What it means
Tools send probes with progressively increasing hop limits. Routers may return expiry messages, allowing their addresses and probe round-trip times to appear. Paths can differ by direction or change during the test. Some routers filter or deprioritise diagnostic replies while forwarding normal traffic correctly.
How this affects everyday use
Firewalls, rate limits and alternate paths can create asterisks or inconsistent results. A delay visible at one hop but absent later may describe that router's reply handling rather than ongoing traffic delay.
A practical example
One line shows no replies, yet later routers and the destination respond normally.
What to check
- Repeat toward the same affected destination.
- Compare final delivery and application behaviour, not only intermediate lines.
- Record times and whether tests were wired or wireless.
Practical next steps
- Use the result with ping, loss and service evidence.
- Investigate local faults if delay starts before the gateway.
- Provide sanitised repeated traces to authorised support when useful.
Keeping it reliable
Do not publish internal addresses or sensitive network details indiscriminately. Avoid declaring ownership or fault from a hostname alone. Traceroute shows observations, not a complete map or guaranteed root cause.