What is an IP Address?

Definition of an IP Address

It’s essentially a digital equivalent of a mailing address or phone number for a specific device, such as a computer, smartphone, tablet, or server, when connected to the internet or a local network. 

The “Internet Protocol” itself is a set of rules governing the format of data sent over the Internet or other networks. The IP address is a crucial part of this system. Its primary purpose is twofold:

• Network host interface identification: This identifies the specific device or network interface that connects to the network.
• Location addressing: It specifies the use location of that device within the network system, allowing data packets to be routed to the correct destination.

Just as you need a correct mailing address to receive a letter, devices on the internet need a proper IP address to send and receive information.

Types of IP Addresses

Not all IP addresses are the same; they can be categorised in several ways based on their structure, scope, and assignment method. Understanding these distinctions is key to grasping how networks operate.

IPv 4 vs. IPv 6

This distinction is perhaps the most fundamental, with its use relating to the version of the Internet Protocol in use. Ipv4 (Internet Protocol version 4) is the older, traditional version with which you are likely most familiar. Ipv4 addresses are 32-bit numbers, typically written as four blocks of numbers separated by dots (e.g., 172.16.254.1).

This format allows for approximately 4.3 billion unique addresses. While that sounds like a lot, the rapid growth of internet-connected devices meant we quickly ran out of available IPv4 addresses – a situation known as Ipv4 exhaustion.

IPv 6 (Internet Protocol version 6): Developed to solve the address exhaustion problem, IPv 6 uses a much larger 128-bit address space for hosts. These addresses are written in hexadecimal notation, separated by colons (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334). This address format provides an almost unimaginable number of unique addresses, ensuring enough addresses for the foreseeable future of the Internet and the Internet of Things (IoT) devices.

Public vs. Private IP Addresses

There is a distinction related to how the IP address can be used as well. A public IP address is assigned to your network (usually your router) by your Internet Service Provider (ISP). It is globally unique and routable on the public internet, enabling your devices to communicate with websites, other devices, and VPN servers worldwide. Think of it as the main street address for your entire home or office network.

Private IP addresses are used within local networks (like home Wi-Fi or office LANS) and are not directly reachable from the public internet. Common ranges for private IPs include 192.168.x.x, 10. x.x.x, and 172.16.x.x through 172.31.x.x.

For most networks, it is not unlike the flat numbers inside a building – which would be unique inside the building but would only make sense if there is an associated main street number (the public IP) to interact with the outside world. Your router manages this translation using a process called Network Address Translation (NAT).

Subnet Masks

A subnet mask is a crucial component used alongside an IP address to define the specific boundaries of a network subnet within host networks. By designating which portion of the IP address represents the network and which represents the host, the subnet mask enables devices to determine if a target IP address resides on the same local subnet or if traffic needs routing to a different subnet.

Routers fundamentally rely on this mask to differentiate between subnets and direct data packets correctly across the network infrastructure and host networks. Proper configuration ensures devices within a particular subnet can communicate effectively and allows for the logical segmentation of larger networks into multiple, distinct subnets.

Also, with Classless Inter-Domain Routing (CIDR), notation relies on the forward slash or stroke. This slash, a diagonal stroke, is appended to an IP address. Following the stroke, a number indicates the network prefix length, clearly defining the boundary between the network and host portions of the address with the stroke.

Static vs. Dynamic IP Addresses

This section in the round describes how an IP address is assigned to a device. With a dynamic IP Address, these are assigned automatically, usually by a DHCP (Dynamic Host Configuration Protocol) server. The address is essentially “leased” to a device for a certain period every round.

Most home internet connections use dynamic public host IPs assigned by the ISP, as it's cost-effective and allows ISPs to reuse addresses efficiently. Your private IP addresses assigned by your router to devices are also typically dynamic every round. The main characteristic is that the IP address can change periodically (e.g. when you reboot your router or computer or around when the lease expires).

On the flip side, a static IP number is a fixed IP address that does not change. It's either manually configured on devices or permanently assigned by an ISP or network administrator. Static public IPs are often required for hosting servers.

How IP Addresses Work

Knowing an IP address acts like a digital address is the first step; understanding what and how it enables communication reveals the mechanics of the internet. The process relies on several interconnected systems guided by the Internet Protocol.

When you send or request information online, the data is first broken down into smaller pieces called packets that are in use.

Before your device sends packets, what it does is it queries a DNS server to look up the domain name and retrieve the corresponding public IP address of the destination server.

Once the destination IP address host is known and the packets are created, they are sent onto the network. Routers, acting as the internet's traffic directors or digital sorting offices, then take over.

Eventually, the packets arrive at the host networks of the destination server. The final router directs them to the specific server identified by the IP address.

In essence, IP addresses for devices provide the critical addressing framework allowing data to navigate the complex web of networks, while DNS makes it user-friendly and routers manage the journey packet by packet, enabling your virtual private cloud and VPN use - and allowing for plenty of VPN flexibility.

An IP address is a logical address for routing data between different networks, like a postal address that can change if you move. In contrast, a MAC address is the unique, physical hardware identifier burned into your network interface card; this MAC address typically never changes for that specific hardware.

The word "class" in the context of IP addresses primarily refers to the historical system of classful IP addressing. This system (using Class A, B, C, D, and E) was the original method for allocating IPv4 addresses and defining network sizes, but it has been largely superseded by Class-less Inter-Domain Routing (CIDR) since 1993 because it was inefficient and inflexible.

Benefits of Having a Unique IP Address

While every internet-connected network uses a public IP address that is secure and unique at any given moment, most residential users receive a dynamic IP from their Internet Service Provider (ISP), meaning the address can change over time.

In many discussions, the benefits of a "unique IP address" actually refer to the advantages of having a Static Public IP address (one that remains fixed) or, particularly in web hosting or when using dedicated servers, a Dedicated IP number (one not shared with other users or websites).

For everyday internet device use like browsing websites, streaming video, and online gaming, a standard dynamic IP works perfectly well. However, securing a static or dedicated IP offers significant advantages in several specific situations:

• Reliable hosting of services: If you intend to host your own services directly accessible from around the internet—such as a website, an email server, a game server, an FTP server, or specific applications—a static IP address is often considered essential for the devices and host networks. A static IP ensures your service remains consistently accessible at the same number.
   
• Enhanced security configurations (IP Whitelisting): Many security systems and firewalls allow administrators to configure access rules based on IP addresses. IP whitelisting, for instance, restricts access to a service or network only to connections originating from a pre-approved list of trusted IP addresses; it’s relevant for a VPN, too.
   
• Dedicated resources and reputation: In the context of web hosting, a dedicated IP address is what means your website or server does not share its public IP address with any other websites or customers on the same hosting platform. This avoids potential "bad neighbour" effects, where malicious activity (like sending spam or hosting malware) from another site sharing your IP could negatively impact your site's reputation or even lead to the IP being blacklisted, affecting your service. It provides a cleaner separation of resources to protect you.

While obtaining a static or dedicated IP address for use, networks often involve an additional cost from your ISP or private cloud hosting provider. The benefits of stability, reliability, and more secure operations can be crucial for businesses, individuals hosting services, or those requiring consistent remote access.

IP Address Geolocation

From a business perspective focused on expanding market reach, strategically utilising IP addresses with specific geolocations is essential for serving a broader range of customers effectively.

IP number geolocation fundamentally influences how online services are perceived and accessed in different parts of the online world; it allows systems to estimate a user's location and tailor their experience accordingly. It is not dissimilar to the purpose of a VPN, but without explicit use of a VPN.

For a company aiming to connect with international audiences or test or protect how its offerings appear in diverse markets, presenting a localised experience is key—this includes relevant languages, currencies, promotions, and content adhering to regional regulations or preferences.

To achieve this, businesses often employ secure servers, cloud resources, or specialised network services located within target geographic regions, thereby obtaining and utilising public IP addresses that geolocation databases associate with those specific countries or cities.

Troubleshooting Common IP Address Issues

In a hosting environment, addressing IP connectivity challenges is what is crucial for maintaining and protecting service uptime.

If a server fails to use its assigned IP after setup, review the deployment notes and check the network settings within the server's operating system configuration area. If addresses are assigned automatically on your internal network, consult the records of the assignment system. Also, ensure the secure server's network connection is active and linked to the correct network segment.

Errors or unstable connections can occur if two servers on the same network segment are using identical IP addresses. Network scanning tools can help identify devices using the same address. Check your internal IP address allocation records and correct the network settings on the server that has the incorrect configuration.

Finally, if a server's public address isn't accessible from the internet, first verify that the address is correctly activated on the server's network connection. Review the server's security software (firewall) settings to make sure they aren't blocking necessary secure traffic. Examine any broader network traffic rules or security filters applied within the hosting environment for protection.