What Is Internet Protocol (IP)? Working, Types & IPv4 vs IPv6

Internet Protocol (IP) is a set of rules that helps in sending data from one device to another across networks. Every time you load a web page or send a message, your data travels in small packets and IP labels as well as routes each one. It enables different networks to connect to each other and function together as the Internet.

In this blog, we will start by explaining what is internet protocol, how it works, and its core functions. We will also discuss how IPv4 differs from IPv6. We’ll also cover the main types of IP addresses, where IP fits in the TCP/IP model and real-world examples of IP.

What Is Internet Protocol?

Internet protocol is the internet’s addressing and delivery system. Other than addressing and delivering data, it doesn’t concern itself with what is being sent. A picture, an online payment, and a voice call, to the internet’s way of thinking, are all the same. They are all just chunks of data.

IP’s responsibility is to affix a source address and a destination address to a packet and send it off. Routers read that address and forward the packet along to the next router. This continues until the packet reaches its destination.

IP also skips a lot of details. It’s not concerned with whether the packet arrived or whether it arrived in order, because TCP handles that. IP is just concerned with moving packets with a “best effort” strategy. Internet protocol is perhaps the most fundamental internet protocol. Understanding it is key to understanding other, related protocols.

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How Does Internet Protocol Work?

The following steps explain how IP helps deliver data when you open a website:

1. Your Data Gets Split: A request is sent from the browser and arrives at the transport layer where it is broken into smaller pieces by TCP or UDP.

1. IP Encapsulates the Data: Each piece is wrapped by IP, and a header is added that shows the source and destination IP, the TTL, and the protocol. Each of these is now known as an IP packet.

1. Packets Leave Your Network: The packets leave your network and arrive at your Internet Service Provider (ISP). On most home setups the ISP also swaps your private address for a public one by NAT.

1. Routers Forward Packets: Packets take different paths based on the request. Along the way, each router makes a decision on the next hop based on the routing table and the destination address.

1. TTL or Hop Limit Helps Prevent Loops: Each time a packet arrives at a router, the TTL is decreased by one. If it hits zero, the packet is dropped.

1. The Destination Processes the Data: At the destination, IP delivers the payload to the appropriate transport protocol. If TCP is used, TCP reorders received segments as needed and provides a reliable byte stream to the application.

The server’s response travels back through the network to your device. The return path may differ from the path taken by the original request.

Key Functions of Internet Protocol

IP has a focused set of responsibilities that allow devices and networks to exchange data:

1. Addressing: Each network interface uses an IP address to identify a source or destination. Packets carry these addresses to help deliver data across networks.

1. Encapsulation: IP adds a header containing delivery information, such as source and destination addresses, to the transport-layer data.

1. Routing: Routers examine the destination IP address and consult their routing tables to select the next hop for a packet.

1. Fragmentation: IPv4 supports fragmentation by the source and, when permitted, by routers. In IPv6, only the source can fragment packets.

1. Loop Prevention: IPv4 TTL and IPv6 Hop Limit fields limit how many router hops a packet can traverse.

1. Error Checking: The IPv4 header includes a checksum that helps detect errors in the header. Routers discard packets with invalid header checksums. IPv6 does not include an IP header checksum.

1. Delivery Modes: IP supports unicast and multicast. IPv4 also supports broadcast, while IPv6 uses multicast instead of broadcast. Anycast sends traffic to one of multiple interfaces advertising the same address, with routing determining which destination receives it.

Types of Internet Protocol: IPv4 vs IPv6

The two widely deployed versions of Internet Protocol are IPv4 and IPv6. IPv5 was associated with an experimental Internet Stream Protocol and did not become a general-purpose successor to IPv4.

Internet Protocol version 4 (IPv4)

Defined in RFC 791, IPv4 is still carrying a considerable amount of traffic on the Internet. It uses 32-bit addresses, which allow about 4.3 billion combinations. The global free pool ran dry in 2011, so with the usage of NAT, IPv4 going ever since. 

Internet Protocol version 6 (IPv6)

IPv6, specified in RFC 8200, uses 128-bit addresses and provides approximately 3.4 × 10³⁸ possible address combinations. It’s much larger address space helps address IPv4 scarcity and supports continued internet growth.

In March 2026, 50.1% of users reached Google over IPv6, crossing the 50% milestone for the first time (Internet Society Pulse). Around 72% of users in India reached Google over IPv6.

Want to Learn More About IPv4 vs. IPv6? Read Our Detailed Guide. – IPv4 vs IPv6: Differences, Diagram, Features & Examples

Feature	IPv4	IPv6
Address size	32 bits	128 bits
Total addresses	About 4.3 billion	About 3.4 × 10³⁸
Format	Dotted decimal (192.168.1.10)	Hex with colons (2001:db8::1)
Header size	20 to 60 bytes	Fixed 40 bytes
Header checksum	Yes	No
Fragmentation	Sender and routers	Sender only
Address setup	Manual or DHCP	SLAAC or DHCPv6
Broadcast	Yes	No, multicast instead
Loop counter	TTL	Hop Limit
NAT	Widely used	Rarely needed

One Popular Misconception About IPv6: IPv6 was considered “more secure” because IPsec was part of the initial design. IPsec is optional in both versions today, so the real security comes from the configuration of the network.

Types of IP Addresses

There are different types of IP addresses, and these are the major ones you may encounter in networking:

1. Public IP Address: A globally reachable address used to communicate across the internet, subject to routing and security policies. Your internet service provider may assign one to your router or connection.

1. Private IP Address: An IPv4 address reserved for use within private networks. The private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. These addresses are not routed across the public internet.

1. Static IP Address: An address configured to remain fixed, either manually or through a DHCP reservation. Servers, cameras and network equipment may use static addressing where appropriate.

1. Dynamic IP Address: An address assigned automatically and potentially changed over time, often through DHCP.

1. Loopback Address: A loopback address is 127.0.0.1 in IPv4, or ::1 in IPv6, and is used for testing communication within the local device.

You can check your IP address using the following commands:

1. Windows: Run ipconfig in Command Prompt to view network configuration.

1. macOS or Linux: ifconfig may be available, although ip addr is common on Linux systems.

1. Public IP Address: Use a trusted “what is my IP” service to find the public IP address visible to websites.

Internet Protocol in Computer Network: Where IP Fits

In any computer network, IP works at the network layer, which is Layer 3 in the OSI model and the Internet layer in the TCP/IP model.

When data is transmitted, it goes through this stack, and each layer adds a header to the data. When it’s received, it goes up this stack, and each part removes a header. Because of this layering, routers are concerned about IP addresses and switches are not. Switches move frames locally with MAC addresses and routers move packets with IP addresses.

IP usually works along with other protocols. These include:

1. TCP adds reliability and order to delivered data and is used for web, email, and other file transmissions.

1. UDP is used for video calls, games, and other real time data transmissions.

1. ICMP is used for checking and reporting errors and is used for the ping command.

1. ARP and NDP find the hardware addresses of IP addresses.

1. DHCP gives out IP addresses and DNS gives out names of addresses.

1. BGP and OSPF define the routes used by routers.

Real-world Examples of Internet Protocol

You interact with IP all day. Here are a few examples:

1. To load a web page: DNS resolution determines the web server’s IP, and your packets are sent to and from that IP address.

1. For a Video Call: VoIP sends voice and video over UDP, and if a packet is lost it is just skipped.

1. For a Ping Test: ICMP packets are used to check the availability of a host, and to assess how long it takes to respond.

1. For Public DNS Resolvers Such as 1.1.1.1 and 8.8.8.8: Both of these resolvers implement anycast, which means, any of their servers can answer your request, so you connect to the server that is nearest to you.

Drawbacks of Internet Protocol

Internet Protocol is designed to be simple and efficient. Many of its limitations are intentional, allowing higher-layer protocols to provide additional features when required.

1. No Delivery Assurance: Packets can be lost, duplicated or damaged during transit.

1. No Ordering: Packets can arrive out of order.

1. No Built-in Encryption: IP does not encrypt packet contents by itself. Privacy can be protected using technologies such as TLS, IPsec or a VPN.

1. A Shortage of IPv4 Addresses: NAT helps conserve public IPv4 addresses but can make direct device-to-device connectivity more complicated.

1. Address Spoofing: Source IP addresses can be forged in some situations, which is why network filtering and anti-spoofing controls are important.

These limitations help keep IP focused on addressing and packet forwarding. Higher-layer protocols can then provide the reliability, security and other features an application need.

Conclusion

Internet Protocol provides the addressing and forwarding system that allows packets to travel between devices and networks. Understanding its functions, address types and relationship with protocols such as TCP and UDP helps explain how internet communication works. IPv4 remains widely deployed, while IPv6 adoption continues to grow. Knowing how both versions operate helps network professionals configure networks, troubleshoot connectivity and apply appropriate security controls.

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FAQs About Internet Protocol

Q1. Is Internet Protocol the Same as an IP Address? 

No. Internet Protocol is the set of rules used to address and forward packets. An IP address is a numerical address used by those rules to identify a source or destination interface. 

Q2. Is IP Connection-oriented or Connectionless? 

IP is connectionless. It forwards packets without establishing a connection or session at the IP layer first. 

Q3. What is the Difference Between TCP and IP? 

IP addresses and forwards packets between networks. TCP operates at the transport layer and provides reliable, ordered delivery of a byte stream when used. 

Q4. Will IPv6 Fully Replace IPv4? 

IPv6 adoption is growing, but IPv4 is still in use. Many networks operate both protocols using dual stack, and both are likely to coexist for the foreseeable future.