Thanks for engaging with this. I was intentionally brief in my explanation. I have observed this behavior in congested networks for years and ignored it as an obvious symptom of the congestion. What has always piqued my curiosity though is just how long a ping can last. In my case yesterday, I was at the airport at peak holiday travel and free wifi usage time. I expect a bad experience. I don't expect a ping to return 5 seconds after originating it. I just imagine the network straining and groaning to get my ping back to me. It's okay, man. Let it go. On Thu, Dec 22, 2022 at 5:22 AM Masataka Ohta < mohta@necom830.hpcl.titech.ac.jp> wrote:
Jerry Cloe wrote:
Because there is no standard for discarding "old" traffic, only discard is for packets that hop too many times. There is, however, a standard for decrementing TTL by 1 if a packet sits on a device for more than 1000ms, and of course we all know what happens when TTL hits zero. Based on that, your packet could have floated around for another 53 seconds.
Totally wrong as the standard says TTL MUST be decremented at least by one on every hop and TTL MAY NOT be decremented further as is specified by the standard of IPv4 router requirements (rfc1812):
When a router forwards a packet, it MUST reduce the TTL by at least one. If it holds a packet for more than one second, it MAY decrement the TTL by one for each second.
As for IPv6,
Unlike IPv4, IPv6 nodes are not required to enforce maximum packet lifetime. That is the reason the IPv4 "Time to Live" field was renamed "Hop Limit" in IPv6. In practice, very few, if any, IPv4 implementations conform to the requirement that they limit packet lifetime, so this is not a change in practice.
Masataka Ohta