What Is an Internet Protocol? The Plain English Explanation
If you use the internet, you rely on internet protocols every single day, even if you don’t realize it. Whenever you check your email, stream a video, or browse social media, internet protocols make that communication and data transfer possible behind the scenes. But what exactly is an “internet protocol” and how does it work? This comprehensive beginner’s guide will explain internet protocols in plain English so you can better understand this fundamental internet concept.
The Role of Internet Protocols: Allowing Diverse Networks to Communicate
The internet connects many diverse types of networks and devices across the globe, from supercomputers to smartphones. An internet protocol provides a standardized set of rules that allows these heterogeneous networks and devices to communicate with each other effectively. According to Juniper Networks, “Communication requires that the sides be able to understand each other.” Internet protocols provide that common language and structure to facilitate communication regardless of differences in underlying hardware and software.
At a basic level, an internet protocol does two main things:
Breaks data down into packets: Data gets split into small chunks or “packets” that are transmitted independently. This allows large files to be broken down into bite-sized pieces that can traverse diverse networks and re-assemble at their destination.
Defines addressing and data transfer rules: Headers with addressing and other metadata enable proper routing and control. The protocol’s specifications dictate how sequence numbers, acknowledgments, error checking, and flow control will handle the data transfer.
By performing these two key functions, an internet protocol provides the indispensable oil that keeps the gears of internet communication turning smoothly. The two most prominent internet protocol standards are IPv4 and IPv6.
A Brief History of Internet Protocols
The origins of internet protocols trace back to research funded by the U.S. Department of Defense in the 1960s and 1970s. The DoD’s Advanced Research Projects Agency (ARPA) looked to design a resilient computer network that could withstand network outages. Researchers developed conceptual foundations like packet switching to route around failures and dynamically determine communication paths rather than rely on predetermined, static routes.
In the 1970s, network pioneer Vint Cerf played a leading role in developing the TCP/IP protocol suite that still underlies the modern internet. TCP (Transmission Control Protocol) handles data transport and IP (Internet Protocol) handles packet addressing and routing. TCP/IP provided interoperability between diverse networks from the early ARPANET to packet radio networks. By requiring hosts only implement TCP/IP to connect, this common internet protocol facilitated the internet’s explosive growth.
The current IPv4 standard dates back to 1981, while IPv6 came about in the 1990s to expand available addresses. We’ll look at both of these widely used internet protocol versions next.
IPv4 vs IPv6: Key Differences Explained
There are two primary standards for the Internet Protocol today—version 4 and version 6. Both perform the same basic internet protocol functions of addressing packets and handling data transfers between networks. However, IPv6 differs in some key ways:
Address Space: IPv4 allows for about 4.3 billion possible addresses while IPv6 provides a vastly larger address space of over 300 trillion trillion trillion addresses. The limited availability left under IPv4 has necessitated interventions like Network Address Translation (NAT) and spurred the eventual migration.
Address Notation: An IPv4 address consists of four decimal numbers ranging from 0-255 separated by dots, like 172.168.0.1. IPv6 uses eight groups of four hexadecimal digits with colons as separators, such as 2001:0db8:85a3:0000:0000:8a2e:0370:7334—offering more flexibility.
Packet Header Format: Changes to the packet headers in IPv6, including removal of checksum and fragmentation fields, aim to streamline processing and efficiently route packets end-to-end.
Capabilities: IPv6 includes additional features over IPv4 like stateless address auto-configuration to assign IP addresses without a server and native IPsec security.
Adoption: IPv6 deployment is still gradually expanding across the internet—for example, Google reports approximately 40% of visitors to its sites use IPv6. Coexistence and interoperability mechanisms allow IPv4 and IPv6 hosts to communicate during this transitional period.
The switchover to IPv6 aims to future-proof internet addressing as networks continue expanding exponentially. While IPv4 is still ubiquitous, support and adoption of its successor steadily grows to handle tomorrow’s addressing needs.
Main Types of IP Addresses Explained
In networking, computers, servers, printers, IoT devices, and other endpoints connect via IP addresses. There are a few common flavors of these essential endpoint identifiers:
Public IP Address: Devices utilize these globally routable addresses to directly communicate with other public hosts on the internet. ISPs generally assign public IPs dynamically.
Private IP Address: Local networks assign these addresses from designated internal ranges to only enable communication between their private hosts, not directly over the public internet. Home routers often handle dynamic private IP assignment.
Shared IP Address: This entails multiple hosts sharing a single public IP to connect through some intermediary network hardware, typically a router or proxy server. Public Wi-Fi hotspots usually rely on shared IP addressing.
Dedicated IP Address: As the name suggests, dedicated IP addressing assigns a static public IP exclusively to one user, server, or device without any sharing across multiple endpoints.
These different varieties of IP addresses coordinate to facilitate public and private communication involving internet-enabled systems.
How Do Transport Protocols Like TCP Make the Internet Work?
While IP handles core addressing and routing functions, TCP and other transport protocols pick up the data at either end and ensure proper transmission. This process includes:
Sequencing: TCP assigns a sequence number to each transmitted byte to reassemble packets in the correct order.
Error checking: A checksum verifies the integrity of received data against corruption. The recipient can request retransmission if errors are detected.
Acknowledgments and flow control: TCP maintains a running tally of successfully received packets and adjusts the sender’s rate to prevent overwhelming the recipient’s buffers.
Connections: TCP establishes logical connections to deliver data streams reliably between applications.
Congestion avoidance: By dynamically monitoring dropped packets and adjusting transmitter window sizes, TCP aims to throttle traffic before congestion necessitates retransmissions.
Thanks to these key mechanisms for handling error-checked, sequenced, reliable data transport between networked applications, TCP serves as the workhorse transport protocol powering HTTP web traffic, SMTP email transfers, SSH remote connections, and more. Alternatives like UDP offer less overhead for non-critical workloads.
In Conclusion: Internet Protocols Form the Foundation
I hope this high-level overview clearly explains what internet protocols are and how they enable our connected world. Although the technical details can get complex, the essential foundations of internet protocols are straightforward—they provide common languages and structures so diverse networks, devices, and operating systems can interoperate smoothly. Thanks to agreed-upon standards for addressing, sequencing, error checking, flow control and more, we can exchange vast amounts of data seamlessly over the global internet.
Frequently Asked Questions
What is the difference between an internet protocol and a transport protocol?
Internet protocols like IP handle core functions like addressing and packet routing, while transport protocols like TCP focus on end-to-end transmission details such as flow control, sequencing, and error correction. Together, they form complete, robust standardized protocols for communication.
Why do we need to transition from IPv4 to IPv6?
The primary driver for adopting IPv6 stems from IPv4’s limited pool of around 4 billion addresses. Rapid expansion of the internet of things (IoT), smart devices, high-speed wireless networks and more across both developed and emerging markets created demand for more addresses. IPv6 massively expands the available space for reliable IP addressing moving forward.
What does an internet protocol do?
An internet protocol sets common rules to allow diverse networks and devices to communicate effectively. Key functions include breaking data into individually routed and sequenced packets, handling addressing and metadata in packet headers, and facilitating data transfer handling like error checking between endpoints. Adhering to these common internet protocols enables unified communication systems.
