What is an IP address?

Again and again, you hear about the so-called IP address. But what is an IP address? The IP address is to be compared with the address of a house. With this address, you can find the house and, for example, deliver mail. This scheme is also used on the Internet to send data to the right computer. The network standard used here is the Internet Protocol (IP).

The IP address as the address of the computer

Each computer with Internet access has one or more IP addresses. With such a unique address, the device can be identified with Internet access. Only then also the data arrive on the computer, which is requested over this. When a web page is called, the browser transmits the IP address of the computer. Thus, the server on which the data to be retrieved receives a delivery address. Only through the IP address to the requested data come back to the polling computer.

What form does an IP address have?

Widely known are the IP addresses of the old IPv4 standard. Here, the IP address consists of four numbers ranging from 0 to 255. The four numbers of the IP address are separated by dots, so an IP address looks like this:

192.167.0.2.

Since only a limited number of IP addresses can be represented with this old variant, there is the newer IPv6 standard. This IP address is significantly longer and includes letters as well as numbers. Overall, the IP address consists of eight character blocks, zeros may also be replaced by colons so that the IP address is clearer.

What is my IP address: can be static or dynamic

The IP address can be used to find out the provider that assigns the address and the approximate location of the device. However, an IP address is usually reassigned for each Internet session, so a device does not always have the same IP address. This is because the providers usually have a limited number of addresses and distribute them as needed, as never all users will be online at the same time. However, in addition to this dynamic allocation of IP addresses, there are also static addresses, such as for servers and leased lines. The private customer will usually receive a dynamic IP address.

The IP address in the home network

In your own home, you get from these allocations of providers once very little. Your own devices, be it PC or smartphone, are not directly connected to the Internet, but only with the in-house router, which acts as a so-called “gateway” and over which all requests run – the router is virtually an Internet distributor. Mostly in the home network, dynamic IP addresses are used, which are assigned internally by the router but are not visible to the outside.

How do I find out my IP address?

The address visible on the Internet, that of the router, can often be found most simply by asking the search engine of your own trust kindly: “What is my IP address?”,

The Dynamic DNS or DDNS (in Dynamic English ) is a service that allows you to associate a DNS name always to the same public IP address of a host.

To better understand how the DDNS works in the first part of the guide we will describe how communication takes place on the network and what the DNS is. In the second part of the guide, we will explain instead how it works and what the Dynamic DNS is for.

Difference between internal and external IP addresses

Basically, a distinction between the internal and the external IP address is always possible. The internal address is only of local importance and is needed for communication in your own network. As soon as the device communicates via a router on the Internet, the router assigns the terminal external IP address.

This has the provider assigned to the Internet connection and it is unique worldwide. The device can be reached from anywhere via this external address. The internal IP address is usually not visible to other Internet subscribers.

It’s not that easy with the internal addresses. In Windows 7, for example, under Control Panel – Network and Internet – Network and Sharing Center you have to select your own Internet connection by clicking on the corresponding link and then selecting “Details”.