What Is an IP Address?

What Is an IP Address?

IP is actually an abbreviation—it stands for Internet Protocol. It is a protocol that operates at Layer 3 of the OSI Model. It is 32 bits long, meaning it consists of 4 octets. Each octet takes a decimal value between 0 and 255. This applies to IPv4.

What Does an IP Do?

IP addresses enable packets to travel from one end to the other. It is a unique address that remains unchanged from the moment packet transmission begins. In short, it is our identification number—or even our fingerprint.

What Are Its Features?

• It is a connectionless protocol. When a packet is sent to its destination, it does not check whether the destination exists or not. At this stage, the ICMP protocol assists the IP protocol.
• It is a protocol that is independent of the medium through which data is transmitted. It does not matter whether the medium is air, fiber, or copper.
• It does not guarantee packet delivery. It does not concern itself with whether a packet has been sent or not, or even if it was sent in a corrupted state. There are other protocols that handle these matters.

IP Address Classes

When IPv4 addresses were first created, there was a class-based system. These classes provided different IP address ranges. The ranges were too large, and even a business with just 10 devices would end up with 254 IP addresses if it were assigned the smallest range. To solve this problem, the IETF phased out the class-based system and transitioned to CIDR.

Subnet Mask: Separates the network and host portions of an IP address. A subnet mask is required whenever an IP address is assigned or allocated.

Types of IP

IP addresses are divided into two categories: Public and Private:

• Public IP: These are addresses that are publicly accessible on the internet.
• Private IP: These do not connect to the internet and cannot be accessed from outside. For example, this type of IP is used for internal communication within military organizations.

Private IP ranges:

IPv6

Since IPv4 addresses are 32 bits long, there are 2³² possible addresses worldwide. As these began to run out, the IETF developed 128-bit IPv6 addresses. This capacity is so vast that, in theory, every light bulb in a home could be assigned an IP address. Currently, many large organizations are gradually transitioning to IPv6.