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A comment on Show HN: How did your computer reach my server?. Parent comment

Re:Show HN: How did your computer reach my server? by emmelaich on Tuesday December 05, 2023 @07:49PM (#38539083)
Is that still true? https://www.rfc-editor.org/rfc/rfc3443.txt has no mention of seconds.

It just says that outputTTL is (inputTTL - 1). With some exceptions.

[edit: I missed that that RFC is for MPLS but would be interested in your comment anyway; the definitive version seems to be https://datatracker.ietf.org/doc/html/rfc1122]

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Re:Show HN: How did your computer reach my server? by js2 on Wednesday December 06, 2023 @09:58AM (#38544662)
RFC 791:

> The time is measured in units of seconds, but since every module that processes a datagram must decrease the TTL by at least one even if it process the datagram in less than a second, the TTL must be thought of only as an upper bound on the time a datagram may exist.

https://www.rfc-editor.org/rfc/rfc791.html

The equivalent field in IPv6 is named hop limit in recognition of how the TTL field is used in practice with IPv4:

https://www.rfc-editor.org/rfc/rfc2460.html

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