What is Traceroute ? How does it Work ? How To Run a Traceroute ?

Traceroute is a network diagnostic tool used to track the route that data packets take from your computer to a destination host, such as a website or server.

It helps identify the path and measure the time it takes for data to travel between your computer and the destination.

Traceroute is commonly used to troubleshoot network issues and understand the network topology.

Here's how traceroute works:

1. Packet Routing: Traceroute sends a series of packets towards the destination, with each packet having an incrementally increasing Time-to-Live (TTL) value.

2. ICMP Messages: When a packet's TTL reaches zero, the router or network device discards the packet and sends an ICMP Time Exceeded message back to the source.

3. Recording Hops: Traceroute records the IP addresses or domain names of the routers or devices that responded to the ICMP Time Exceeded messages. It also measures the round-trip time for each hop, indicating the time it took for the packet to travel from the source to that specific router and back.

4. Repetition: Traceroute repeats this process multiple times, usually sending three packets for each TTL value. This helps provide a more accurate picture of the route and allows for variations in network conditions.

5. Endpoint Reached: When the packets finally reach the destination, the destination responds with an ICMP Echo Reply, indicating that the target has been reached. Traceroute then stops its operation.

What is Traceroute Used For?

Traceroute is a network diagnostic tool used to track the pathway taken by a packet on an IP network from source to destination.

It provides valuable insights into the route packets take and measures transit delays across routers locally or globally.

Traceroute is primarily used for diagnostic purposes, allowing system administrators and network engineers to visualize traffic flow within an organization, identify irregular paths, and troubleshoot connectivity issues.

How To Run a Traceroute, Explained :

Windows:

1. Open a command-line prompt.

2. Use the "tracert" command followed by the hostname or IP address you want to trace.

Linux:

1. Open your Terminal Emulator.

2. Type "traceroute" followed by the hostname or IP address you wish to trace.

Mac:

1. Open the "Terminal" App.

2. Type "traceroute" followed by the hostname or IP address you want to trace.

Running a traceroute helps diagnose network issues and provides valuable information about the path that data takes from your computer to a destination.

Some common errors that can occur when running a traceroute :-

1. Request Timed Out: This error typically represents a network issue and can occur due to problems on the return path or the destination's security device blocking the request.

2. Asterisk Symbols Under RTT Columns: Asterisks indicate that the device failed to respond to the request before the specified time.

3. Destination Net Unreachable: This error informs you that IP packets failed to find a route to the destination address, often due to issues with routers or non-existent destination IP addresses

These errors can help identify connectivity problems, routing issues, or network failures at specific hops along the traceroute path.