Glossary

Asymmetric cryptography

Also known as public key cryptography. A method that sidesteps the key distribution problem, as each user creates their own keys: • the private key, which they keep safe and never distribute • the public key, which can be sent to anyone with whom they want to exchange encrypted information.

Bitcoin

A digital currency that is mainly used online. However, it can be bought or sold with real money at bitcoin exchanges.

Botnet

A network created by malware that allows an attacker to control a group of computers and use them to gather personal information or launch attacks against others, such as sending spam emails or flooding a website with so many requests for content that the server cannot cope.

Cipher

A mathematical algorithm that turns plaintext into ciphertext and reverts ciphertext to plaintext.

Ciphertext

Information that is encrypted such that it cannot be directly read by humans or a machine.

Countermeasure

An action you take to protect your information against threats and vulnerabilities.

Decryption

The process of reverting ciphertext to plaintext.

Distributed denial of service (DDoS)

A type of attack that floods computer servers with a massive amount of traffic coming from many different computers or computing devices. A DDoS attack can render a server unable to provide services to their legitimate users.

Domain Name System

The system that translates alphabetic internet domain and host names, such as the website addresses you enter into web browsers, into numeric IP addresses. Without this translation, the website names would not be converted to computer-readable numeric IP addresses and hence the web browser would not be able to connect to the website you want to go to.

Encryption

The process of converting plaintext to ciphertext.

EternalBlue

A hacking tool that exploits a defect in Microsoft’s implementation of the Server Message Block protocol, discovered in March 2017.

Firewall

In a computer network, a firewall is a barrier that blocks dangerous communications from spreading across a network, either from the outside world into a local network, or from one part of a local network to another.

Intrusion detection system

An intrusion detection system is used to monitor data passing over a network or a computer in order to detect intrusion.

Key

In the context of cryptography, a secret that is used to encrypt or decrypt messages.

Mirai

Malware that attacks and takes over unsecured consumer devices and uses them to launch distributed denial-of-service attacks on websites.

Plaintext

Information that can be directly read by humans or a machine.

Programmable logic controllers

Very commonly used programmable controllers, which are often used to control industrial motors.

Ransomware

Malware that demands payment in order to refrain from doing some harmful action or to undo the effects of the harmful action.

Relational database

A very commonly used database type. This type of database organises data in tables and links the tables using indexes.

Script

A small piece of computer program that aims to automate a process.

Secure Shell

A network protocol for providing a remote terminal. SSH is more secure than Telnet because it uses encryption to protect the transmission of the data.

Server Message Block

A protocol that allows applications on a computer to access files and services on other computers in a network.

Structured Query Language injection

A hacking technique for gaining unauthorised access to databases through ill-designed web pages.

Stuxnet

Malware specifically designed to target programmable logic controllers. It was believed that the malware was designed by the US and Israeli security agencies to sabotage Iran’s uranium enrichment plant, in an effort to stop or delay its nuclear programme.

Spyware

Malware that records the activities of the user, such as the passwords they type into the computer, and transmits this information to the person who wrote the malware.

Symmetric cryptography

A cryptography method in which both the encryption and decryption processes take place based on a common key. As a result, it is important to keep the key secret.

Teletype Network

A network protocol for providing a remote terminal to control a computer system.

Threat

Some danger that can exploit a vulnerability.

Trojan

A Trojan is malware disguised as something useful and can be self-replicating.

Virus

A virus inserts a copy of itself into applications or crucial parts of the operating system in order to infect other computing devices or storage media that interact with the infected computer.

Vulnerability

A point at which there is potential for a security breach.

WannaCry

Fast-spreading malware that surfaced in May 2017. When it infects a computer, it ‘locks’ the data files (rendering them unusable) and demands a ransom.

Worm

A worm exploits the vulnerability of computing devices in a network and replicates itself by finding and infecting other vulnerable computing devices.