What is an IP address?

What is an IP address?

An IP address is a unique numerical combination that identifies a device in a local or global network. The English abbreviation “IP” can be deciphered as “Internet Protocol”, which is a set of rules according to which information is transferred.

Briefly, an IP address can be thought of as a personal identifier, without which a computer, router or smartphone will be invisible to other devices connected to the network. What other functions do IP addresses perform? What categories are they represented in?

General concept

An IP address for a network device can be compared to a residence permit or a phone number for a person. Each device is assigned a unique numerical combination that ensures correct detection and identification. Currently, the two most common versions of addresses are IPv4 and IPv6.

IPv4 – Internet Protocol version 4 – is a fairly old development, dating back to 1981. It is written in a 32-bit format, a typical example is “82.123.6.170”. The range of numbers between the dots is from 0 to 255.

IPv6 is a more modern alternative to IPv4, which appeared in 1996 and assumes a 128-bit writing format, which uses not only digital but also alphabetic characters. An example is “2044:0da3:11a4:01d3:7f72:6a3e:15a2:524d”.

The number of IP addresses of both types is limited. In the first case, it is slightly more than 4 billion, which is not enough for the Internet at the current stage of its development. Moreover, in 2019 there were no free IP addresses of this format left. All identifiers are occupied, new users have to wait until a suitable combination becomes available. It was the problem of IPv4 shortage that became the main reason for the emergence of IPv6. The maximum number is orders of magnitude greater, on average, there are more than 300 million possible identifiers per user. This technology meets the needs of communication systems for several decades to come.

Digital combinations are not generated randomly. The creation and distribution of IP addresses is handled by IANA, which is part of the ICANN structure, an American corporation founded in 1998, dealing with Internet security and accessibility.

Main functions

The main tasks that can be solved using IP addresses are as follows:

• Identification of network devices. Correct identification of equipment is important for both ordinary users and administrators, it helps to record problems at early stages of occurrence, block suspicious connections, and eliminate the risks of unauthorized access to resources.
• Routing of information transfer. Efficient operation of the network is possible only if data is transferred along the fastest paths. Routing analyzes the IP addresses of devices establishing a communication session, determines how to transfer data along the shortest path, eliminating possible failures and delays.
• Providing access to remote network resources. An IP address allows you to easily connect to a server regardless of its geographic location, download all the necessary information from it.

How it works

Understanding the algorithms of operation and interaction of IP addresses is useful for troubleshooting some network problems and connection issues. The following points are fundamental in these processes:

• Indirect connection of a user device to the Internet. This scheme implies that there is an auxiliary, intermediary network between the device and the global network. It is created by the provider or the work organization, depending on who exactly is trying to connect, who is authorized to service the network infrastructure.
• Assigning an individual IP address to the device.
• Exchange of information, sending commands, search queries from users, processing them by the provider, transmitting response data.

IP address structure

The easiest way to understand the structural features is using the example of an IPv4 IP address. As mentioned above, it is formed by four numbers with dots between them. The permissible range of numbers is from 0 to 255, which corresponds to an 8-bit system. Of course, the data is not determined randomly, but according to strictly defined algorithms, which provides the ability to navigate the network. The main structural components of the address look like this:

• Network number. It is indicated by the first 3 numbers. They can be used to determine which network the identifier belongs to and what its position is. Belonging to the same network allows a pair of identifiers to exchange data directly, otherwise an intermediary device, such as a switch or router, is required. The second function of the “intermediary”, which has its own IP address, is the most accurate distribution of messages across different networks in accordance with the specified instructions.
• Host number. This is an identifier assigned to a specific network device. It is encrypted in the last address number.

The IPv4 format assumes that a maximum of 256 devices can operate in the network. When building a larger system, you will have to use subnets.

IP Address Classification

IP addresses can be cataloged by various indicators, be it public access, anonymity, or duration of use. For example, from the point of view of public access and the ability to maintain confidentiality, two main groups are distinguished:

• Internal, or private. Each device connected to the local network has its own private IP address. The identifier cannot be found on the global network; its creation is the task of the router. The uniqueness of the numerical combination is relevant only within the local network, in other systems of a similar scale exactly the same values ​​can be used, confusion is excluded due to the lack of the possibility of intersection.
• External. In some sources such IP addresses are defined as public, publicly available. The provider is responsible for distribution, the identifier is not a secret and can be recorded by other network users.

An additional classification is valid for public IP addresses:

• Static. They are used by a strictly defined network device, do not change upon repeated connections. In terms of prevalence, they are somewhat inferior to dynamic ones. Such identifiers are used, for the most part, by server owners. The immutability of the address is a guarantee of quick and accurate detection by other devices connected to the network.
• Dynamic. They are regularly adjusted, remain relevant only for a certain period of time. The generation is random, the main principle is the absence of repetitions, so that each device can be assigned a personal identifier. The frequency of changing such an IP address is determined by the provider's policy, an adjustment is allowed after each communication session, or after a time interval, be it a day or a week. Redistribution of addresses helps the organization providing network access services to reduce costs, as well as increase the overall level of network security, regular changes make tracking and hacking difficult.

Network scale

The IP address can also determine the structure, configuration of the network it represents. The classification in this case is as follows:

• A. These are very large, global networks. The network number is fixed in the first number of IPv4, the rest fix the host number. The interval for the first number is from zero to 127.
• B. Medium-sized networks. The network number is fixed in the first two numbers, the other pair is the host number. The group of medium-sized IP addresses is from “128.0.0.0” to “191.255.0.0”.
• C. Small networks, the numbers of which are encrypted in the first three numbers. The maximum number of network devices that can be included in the structure is 256. Such IP addresses are typical for home networks, private company systems, small offices.

Specialized IP addresses

There are also special IP addresses that are needed not for addressing and ensuring stable network communication, but for solving some professional, administrative tasks. They look like this:

• 127.0.0.0 – localhost, thanks to which the network device addresses itself.
• 192.168.0.1 – identifier used on some network equipment. An example is a wireless router, which must be managed through the administrator panel, which opens through the browser. There may be some variations of the last two numbers, depending on the model and specification of the device.
• 10.0.0.0 is the address of not routers and routers, but other devices connected to the network, such as smart speakers, TV panels with SmartTV function, various peripherals.
• 255.255.255.255 and 0.0.0.0 are opposite addresses, similar in general specificity. The first IP address is broadcast, that is, the stream of transmitted data is available to all other devices connected to the network. Four zeros is the base address, indicating that there is no addressee, but it can also be used to make the server accept information from all devices connecting to it.

Connecting with DNS

Visiting various sites on the Internet involves entering not IP addresses, but URL addresses, the connection between which is provided by DNS, the domain name system. The algorithm of interaction between IP and DNS looks like this:

• The browser sends a URL to the DNS server.
• The server checks whether the address is registered in the general database.
• If the check shows a positive result, the DNS server sends the browser the IP address of the network resource being searched for.
• The address is redirected to the organization providing network access services, which allows for a successful connection to be established and information exchange to begin.

Each provider, as a rule, uses its own DNS servers that interact with global ones. To reduce the time required to process requests, caching technology is used, eliminating the need to constantly download the same information.

Do you need to know your IP address?

Overall, this is very useful information. For example, knowing the external identifier allows you to establish the following:

• Detailed information about the organization providing Internet access services, the provider.
• The legality of use and “cleanliness” of the IP address, so that it does not end up on block lists, does not even indirectly relate to fraudulent activity, spam mailings, hackers.
• Remote connection. For example, fans of online games, opening a server on their own computer, must share external IP addresses with other players to connect.

The internal address will also be valuable. This will help to check the devices connected to the router, if necessary - block suspicious connections, disable unverified equipment that does not inspire confidence.

How to check the IP address?

Microsoft Windows users can get the necessary information, for example, through the command line. The algorithm of actions is as follows:

• Press the “Win+R” combination on the keyboard.
• Enter the “cmd” command.
• Enter the “ipconfig” command, after activating which all information regarding the connection will be displayed.

On MacOS, the process is even simpler - just open the system settings section and open the “Network” item, where the required data is located. However, users have access not only to system tools, but also to alternative services. They are universal, suitable for any OS, and completely free. A popular example is 2ip.

Network Security and IP Address Protection

Unfortunately, knowing the IP address opens up some opportunities for scammers. They can use this information to perform the following illegal actions:

• Tracking the victim's network activity. Data on visited sites, comments left, becomes public, which can be used for blackmail, determining the actual address of residence.
• Uploading illegal content. Fraudsters will not upload content that violates the law to the network from their own IP addresses, for this they use the victim's identifiers. You can face copyright infringement law, or even more serious offenses, some of which involve criminal prosecution. The victim will have to spend a lot of time and effort to prove their innocence.
• Hacker attack. A common example is a DDoS attack on a website. The network resource receives huge numbers of requests that it simply cannot process correctly, law-abiding users cannot access the site, all services are blocked. For commercial organizations and online trading platforms, this is fraught with serious losses, financial and reputational.
• Hacking equipment. Knowing the IP address allows a hacker to hack the ports of the victim device to gain access to all information stored on it, including confidential information, and install malicious software.

Countermeasures include the simplest network security rules, ignoring unverified, suspicious sites, links and files, using licensed antivirus applications from trusted developers, and timely updating of databases.

One of the most reliable options to avoid unnecessary troubles is to use VPN, intermediate servers that act as intermediaries in communication sessions, hiding actual user IP addresses. It is highly recommended to use proven VPN services when connecting to public Wi-Fi networks, remote work, frequent interaction with commercial information, bank card numbers, accounts.

Author of the article:

Editor-in-Chief

Danaev Almaz