Cyberspace (サイバー空間) is the virtual space connected by the internet and other networks, where people and organizations exchange information and carry out activities.
It refers to a place built on communication lines and computers, as opposed to physical places such as streets and buildings. Shopping, government procedures, business operations, and many other social and economic activities happen there, so damage done in it turns directly into real-world losses.
AnalogyPicture a second town alongside the one linked by roads and stations, this one linked by communication lines, where shops still open, people still gather, and deals still get made.
How to rememberThe word cyberspace spread from the novels of science fiction writer William Gibson.
A cyberattack (サイバー攻撃) is the umbrella term for acts that tamper with systems or information without authorization in order to cause harm, carried out through networks or computers.
The goals vary, such as stealing information, altering content, or making a service unusable, and the methods are just as varied. Individual methods such as malware and unauthorized access all fall under this umbrella term.
AnalogyOf all the theft, vandalism, and business disruption that happen in a town, a single word for the ones that arrive over communication lines.
Exam points
ExamA cyberattack (サイバー攻撃) means an attack carried out by way of networks or computers. Purely physical acts, such as peeking at or carrying off physical items, are not included.
ExamThe cyber kill chain (サイバーキルチェーン) is a model that splits the course of a cyberattack, from initial reconnaissance to achieving its final goal, into several stages.
An information asset (情報資産) is a collective name for information that has value to an organization and must be protected, together with the media and equipment used to record and process it.
Examples of information assets
The information itself (customer data, design drawings, etc.)
Storage media and paper documents
Equipment and software that handle information
Not only the data but also the media and documents that store it and the equipment and software that process it are treated as things to protect. A factor that can lead to harm to information assets is called a threat, so information security can be described as the work of protecting information assets from threats.
AnalogyFor a library, the property worth protecting is not just the books but also the lending records, the keys to the stacks, and the search terminals used to find books.
How to rememberAn asset is something whose value can be turned into money. Once you see that information has a price too, the reason to protect it becomes clear.
Exam points
ExamA threat (脅威) is a factor that can cause damage to information assets (情報資産), and it is a different thing from a weakness in a system that attackers exploit (a vulnerability, 脆弱性).
Leakage (漏えい) is damage in which information that should not be shown flows outside, so that unauthorized people learn its content.
The property that only authorized people can see information is called confidentiality, and leakage is the state in which it has been harmed. It happens when information is copied or when someone sneaks a look at a screen.
AnalogySomeone opens a safe with a duplicate key and photographs the documents inside.
How to rememberThe kanji 漏 depicts water dripping out of a container. Remember it as the contents seeping outside.
Loss (紛失) is damage in which information, or the media or equipment that hold it, go missing, so it cannot be used when needed.
The property that information can be used when needed is called availability, and loss is the state in which it has been harmed. It happens when a laptop or USB memory stick carried around is left behind, or when no one can find where documents were stored.
AnalogyYou drop your wallet, and the money inside is no longer yours to spend.
How to rememberThe kanji 紛 means to get mixed in with other things. Read the word as something that got mixed in and lost from sight.
Exam points
Mix-upLoss (紛失) alone does not necessarily mean the content was seen. If a third party who picks it up looks at the content, however, it also leads to leakage (漏えい).
Corruption (破損) is damage in which information or equipment breaks, so the correctness of its content (integrity) or its usable state can no longer be maintained.
If a file's content breaks and can no longer be read correctly, integrity is harmed, and if equipment or media break and stop working, availability is harmed. Which property is harmed depends on what broke and how.
AnalogyWater spills on a notebook and the ink runs, so what you wrote becomes unreadable or looks like different words.
How to rememberThe word combines 破 (to tear or break) and 損 (to impair). Read it as the form breaking and the value dropping.
Cracking (クラッキング) is the act of breaking into someone else's computer or system without permission and with malicious intent, then snooping on, destroying, or altering information.
Among cyberattacks, it refers to getting inside a system without authorization to do harm, and the person who does it is called a cracker. The way in is often an easily guessed password or an unpatched weakness in software.
AnalogyForcing a lock to get into someone's house, then stealing things or wrecking the rooms.
How to rememberThe English verb crack means to split or break open. A safe burglar is called a safecracker.
Exam points
ExamCracking (クラッキング) is a malicious act of entering someone else's system without permission to peek at or destroy information.
Mix-upHacking (ハッキング) broadly means technical activity that explores or manipulates systems in depth, and it does not necessarily involve malice. The word that specifically means malicious intrusion and destruction is cracking (クラッキング).