What is an IP address?
An IP address, or Internet Protocol address, is a unique number assigned to every device (PC, mobile phone, router, etc.) on a computer network and used to communicate with each other and the internet. If you, for example, give Google a request on "What is a VPN?" your IP address sends it to Google’s servers, finds an answer, and sends it back to you, using your IP to address you.
Structure of an IP address
The structure of an IP address depends on its version: IPv4 or IPv6. IPv4 is the most commonly used version of IP addresses and consists of a 32-bit binary number, composed of four groups of eight bits, separated by dots. Each section comprises one to three digits that fall between 0 and 255. Such a structure gives approximately 4.3 billion possible unique IPv4 addresses.
IPv6 is the most recent version of an IP address, initiated in 1995. It consists of eight groups of four hexadecimal digits separated by colons. Each digit represents four bits and allows for a much larger number of IPv6 combinations than IPv4.
Types of IP addresses
Types of IP addresses depend on their version (IPv4 and IPv6), availability, usage, and the purpose of the IP address assignment.
Both versions, IPv4 and IPv6, can be divided into public and private IP addresses, which are used for different purposes:
- Public IP addresses are assigned to a device by the internet service provider (ISP) and are used to identify the device on the public internet.
- Private IP addresses are assigned to devices on a private network, such as a home or office network.
IP addresses are further subdivided into dynamic and static IPs:
- Dynamic IP addresses change at set time intervals and are usually assigned by the ISP to a device when it connects to the internet.
- Static IP addresses remain the same over an extended period and are often used for services that require a consistent address, such as hosting a website or running a mail server.
Let’s look at all these types of IP addresses a little more closely.
What is a private IP address?
Private IP addresses are used in private networks for seamless internal device communication and are provided by an ISP, router, or server using the dynamic host configuration protocol (DHCP) process. Private IP addresses are not routable online and are only used within private networks.
RFC 1918 specified a private address space of IPs reserved for internal networks:
- 10.0.0.0 — 10.255.255.255 (10.0.0.0/8)
- 172.16.0.0 — 172.31.255.255 (172.16.0.0/12)
- 192.168.0.0 — 192.168.255.255 (192.168.0.0/16)
Because private IP addresses are only used within a single private network, they’re not exposed to cyber threats lurking on the public internet. Another advantage of private IP addresses is that the same combination of IPs can be reused on different private networks, efficiently using the IP address space.
On the other hand, private IP addresses are not so convenient for connecting to the internet and require network address translation (NAT) or a virtual private network (VPN) to access the public internet directly.
What is a public IP address?
Public IP addresses are unique numerical combinations your router uses to communicate with the internet. They’re assigned to you by your internet service provider (ISP) and supervised by regional internet registries (RIPs). If you use multiple devices connected to the same network, they will all share the same public IP address.
A public IP address helps your router communicate with the devices across the public internet and changes every time you connect to the internet when a dynamic IP is used. However, some ISPs provide static IPs that don’t change and are used for tasks like hosting websites, running a server, or port forwarding.
The association between your public IP and your identity raises concerns about privacy and security. Using this information, snoopers and internet service providers can track and monitor your online activities. Moreover, this may cause unauthorized access to your systems and cyberattacks because public IPs are routable within the public internet.
Two types of public IP addresses
The efficiency of your network usability can strongly depend on what type of IP you use. Let’s look at static and dynamic IPs:
What is a dynamic IP address?
A dynamic IP address is the most commonly used IP address and the default issued by the ISP. They’re easy to manage and don’t require much technical knowledge to run daily tasks. You get a new IP address every time you connect to the internet, which increases your cybersecurity.
This type of IP is used in most households for personal computers and mobile devices that don’t require a consistent IP address.
What is a static IP address?
Unlike private IPs, static IP addresses require extra setup and an additional fee. They’re manually assigned by a Dynamic Host Configuration Protocol (DHCP) server to a device or a network and does not change. They’re typically used for tasks requiring a consistent IP to run tasks like website hosting, server running, remote access, or port forwarding.
However, even though static IPs provide stability, they’re more vulnerable to security risks because they never change, and your identity is easier to disclose.
Differences between a dedicated IP and a shared IP address
There are two types of IP addresses that can be used by websites or online services: dedicated IP addresses and shared IP addresses. Here are some of the key differences between the two:
- Ownership. A single user owns a dedicated IP, while a single shared IP can be used by multiple users simultaneously.
- Usage. While a dedicated IP is only used by a single device, a shared IP may be attributed to multiple devices to perform shared hosting tasks.
- Reputation. Dedicated IP’s reputation is only determined by a single user, while a shared IP’s reputation can be affected by multiple devices and users that share the same IP activity.
- Cost. A dedicated IP is often more expensive than a shared IP because it requires a separate assignment and management.
Seeking even more security? NordVPN offers Meshnet as an IP routing alternative instead of a dedicated IP. With Meshnet, you can connect multiple devices for remote access and route your traffic through any of connected devices. For instance, by adding your home computer to Meshnet devices, you can access it remotely using your home IP address while at work or on vacation.
Subnetting
Subnetting is a strategy used to divide a large network into smaller subnetworks, or subnets. This technique lets network administrators improve network performance, increase security, and manage network resources. During subnetting, a subnet mask is created to define the network and host portions of an IP address, allowing the admins to assign an IP address for subnet devices, reduce network traffic, and conceal network complexity. Subnetting is a widely used concept in networking that eases cloud computing and day-to-day tasks for enterprises or data centers.
Other types of IP addresses
In the realm of IP addresses, other types of IPs play unique roles in network communication and ease the processes of gaming, streaming, or data sharing. These include:
- Multicast IP. This is a unique kind of IP address used when one device needs to send the same piece of data to several devices at once. It’s kind of like sending one message to a group chat. You’ll find multicast IPs at work during activities like video streaming and online gaming.
- Broadcast IP. When data needs to be sent to every single device on a network, a broadcast IP is used.
- Default gateway IP. This is your router’s IP address, which connects your network to the internet. When your device wants to send information to another network, it sends it to the default gateway IP, which then forwards it to the correct destination.
- Local host IP. This special IP address is a way for a device to refer to itself. The local host IP is often used to test network services without sending data onto the network.
What IP type do I get when I use a VPN?
A common practice for premium VPN providers like NordVPN is to assign you a shared IP address. Privacy-wise, it’s the best option. Multiple users share it, making it more difficult for websites to track you. A shared IP is also great if you travel a lot, because it can help you access the content that might be censored in the country you visit.
On the other hand, a shared IP can have a "bad neighbor effect," which means that if someone using the same IP gets blocklisted on a particular website, you won’t be able to access it either. However, this is a rare occurrence. The worst inconvenience you might face is more captcha requests than usual – when sites try to prove you aren’t a bot.
However, if you wish to get your own IP, follow these instructions on purchasing a NordVPN dedicated IP.
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