8 ms·
Forwarding packets happens in ASICs, generating ICMPs is usually done by the CPU (which has a packet rate of maybe 1/100000th of the ASICs). So the latter is us
by Sesse__ 6y ago
Forwarding packets happens in ASICs, generating ICMPs is usually done by the CPU (which has a packet rate of maybe 1/100000th of the ASICs). So the latter is usually either rate-limited or turned off entirely, or you could bring the router to its knees by just spamming packets with too short TTL. It's also not uncommon that people turn it off to reduce external insight into their network, for whatever reason.
- usr1106 6y agoRight, but the weird thing was that grand parent got a full trace up to the target and I didn't as usual. By experimenting a bit I found that when sending UDP packets the traceroute is incomplete, but when sending ICMP also my traceroute is complete. Explains how the grandparent could present a full traceroute. I had just taken it as a fact that full traceroutes are rarely possible these days. For reasons like you say, it's overhead for them and they don't want you to do it.