Cyberspace is defined by the National Security Presidential Directive 54/Homeland Security Presidential Directive 23 as
“The interdependent network of information technology infrastructures, and includes the Internet, telecommunications networks, computer systems, and embedded processors and controllers in critical industries.”
In other words, cyberspace refers to the virtual environment in which people communicate and interact with others. Cyberspace consists of four different layers: (1) physical layer, (2) logic layer, (3) information layer, and (4) personal layer.
The physical layer consists of physical devices, such as PCs, networks, wires, grids, and routers. These physical devices are located within jurisdictions, which is important for law enforcement when they search for physical devices used to run criminal enterprises and other cybercrimes.
The logic layer is where the platform nature of the Internet is defined and created. Stated differently, cyberspace depends on the design of the Internet. It is built out of components that provide services for users, such as social media, content, shopping, etc.
The information layer includes the creation and distribution of information and interaction between users. Users can create information by building a website, linking to other websites, and posting information on social media websites such as Twitter, Facebook, or Yelp. Users can also access information, including music, books, videos, and pictures.
The top layer consists of people—people who create websites, tweet, blog, and buy goods online.
Attacks on cyberspace can occur at each of the four levels. Communication and interaction can be identified (known) or anonymous. The anonymity of cyberspace creates opportunities for cybercrime that would otherwise not exist and which are different and unique compared to other forms of crime. For instance, hackers would not be able to break into a computer and steal information without cyberspace. The term cyberspace is used because other terms used by the government, such as cybercrime, cyberattack, cyber threat, or cybersecurity, are derived from the term cyberspace.
As you can tell from the definition above, the Internet is a part of cyberspace:
“The Internet is a global system of interconnected computer networks that are set up to exchange various types of data. This ‘network of networks’ connects millions of computers, including those in academic, business, and government networks, transcending geographic and national boundaries.”
Without this global data communication system, people would not be able to interact and exchange information. The term Internet is often used interchangeably with the term web or World Wide Web. The Internet and the web are distinctly different, however.
“Whereas the Internet refers to hardware and software infrastructure that connects computers around the globe, the World Wide Web refers to a service that can be accessed via the Internet. This service consists of interconnected documents and a variety of resources.”
The documents and resources are connected and accessible via hyperlinks and uniform resource locators (URLs). Several web browsers (i.e., Safari, Firefox, and Explorer) allow users to access the information available on the web.
A hyperlink is a reference or navigation element in a hypertext document that offers direct access to another section of the same document or to another hypertext document that is on or part of a (different) domain.
For instance, the hyperlink https://www.fbi.gov/about-us/investigate/cyber takes you to the FBI’s cybercrime website. A hyperlink could also be embedded in words, such as FBI cybercrime website, which is called hypertext. Users can simply click on the word(s) or the link and are directed to the FBI cybercrime website. These hyperlinks provide easy access to information relevant to the content the reader is interested in.
Hyperlinks are unidirectional—that is, a user can link from their content to another website’s content without asking for approval from the owner of the destination page or any action by the owner of the destination page. This unidirectional system allows anybody who has a website to link to other users’ websites.
A hyperlink is one way to get to more content, but users also have other options. For instance, if you are searching for information on the web, you may often use URLs, which provide a reference to a resource on the Internet.
URLs have two main components: the protocol identifier and the resource name. For example, for the website https://www.fbi.gov, the protocol identifier is “https” and the resource name is “fbi.gov.” In this sense, the URL is comparable to the address you would put on a letter to tell the postal service to whom to deliver your letter.