What is traceroute: What does it do and how it works? 

Key takeaways:

• Learning how to use traceroute to diagnose network issues 
• Traceroute helps identify network issues 
• Understanding when to use traceroute versus ping for network troubleshooting  

Have you ever had a website load painfully slow or noticed your internet dragging? Traceroute can help. Think of it like a GPS for your internet—it maps your data’s exact route, helping you pinpoint delays or connection problems.  

Every second, trillions of data packets move through fiber-optic cables and undersea wires to keep the world connected. Traceroute helps track where the issue is happening when things slow down, allowing you to troubleshoot effectively with the traceroute command. 

This guide covers what is traceroute, how it works, and how to use it to diagnose network issues. 

What is a traceroute? 

Traceroute, or the ‘tracert’ command on Windows, is a tool that shows the path your data takes to reach a website or server. The ‘tracert’ command is the Windows version of the traceroute tool, which works the same way on Mac and Linux as ‘traceroute’. In addition to that, traceroute lists each “stop” (a router or server) along the way and how long it took to get there. 

The traceroute output provides valuable insights. It shows the TTL exceeded message when a packet doesn’t reach its destination within the time limit, highlighting network issues or misconfigurations. 

This helps you:  

• Find network problems. See if your data is taking a weird, roundabout route. 
• Diagnose reasons for slow internet. Figure out where slowdown is happening. 
• Spot lost data. See if any data gets lost along the way. 

Knowing how traceroute sends packets and interprets the traceroute output can make it easier to do effective network troubleshooting. Thus, improve your internet connection. 

What is tracert? 

Tracert is the Windows-specific version of traceroute. It works the same way but is used in the Windows command prompt. It shows the path your data takes through different routers and servers. The tracert command helps you find where delays or network bottlenecks are happening. 

What is tracert command? 

The tracert command in Windows tracks your data’s journey through the internet. It lists each router or server your data passes through. It also shows how long it takes to reach each one. Using the tracert command helps you find slowdowns or network issues so you can troubleshoot them faster. 

Key terms to know

• Hops. The stops your data makes along its journey. Each hop represents a router or server that processes and forwards your data. 
• Latency. The time it takes for data to travel from one hop to the next. High latency can lead to slow speeds and lag. 
• TTL (Time-to-live). A counter that limits how long a packet can travel before being discarded to prevent endless loops. 
• ICMP messages. Traceroute uses these messages to gather information about each hop and measure response times. 

If a specific hop takes too long or fails to respond, that’s usually (but not always) where the issue lies. By following the data’s path, traceroute gives you a behind-the-scenes look at your internet connection, helping you troubleshoot like a pro. 

How does traceroute work? 

Traceroute works by sending small packets of data, like ICMP packets (Internet Control Message Protocol), to a destination. It measures the time it takes for each hop along the way. This is where the traceroute command comes in—it’s the tool you use to run a traceroute and visualize these steps in action. 

Here’s how it works: 

1. Sending data. Your computer sends a small packet with a limit on how many stops it can make before being discarded. Tracert helps track this path by controlling the limit. It shows you the route using the internet protocol and reveals the journey your data takes from start to finish. 
2. Tracking hops. Each router reduces the limit and sends a response back. It also reveals the IP address of each hop along the way. 
3. Identifying delays. Tracert records how long each stop takes. This helps you find where delays or problems happen. The delays could be caused by issues with UDP packets (User Datagram Protocol) or other types of data transmission. 

Traceroute vs. Ping 

While traceroute and ping help diagnose network issues, they serve different purposes.  

Ping checks whether a device is reachable by sending a single packet and waiting for a reply. It usually tells you if the destination is online but doesn’t show the path the data takes or where delays occur. 

Traceroute, on the other hand, provides a detailed map of your data’s path. It shows each hop, the IP address at each router, and how long it took to get there. It’s the better tool for identifying where slowdowns are happening in a network. Traceroute uses ICMP packets to troubleshoot routing and internet protocol issues. 

How to run a traceroute command 

Let’s break down how to use the traceroute command. It’s a handy tool for seeing the path your network traffic takes to reach a specific destination. Think of it like following the breadcrumbs of your connection. 

For Windows users: 

Step 1. To do this, open your command prompt. The command prompt opening method varies slightly depending on your Windows version. 

1. Older Windows (like XP). Click Start, then Run, type cmd, and hit OK. 
2. Newer Windows. Type cmd into the Start menu search bar. 

Step 2. A black window with white text (that’s the Command Prompt) will be open. It’s waiting for your instructions. Type the following, replacing google.com with whatever website you want to trace: 

Step 3. Seeing the results. Press the Enter key. Your computer will now send unique signals to trace the route to Google.com. You’ll see a list of “hops” — each hop is a server or router that your connection passes through. It might look something like this (but the exact details will be different for you): 

In Windows, the tracert command is a built-in version of traceroute. It’s an easy-to-use tool that helps diagnose network problems by revealing your data’s exact route. 

For Mac users: 

Step 1. Open Terminal. This is the Mac equivalent of the Windows Command Prompt. It’s where we type commands. Here’s how to find it: 

1. Using Finder:  

• Open a new Finder window (you can do this by clicking on the Finder icon in your Dock or by pressing Command + N). 

• In the Finder sidebar, click on “Applications”. 

• Find the “Utilities” folder in the Applications folder and open it.   

• Inside the Utilities folder, you’ll find the “Terminal” app. Double-click it to open it. 

Step 2. A window called “Terminal” will pop up. Type the following, replacing google.com with the website you want to trace: 

Step 3. Seeing the results. Press the Return key (it’s like the Enter key on Windows). Your Mac will start the traceroute. You’ll see a list of hops, similar to what we saw on Windows. It might look something like this (but again, the details will be different for you): 

Key points for Mac: 

• The command is traceroute (no “tracert” like in Windows). 
• You use the Return key, not Enter. 

So, the traceroute shows you each stop your connection makes and how long it takes to get there. It’s a useful way to see if there’s a slow connection somewhere along the route. 

For Linux/Unix users: 

Step 1. In Linux/Unix, the command-line interface is called a “terminal” or “console.” How you open it depends a bit on your specific Linux distribution (like Ubuntu, Fedora, etc.) or Unix system. Here are the most common ways: 

• Menu: Many desktop environments have a menu option for “Terminal,” “Console,” or “xterm.” Look in your applications menu, often under “Accessories,” “System Tools,” or “Utilities.” 
• Keyboard Shortcut: Often, Ctrl+Alt+T will open a terminal. Try this first! 
• Search: Use your desktop’s search function and type “terminal” or “console.” 

Step 2. Once the terminal window opens, you’ll see a prompt (something like user@yourcomputer:~$). Type the following command, replacing google.com with the target IP address or website you want to trace: 

Step 3. Testing network performance. Press Enter. Linux/Unix will start the traceroute tool. The results will appear in the terminal window, showing each hop along the network path, the time it takes, and the icmp traffic along the way. 

The results will look similar to the Mac output.

You can quickly determine where issues along the network path may be causing slow connections or dropped packets. 

Here are a few extra tips:   

• Redirection across platforms. The redirection operators (> and >>) work consistently across Windows, Mac, and Linux/Unix. 
• Stopping the traceroute. If you need to stop it midway, press Ctrl+C. This works the same way on Windows, Mac, and Linux/Unix.   
• Saving the results (all OS). Want to keep a record? You can save the traceroute output to a file. 
• To create a new file. Add > filename.txt to the end of your command. For example: tracert www.example.com > tracert.txt 
• To add to an existing file. Use >> filename.txt instead. For example, tracert www.example.com >> tracert.txt is useful if you’re running multiple traceroutes and want to compile the results in one place. The files will be saved to your primary hard drive. 

How to read traceroute results 

When you run a traceroute, the traceroute output lists multiple hops, each representing a stop along your data’s journey. Understanding these results helps you pinpoint network slowdowns and connectivity issues. 

Key columns in the output 

• Hop number. The sequence of stops your data makes along the route. 
• Response times (ms). The time it takes for data to reach each hop. Lower numbers indicate faster speeds, while high numbers suggest delays. 
• IP address/hostname. The intermediate routers or servers your data passed through. Some may display hostnames, while others only show IP addresses. 

What the results indicate 

• Low response times. A standard, fast connection with no significant delays. 
• Sudden spikes in latency. Possible network congestion or an overloaded server may cause intermittent slowdowns.   
• Consistently high response times. A sign of ongoing network delays that could indicate a routing issue or an underperforming internet service provider (ISP). 
• Timeouts (“Request Timed Out”). A firewall, network block or a non-responding server may be preventing data from passing through. The destination host’s unreachable message could also appear in this scenario, signaling a failure to reach the intended server.   

If the ICMP TTL exceeded message appears, the network routes are being tested but couldn’t be fully completed due to issues. By analyzing the traceroute output, you can determine where slowdowns occur and troubleshoot accordingly. The problem could be within your local network, at your ISP, or further along the route to the destination host unreachable. 

Quick fixes for common network issues 

Instead of spending time troubleshooting network issues without a clear answer, here’s how you can quickly use traceroute to find and fix common network problems: 

• A sudden spike in latency. Restart your router or contact your ISP. 
• Time-outs in the middle of the route. Could be a firewall issue. Try disabling VPNs or adjusting network settings. 
• A long delay before the first hop. It’s likely a local network issue. Restart your modem or move closer to your Wi-Fi source.   

With traceroute, it’s all about finding the trouble spots and taking action to get your connection back on track. When you run the traceroute command, it reveals each hop and the IP address of the routers along the way, helping you understand where delays occur. 

Trace the best path to a faster website 

You now recognize the function of traceroute in assessing network efficiency, troubleshooting connection problems, and pinpointing sluggish routing paths. With this knowledge, you can take steps to ensure a smooth, effective website. 

Ensuring secure connections is crucial. If traceroute indicates issues with data transmission or timeouts, the TTL exceeded message might appear, signaling a potential bottleneck. SSL certificates from Domain.com can help by securing your connections, enhancing performance and security, and ensuring uninterrupted access to your website. 

Frequently asked questions (FAQs)