read using a low-level tool for reading sector by sector. Many system viruses can damage Master Boot encryption, making it necessary to partition and reformat the disk from scratch, depending on how the encryption is performed.
Full hard disk encryption: This encryption type encrypts every single sector on the entire disk. Even when a low-level tool is used from a startup diskette, no meaningful data can be read.
COM port encryption: This encryption type is designed to protect communication using a modem however, it has been superseded by hardware solutions built-in to firewalls or modems.
LPT port encryption : A combination of software and hardware will need to be used to encrypt data dent to the printer. Some solutions automatically encrypt print data, with hardware connected to the printer to ensure that what is printed makes sense. The possibility ofmonitoring the printer cable is the reason why some people need this solution.