# When Traceroutes Lie: How TTL Jumps Can Give Us a False Impression of the Internet's Topology

DevFeed: [When Traceroutes Lie: How TTL Jumps Can Give Us a False Impression of the Internet's Topology](<https://devfeed.tech/articles/when-traceroutes-lie-how-ttl-jumps-can-give-us-a-false-impression-of-the-internet-s-topology-11453.md>)

Original publisher: [Read original article](<https://labs.ripe.net/author/shk/when-traceroutes-lie-how-ttl-jumps-can-give-us-a-false-impression-of-the-internets-topology/>)

Author: Sebastian Kappes

Published: 2026-09-03T12:03:26Z

Content type: article

Language: en

Sources: [RIPE Labs](<https://devfeed.tech/sources/ripe-labs.md>)

Topics: [Internet](<https://devfeed.tech/topics/internet.md>), [Networks](<https://devfeed.tech/topics/networks.md>), [debugging](<https://devfeed.tech/topics/debugging.md>)

Tags: [atlas](<https://devfeed.tech/tags/atlas.md>), [competition](<https://devfeed.tech/tags/competition.md>), [debugging](<https://devfeed.tech/tags/debugging.md>), [internet](<https://devfeed.tech/tags/internet.md>), [measurements](<https://devfeed.tech/tags/measurements.md>), [networks](<https://devfeed.tech/tags/networks.md>), [research](<https://devfeed.tech/tags/research.md>), [router](<https://devfeed.tech/tags/router.md>)

## AI overview

This article explains how routers that rewrite or fail to decrement TTL values can cause traceroute to omit entire networks and create a false impression of Internet topology. It describes the normal traceroute mechanism and measurements using RIPE Atlas probes to investigate the behavior.

## Source excerpt

Traceroute is a powerful tool for uncovering how packets travel across the Internet. However, as we recently discovered, some routers tamper with the TTL values in traceroute's probing packets, giving you a false view of how networks are actually interconnected.