In the last entry, we learned about encoding. In this part, we will take care and cover the central concepts of an information system, as well as the central structure of the Internet as well as communication channels in the internet and aspect to the security of such communication.

Central concept of an information system

Part of an information system are:

1. Data: These are raw information, that are processed by the information system.

   • By processing these raw information, we get information

   • data can be available in many different forms, such as text, numbers or images

2. Hardware: These are physical components, such as computers, servers or storage medias

3. Software: This describes executables, that process and analyze data through inputs, decisions and more.

4. User: The user inputs data, makes decisions and more, so that the software can process and analyze such data.

5. Network: For getting data from one device to another, the network is used. Networks can be either wireless or with the use of cables.

Central structures of the Internet

The internet consists of following things:

1. End-devices: These are physical devices that can communicate with the Internet, for example smartphones, tables or laptops

2. Network-Infrastructure: This describes the multitude of networks, that are connected with each other.

3. Router: These are the access points. They send data packages between different networks.

   Also, they make communication between end-devices possible.

4. Protocols: These are communication protocols, such as Internet Protocol (IP), that are handling the addressing and the transmission of data.

5. Server: They host the websites, applications and services through the internet.

6. DNS (Domain Name System): They translate domain names into their IP-addresses.

7. Provider (Internet Service Provider [ISP]): They offer the access to the Internet and provide necessary structures and services.

Communication channels

We differentiate between two communication forms:

1. Asynchronous forms: These are time-varying communication channels. The communication does not happen at the same time. These are for example emails and weblogs.

2. Synchronous forms: These are communication channels, that happen at the same time. These are for example video chats, but also normal chats count as synchronous communication forms.

Aspects to the security of the communication on the Internet

For making sure, that the communication is secure, we use several aspects:

1. The encryption: The data are encrypted during the communication through procedures like SSL.

2. Authentication: This means the securing, that the user really is the user and that information aren't sent to a random device. This can happen for example through usernames and passwords.

3. Integrity: This secures, that the data is not manipulated or faulty during their transmission. This can happen trough hash-functions.

4. Firewalls: These monitor the network-connections and filter out unwanted data connections.

5. Protocol: This means for example the HTTPS-Protocol. They are supposed to prevent attacks like the Man-In-The-Middle-Attacks.

6. Updates: Also important are security-updates and patches, that are closing vulnerabilities, that could be used to endanger the security of communication through the internet.

Now you have a basic understanding of information systems and the internet. We will cover the understanding of databases next, so stay tuned.