What is an IP address (Internet Protocol address)?
IP addresses are unique numerical identifiers for devices or networks that connect to the internet, assigned by an ISP. They are used to communicate across the internet. for communicating across the internet.
IPv4 and IPv6 are two versions of IP addresses commonly used on the internet. IPv4 is a set of four dotted decimal numbers separated by a period, while IPv6 is a set of eight groups of four hexadecimal digits separated by colons. An IPv4 address is composed of three digits representing a particular network on the internet, while an IPv6 address is composed of four hexadecimal digits separated by colons.
IP addresses can send data to other IP addresses through packets, which contain the data and a header with metadata.
How do IP addresses work?
IP addresses are part of the TCP/IP suite of protocols, helping devices and websites connect on the internet.
The IP address is an important part of the process of accessing a website. The requesting computer connects to the network router, which then connects to the web server where the website lives. The web server then pulls the website information and sends it back to the requesting computer. Each device in this process has a uniquely identifiable IP address, without which the transfer of information will not take place.
Pv4 vs IPv6: What’s the difference?
IPv4 and IPv6 identify connected devices on the network, but have slight differences in how they operate. IPv6 was introduced to address the limitations of IPv4.
The following is a list of differences between IPv4 and IPv6:
- IPv4 is 32-bit, whereas IPv6 is 128-bit.
- In IPv4, binary bits are separated by a dot (.); IPv6 separates binary bits by a colon (:).
- IPv4 follows the numeric addressing method and IPv6 is alphanumeric.
- IPv4 offers 12 header fields and IPv6 offers eight header fields.
- IPv4 has checksum fields but IPv6 doesn’t.
- IPv4 supports broadcast address, which is a type of special address that transmits data packets to every node on the network. IPv6 doesn’t support broadcast, but instead uses a multicast address, which is a logical identifier for a collection of hosts on a network.
- IPv4 supports Variable Length Subnet Mask, but IPv6 doesn’t.
- When mapping to media access control addresses, IPv4 uses the Address Resolution Protocol. IPv6 uses the Neighbor Discovery Protocol, which uses stateless auto-configuration and address resolution.
Types of IP addresses
The five most common types of IP addresses are listed.
1. Private IP addresses
Private IP addresses are non-internet facing and only used on an internal network. They can be found on devices such as computers, tablets, smartphones, Bluetooth devices, smart TVs and printers. With the increasing popularity of internet of things products, the use of private IP addressing is likely to continue to grow.
2. Public IP addresses
ISPs assign public IP addresses to routers, which enable them to communicate with the internet or an outside network. Multiple devices sharing the same connection will also share the same public IP address.
3. Dynamic IP addresses
ISPs buy large pools of IP addresses to assign to their customers automatically, resulting in cost savings and easier network management. Dynamic IP addresses also offer security benefits, as it is harder for cybercriminals to hack into a network interface if its IP is constantly changing.
4. Static IP addresses
Static IP addresses are essential for businesses that wish to host their own web servers. They ensure that all websites and email addresses associated with a certain web server will always have a consistent IP address so they can be reached on the internet. Most internet users and businesses don’t require static IP addresses, but they are a requirement for businesses that wish to host their own web servers.
5. Website IP addresses
Website IP addresses are for website owners who don’t host their websites on their own servers, composed of two types: static and dynamic.
- Shared. IP addresses are shared among many websites and are mostly used by small businesses using a managed hosting service.
- Dedicated. IP addresses are unique IP addresses assigned to an individual website, helping owners avoid being blocked or blacklisted. They also allow owners to access their websites while waiting for a domain transfer.
Looking up an IP address
The simplest way to look up an IP address is to type “what is my IP address?” into an internet browser, which will return the public IP address of the requesting device.
Windows 10 and Windows 11
- Select Start>Settings>Network & internet>Wi-Fi and the Wi-Fi network you’re connected to.
- Under Properties, look for your IP address listed next to IPv4 address.
- Go to System Preferences.
- Select network. This should show the IP address information.
- Go to Settings.
- Select Wi-Fi and click on the information icon, which is the blue “I” in a circle to the right of the connected network.
- The IP address should be visible under the Dynamic Host Configuration Protocol (DHCP) tab.
Various websites, such as whatismyipaddress.com, also automatically find the IP address of a device.
IP address security
Cybercriminals can exploit an IP address in various ways, so it is important to keep it as private as possible. To do this, it is best to hide the IP address and access the internet securely through a virtual private network service or a proxy server or browser, such as Tor, that anonymizes web traffic.
Here are some ways cybercriminals can exploit a stolen IP address.
- Download illegal content. Cybercriminals often use stolen and unprotected IP addresses to access and download illegal content. This way they avoid being tracked, as the IP addresses are traced back to the IP address owners.
- Location tracking. Most public addresses can be used to narrow down someone’s physical location, such as their city of residence. With some digging, criminals can even locate the actual home address of an IP address owner.
- Distributed denial-of-service attacks. By obtaining an IP address, criminals can carry out targeted DDoS attacks against a network. During these attacks, massive amounts of fake traffic is generally sent to a website to bring it down.
- Send spam. Advertisers can embed tracking programs in online activities and articles that can record IP addresses. The recorded IP addresses are used to generate spam and to target advertising based on a visitor’s browsing history.
- Steal identity. Identity theft is on the rise and cybercriminals are always on the lookout for personally identifiable information (PII), such as social security numbers or mailing addresses. While an IP address isn’t technically PII, it can help a cybercriminal gain access to other information. For example, if a cybercriminal obtains a person’s IP address, they can easily track down their ISP and attempt to impersonate them through vishing attacks that can cause the ISP to divulge personal data.
Network administrators must choose between static and dynamic IP addresses to configure a network. Learn the pros and cons of each.