Internet and security: what can someone do with your IP address

The Internet is an amazing thing, which gives plenty of possibilities to everyone who is willing to take advantage of it. At the same time, it is the place where everything is constantly monitored. And the IP address is often the key to understanding how the process of surveillance works. So let’s dive in and see what an IP address is and what someone can do with your IP.

An IP address: what is it?

IP stands for Internet Protocol, an essential technology which is responsible for addressing and routing packages across networks. IP addresses allow devices to transmit data to the correct destination. No matter if it is communication between your printer and laptop in the local network or your web browser and a web server on the Internet.

There are two main varieties of IP addresses – IPv4 and IPv6. IPv4, the very first type of IP address, was invented in 1980 and is essentially a 4-byte number. It consists of four decimal numbers separated by three dots, where every number is actually a byte. For instance, 127.0.0.1 (called localhost) is an IP address used to point the software to the currently used machine.

The quantity of IPv4 addresses is limited to ≈4B, which is not enough to cover all addressing demands of the modern Web, as the number of connected devices increases rapidly, and currently amounts to tens of billions of different devices all over the world: servers, computers, mobile phones, smart (Internet-of-Things) devices, and so on. IPv6 was created to solve this issue. It uses 128-bit numbers for addressing and provides a huge address space. Visual representation of an IPv6 address is a bit different, for instance your localhost address would look like ::1.

Differences between public and private IP addresses

There are two main kinds of IP addresses – public and private IPs. Devices use private IP addresses to communicate between each other in local networks. If a user assigns it manually, this is a static private address IP. On the other hand, more often private IP addresses are assigned to devices automatically by your ISP using DHCP protocol. Private IP addresses (often looking like 192.168.xx.xx or 10.xx.xx.xx) are used only within local networks and won’t be of help to route data globally on the Internet.

To transmit your data successfully back and forth through the Internet, at some stage the private (i.e. not globally routable) IP address of your device should be replaced with a public (globally routable) IP address. Here is how this process works:

1. All devices on your local network connect to the router, which already has an IP address assigned by your Internet Service Provider (ISP).

2. The router uses a built-in Network Address Translation (NAT) service, which allows a router to act as a gateway between the Internet and a local network. This means that a group of devices can be represented by a single, unique IP address.

3. The gateway sends all outgoing traffic on its behalf, remembers exactly who sent it, then receives a response and returns it to the sender.

There can be more layers (double NAT) in this process, so more of an outline rather than an exact description of what happens.

Public IP addresses are allocated by ISPs and may be static (staying the same indefinitely, usually used for servers) or dynamic (changing from time to time). Public IP addresses do not reveal sensitive personal information like phone numbers, names, or exact addresses per se. However, there are harmful things that people can do with your IP address.

What is the IP address of my device?

The way you can find your IP address depends on your device and the operating system you use:

Windows:

• In the start menu search for the command prompt (cmd) and open it.
• Type in the command prompt ipconfig /all and press enter.

Mac:

• Tap Apple
• Choose System Preferences and then Network
• In the left menu select the active connection, the one with a green dot next to it.
  The private address will be displayed on the right in the Connection section.

Linux:

• Open the command line.
• Type ifconfig and press enter.

Android:

• Open Settings and find Connections.
• Tap the gray icon to the right of the name of your Wi-Fi connection.

iPhone:

• Go to Settings and tap Wi-Fi.
• Click on “i” with a circle near your network.

Depending on the type of connection, you can find a private IP address or a public one. However, usually it's a private address received by a device inside the local network. You can find information about your public IP address on various external resources like this website.

Is it Illegal if someone searches for your IP address?

Every time you connect to the web, you show your IP to websites you visit and service providers you use (including mobile app owners). Tracking IP addresses is legal for marketing purposes. And companies freely use this method of gathering data to improve their business, sell more products, and receive higher revenue.

However, individual users also might track your activity via your IP. There is no law that prohibits individuals snooping on your IP address. In a general sense, finding out the IP address itself is not unlawful. At the same time, many illegal things that someone can do with your IP, including hacking, spear phishing, and online stalking, rely on knowing the victim's IP address. Besides that, storage and processing of IP addresses may be legally regulated (see GDPR, for example) if they are a part of personal information.

How someone can learn your IP address

In reality, finding your IP address isn't a hard task. Here are some methods, which can be used to detect your IP:

Emails. Email clients automatically put the user's IP address in the email headers. Hackers only need to check the header to learn your IP address if you send them an email. In recent years, major mail services have changed the way they handle IP addresses and have started to hide them. However, be aware of this method of getting IP addresses and don’t send emails to untrusted contacts.

Suspicious links. Another popular way to find out your IP is to send you a link to some website or picture controlled by a cybercriminal by email or through any messenger. After you follow the link, your IP address will be in their hands.

Torrenting. When you send or receive data via torrent network, your IP address is visible to other participants of this network. Some of them may be parties involved in data mining or representatives of copyright holders tracing the IP addresses of copyright infringers.

What can someone do with your IP address?

Ok, we determined how bad actors can get hands on your IP address, but what are the actual threats once that has happened?

Track your online activity

Your ISP, government, web services, websites, and even your employer can use your IP address to collect your digital footprints and monitor your online activity. IP addresses allow companies to gather and store on their servers plenty of users’ data for different purposes. Furthermore, data servers can be vulnerable to data breaches and often become the target of cybercriminals.

Access your geographic location

Your IP address reveals information about your ISP’s name and general geographic location with the accuracy of a city or even a district. Knowing a more complete history of changes in your IP address, it becomes easy to draw up your daily routine, determine when you are at home or at work, and track when and where you left for vacation. Of course, to pull it off attackers need a way to permanently track your IP address. However, it’s not an impossible task. This information can be collected as a result of a purposeful and targeted attack on somebody, or become public because of a data leak.

Bombard you with annoying ads and personalized spam

Geotargeting uses IP addresses to deliver ads based on the country and city. Every time you see ads related to the place you live, know this is geo-targeting. Marketers widely use this method, but it doesn't allow them to identify a single individual to target. However, advertising technologies and additional sources of data help create a detailed profile of a user and set up ads with surgical precision, IP address being a vital part of it.

Hack your device

It may be a requirement of a home VPN server or a smart home system to have a public IP address and allow incoming connections from outside. If the device that receives connections is not well protected or contains vulnerabilities, a potential hacker can hack into your network or device by knowing the IP address.

Carry out DOS or DDoS attacks

Knowing your IP address it’s also possible to execute denial of service (DOS) or distributed denial of service attack (DDoS). DOS attacks block access to the network resources, websites, accounts, and emails. This is possible because of overloading and disabling users’ systems by sending a lot of server requests to the user's address. DDoS attacks are similar, except that multiple machines are involved, making the traffic even heavier.

Snoop on you

Knowing how your IP address changes during the day or over the week, it’s possible to create a full picture of your usual everydays activities, for example, when you leave home, return back, and which places you like to visit in your free time.

Get access to your security cameras

You are at risk if you have security cameras connected to the Internet. Hackers might guess or reset your device’s password, take advantage of software vulnerabilities and finally get access to the video.

How to protect your IP address

In order to protect your IP address, you can take the following steps:

Update your router settings

The first step to enforce your protection is to check your device settings and change the administrative password on your router. Often default passwords are easy to hack and this method is widely used in cyber attacks.

Set up a firewall

A firewall helps you protect your network by blocking suspicious incoming traffic and connections. If you have a public IP address – it’s important to make sure that no ports are open except those you specifically want to keep open. Not doing this brings risks of unauthorized access to your network.

Correctly configure your software accessible from the Internet

In addition to the previous point, if you have a public IP address, it’s better to make sure that software accepting incoming connections does not allow non-authorized access (guest accounts are disabled, passwords are strong enough, etc) and does not have publicly-known vulnerabilities. Otherwise one day you’ll face the fact that somebody broke into your network exploiting that software.

Use an ad blocker

Using an ad blocker significantly reduces the amount of information that trackers and data mining companies can gather about you.

Do not click on links in suspicious emails

Remember that emails are often (more often than other means of communication) used for phishing and targeted attacks. The links inside them may lead to malicious websites which try to steal your data, infect your computer with viruses or gather information about you.

Hide your IP address with a VPN

VPN is the most popular, effective, and easy-to-use method to hide your IP address. VPN users need only to turn on the VPN and browse the web as usual. All online traffic reroutes in an encrypted tunnel through a VPN server, which automatically changes the current IP address to the IP address of the selected VPN server.

Use Tor Browser

Tor Browser is often associated with something shady and suspicious because it’s the only way to access the dark web. But even if you don't have such goals, you can freely use Tor for more anonymity online. The browser passes all your online traffic through a chain of three different proxy servers (called nodes, or relays) and hides your real public IP address. Also, Tor encrypts online activity and lets you surf the Internet with higher levels of anonymity and security. However, the main disadvantage is that Tor dramatically slows down your Internet connection, and due to this is virtually unsuitable for downloading, gaming, and watching streaming videos.

Why AdGuard

VPN is one of the most popular cybersecurity tools to protect your IP from all harmful things that might happen if someone learns your IP address. If you are ready to benefit from using a VPN, take a look at AdGuard VPN and its advantages:

In-house developed VPN protocol. A lot of VPN service providers use ready solutions. AdGuard released a proprietary protocol, which is more difficult to detect and is faster than its analogs.

Customizable modes. There are two different modes in AdGuard, which users can customize according to their preferences. The first mode allows adding web sites, where VPN will work. On the other hand, the second mode contains the list of websites for which VPN will be disabled.

Split tunneling. The samefeature as described above, but designed specially
for applications.

DNS server of your choice. Usually, VPN users have to rely on the DNS server provided by their ISP. With AdGuard VPN you can choose a DNS server from known DNS providers or configure your own DNS server.

Locations with the fastest speed. AdGuard VPN users can select a server location based on its ping, or, in other words, the time needed by a data packet to reach the server and return back to your device. When you choose the server with the lower ping, you select the server that is closest to you, and therefore your internet connection speed is higher. AdGuard VPN continually increases the number of server locations for you to choose from.

QUIC support. QUIC is a high-performance protocol, which provides better connection quality in non-ideal conditions and helps users with slow Internet access.

Kill switch. Kill Switch is an essential VPN feature, which automatically disconnects you from the Internet if VPN connection suddenly drops. Without Kill Switch you might not notice this and continue browsing with an insecure connection and disclose your private information.

Auto-protection. This option automatically turns on AdGuard VPN when you connect to unsecured networks. It allows AdGuard VPN users to stay safe while using vulnerable public Wi-Fi networks.

Simultaneous connections. Premium AdGuard VPN users have no limit on the number of devices logged into the account and can have up to five VPN connections running simultaneously. Users without a subscription can use AdGuard VPN on up to two devices.

Secure streaming. Streaming services try to block VPN users because VPNs are often used to bypass geo-blocking. But the situation might be different. Users just want to be protected with a VPN when watching their country's content. Or not to lose the benefits of a subscription while traveling in another country. All this can be handled with AdGuard VPN.

Clear no-logs policy. AdGuard is a privacy-oriented company and does not store users’ activity logs. The company collects only minimal information required for the identification of technical issues and improving service.

FAQ

If you still have any questions left about IP addresses, this section will likely cover them.

What happens if someone has my IP address?

If you don’t use VPN or proxy, you reveal your IP address every time you connect to the Internet. Companies use information about your IP for marketing purposes. Hackers and intruders may use it to snoop on you, send you spam and phishing emails. Website owners may restrict access to certain services. Copyright owners may use your IP to prosecute you for copyright infringement if you download illegal torrents.

Should I be worried if someone knows my IP address?

If you are not a target of a personal attack against you — it will bear no harm. Otherwise, your IP address is a useful piece of information which could give intruders new attack vectors (like port-scanning your IP, figuring out your location, scanning public databases to match your IP with other personal data of yours).

Is it possible to change my IP address?

Yes, you can change your public IP address using a proxy or VPN. However, VPNs provide higher security, privacy, and protection.

Does unplugging your router change your IP?

It depends on how IP address lease is handled by your ISP. Sometimes this action would do just that, and sometimes it would not.

Does changing Wi-Fi spots change IP?

Yes, every time you connect to a different Wi-Fi network, your public IP changes to an IP of a gateway of that network.

Can someone spy on me with my IP address?

Yes, it’s possible to spy on you with your IP. Knowing how your IP changes during the day and week, it’s possible to build a complete picture of your everyday activities, for example, when you go to work, return home, or visit your favorite coffee shop. If you use a torrent network, it’s possible to find out what you download by simply knowing your IP. Moreover, knowledge of your IP addresses is a first step for hackers to remotely access your security systems and webcams, if you have any, and spy on you in real time.