Encryption is an effective tool for minimising the risks of using communications technology whenever there is a need to send sensitive data through a public network or other non secure channels.
Messages transmitted through data communications channels can be subjected to passive and active threats. A passive threat is an intrusion type eavesdropping, whereby an intruder intercepts messages to view the message data. With an active threat, the intruder modifies the intercepted messages.
Basically, encryption encodes data using cryptography techniques in such a way that only the sender and the recipient of the data can read it.
Data is encrypted by the sender using cryptographic algorithms that transform the data appearance but not its meaning. The data that is then transmitted to the recipient does not make sense to an intruder, but the recipient decrypts the data by using similar cryptographic algorithms then transforms the unreadable data back into the original readable data.
There are different types of encryption with different levels of complexity. As with any code, encryption can be broken given sufficient time and resources, although available cryptographic tools that do not need to be kept secret can make it extremely difficult to unscramble encrypted data.
Encryption is supposed to provide data with authentication, integrity, non-repudiation, and secrecy:
- authentication allows the recipient of a message to validate its origin
- integrity allows the recipient to be assured that the data was not modified or otherwise recognize that it was indeed modified during the communication, since modifications cannot be prevented
- non-repudiation can provide the recipient with proof of the data origin by assuring the identity of the sender and/or providing the sender with the assurance that the data was delivered properly
- secrecy or confidentiality prevents disclosure of the data to unauthorized users
Cryptographic algorithms require the data to be mapped, and, at a minimum, require a value called a key to control the mapping process. Given the same text and the same algorithm, different keys produce different mappings, and these keys do need to be kept secret.
Some systems use two different keys to encrypt and decrypt data. The two keys are linked together mathematically. A person's public key is distributed to other users and is used to encrypt messages to that person. The person keeps the private key secret and uses it to decrypt messages sent with the public key.
Data encryption has several uses for electoral purposes. Whenever sensitive data such as personal information or voting data needs to be sent over a public network, it is advisable to encrypt it.
Encryption technology is a rapidly changing field. Therefore, it is advisable to consult an expert in encryption to ensure that the most up-to-date available technology is used.