Is traceroute an ICMP component?

[Mitrixsen]

Hello, everyone.

I am studying ICMP for my ENCOR exam and I have a question about traceroute.

When it comes to ICMP, there are several components/utilities such as ping that can be used for network diagnosis. For example, a simple ping consists of an ICMP Echo Request message that is sent to the destination and an ICMP Echo Reply that is sent to respond to the requests to verify basic connectivity .

How is it with traceroute, though? Traceroute isn't on its own an ICMP message but it does rely on the ICMP TTL Exceeded message in order to perform its operation, correct?

So how is it with traceroute? Is traceroute a part of ICMP/is it an ICMP component or is it separate from it?

Thank you.

David

[M02@rt37 · Accepted solution]

Hello David

Hope you exam prep is running perfectly! Traceroute is not an ICMP message or protocol itself, but it relies on ICMP messages to function. We are agree that it's diagnostic utility used to map the path packets take throught a network by leveraging TTL-based expiration and ICMP responses.

The way traceroute works is by sending packets with incrementally increasing TTL values. Each router along the path decrements the TTL, and when it reaches zero, the router discards the packet and responds with an ICMP Time Exceeded message. Traceroute records these responses to identify the routers along the path...

On the final hop, the behavior depends on the protocol used. In Windows, traceroute uses ICMP Echo Requests, and the destination responds with an ICMP Echo Reply. On Linux, macOS, and Cisco devices, traceroute typically uses UDP packets to high-numbered ports, and when the destination is reached, it responds with an ICMP port unrachable message since no application is listening on that port.

While traceroute itself is not part of ICMP ? It relies on ICMP messages—specifically ICMP Time Exceeded and ICMP Destination Unreachable—to complete its function. Therefore, it is best understood as a tool that makes use of ICMP rather than being a native component of it.

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https://serverfault.com/questions/374620/does-traceroute-use-udp-or-icmp-or-both

[Joseph W. Doherty]

I agree with M02@rt37 , further, and likewise, ping should be considered the same, i.e. it's not an ICMP component, but makes use of ICMP.

Consider any app could also "ping".  Or consider, any app using UDP or TCP, are not components of either.

So, your thinking ping is a component of ICMP, is leading to confusion of what traceroute also is.