How data travels across a network

Every day, we send emails, stream movies or join video calls without giving much thought to what happens when we hit "send" or press play. But behind the scenes, a complex process is at work to make sure the right data reaches its destination quickly and reliably.

Understanding how a network works isn't just tech trivia. It can help explain why your Zoom call lags, why a large file takes forever to download or why your Wi-Fi® feels slow.

Below, we'll break down how data travels across a network, addressing common questions like "What is a packet in networking?" and "How does wireless internet work?" By the end, you'll have a clear picture of the process that powers the internet and a better understanding of what happens every time you go online.

Networking terms to know

Before diving into how data travels, let's define a few key terms.

When we talk about a network, we're referring to a system of connected devices-computers, servers, routers, switches and so on-that communicate and send data to each other. Networks can be as small as a home Wi-Fi setup or as vast as the internet, which itself is a global network of millions of smaller networks working together.

When data moves across a network, it's broken down into small, manageable pieces called packets. Each packet carries a portion of the information, plus details about where it's headed.

These packets move according to network protocols, or the rules that define how data is formatted, transmitted and received. To understand and standardize how these protocols work, two fundamental frameworks are commonly referenced: the OSI model and the TCP/IP model.

Both models organize network protocols into layers, essentially breaking a complex process into clear steps and rules that everyone can follow. This layered approach makes networks easier to design and manage. It also simplifies troubleshooting since problems can usually be traced back to a specific layer.

The TCP/IP model keeps things simple with four layers. It's practical, scalable, and the foundation of the modern internet. The OSI model expands the idea into seven OSI layers and serves mainly as a reference model for understanding and teaching networking concepts. Together, they provide a structured way to think about how data flows across networks.

How does network data travel?

Now that we've covered the basics, let's follow a piece of data as it travels across a network.

Step 1: Data origination

Every journey starts with a source. Let's say you're making a Voice over Internet Protocol (VoIP) phone call, which is a type of telephony that works over the internet. The source would be your voice, which the VoIP device converts from analog audio waves into digital data. This conversion ensures the data can be read and transmitted by network devices.

Step 2: Data packetization

Next, the data is broken into packets. Each packet carries part of your message along with important details, like the sender's and receiver's IP addresses and instructions for how everything should be reassembled once it reaches its final stop.

This process is all about making transmission faster and more efficient. Think of it like sending a puzzle one piece at a time, each with a mini-guide for where it fits. It's faster and easier than trying to ship the whole puzzle in one clunky package.

Step 3: Transmission across the network

Once the data is packetized, it's ready to move. Data packets can travel over copper wires, through fiber-optic cables or even through the air if you're using wireless internet.

On Wi-Fi, your device sends packets over invisible radio-like waves to your router. From there, they hop onto cables that link your home network to your internet service provider and eventually across the wider internet.

Along the way, packets encounter two key devices: routers and switches.

What's the difference between routing vs. switching? Routers work between networks, reading each packet's destination and choosing the best path forward. Switches operate inside a network, directing packets between devices like your laptop and printer.

So in a VoIP call, for instance, your router decides the fastest route for your voice packets to reach the recipient outside of your network, while a switch makes sure those packets move efficiently between devices in a home or office.

Packets don't have to stick together. If one path is slow or blocked, they automatically take an alternate route. This adaptability allows for fast and reliable transmission, but because packets may arrive at slightly different times, it can also cause network jitter. In real-time communications, jitter can result in choppy audio, lagging video or even dropped calls.

Step 4: Protocol handling and delivery

Finally, the packets reach their destination. The receiving device checks each packet, puts them in the correct order and converts the digital data back into something meaningful, like your voice call, an email or a video.

If any packets are missing or arrive corrupted, error-checking protocols step in. The device quickly requests a resend of the missing pieces, ensuring nothing is lost. All of this happens in milliseconds, so the process feels instant and seamless. Your call sounds clear, your video plays smoothly and your messages appear without delay.

Understanding network performance

So, why does all this matter? Because the way network data travels directly affects your online experience, whether that means a crystal-clear VoIP call or a buffering video stream.

Think of your internet connection like a pipe. Bandwidth is the width of the pipe-how much data can flow through at once-while internet speed is how quickly that data moves through the pipe. When everything works as it should, packets travel smoothly and arrive at consistent intervals. But several issues can occur:

• Network congestion. When too many devices are using the same network, the pipe gets congested. Data packets are forced to wait their turn, causing lag or buffering. Upgrading bandwidth or using Quality of Service (QoS) settings to prioritize certain traffic can help.
• Poor hardware. An outdated router or switch can act like a narrow pipe, unable to handle the data load efficiently.
• Lack of packet prioritization. Time-sensitive data-like voice or video from a VoIP call-needs to move faster than a file download. Without prioritization, these packets arrive late, creating choppy audio or frozen screens. QoS settings and elements like a session border controller (SBC) can help manage VoIP traffic and ensure smooth communication.
• Packet loss. Sometimes packets get lost en route. Devices have to request a resend, creating delays as packets arrive unevenly. IT teams can perform a network packet capture to intercept and log data packets for analysis, troubleshooting or monitoring.
• Wireless issues. Wi-Fi signals can be disrupted by walls, distance or other devices, leading to slow speeds and dropped connections. Positioning routers strategically or using wired connections for high-demand tasks can improve reliability.

By understanding these performance factors, you can see why network design matters. After all, your online experience depends on data moving through the digital "pipes" as efficiently as possible.

Your data's journey

Every click, call and stream sets off a journey. Understanding how data travels through networks shows why a solid network really makes a difference. Next time your VoIP call goes smoothly or your video streams without buffering, you'll know a little bit about all the tiny packets making it happen behind the scenes.

If you'd like those smooth calls to include your customers, helping make your business more efficient while being affordable, Ooma Office can help. Find out how here.