# Pinging **URL:** \ **Category:** Factual Questions\ **Created:** [December 7, 2000, 1:47pm UTC](https://boards.straightdope.com/t/pinging/44470 "2000-12-07T13:47:58Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Oblong](https://avatars.discourse-cdn.com/v4/letter/o/c0e974/32.png) [@Oblong](https://boards.straightdope.com/u/Oblong)\ **Post date:** [December 7, 2000, 1:47pm UTC](https://boards.straightdope.com/t/pinging/44470/1 "2000-12-07T13:47:58Z")
When pinging another computer on your network, what does the TTL mean? Is that a measure of time? What is an acceptable TTL if that is time? We have an Ethernet with about 10 computers in one office. ---
**Author:** ![dylan\_73](https://avatars.discourse-cdn.com/v4/letter/d/ecccb3/32.png) [@dylan\_73](https://boards.straightdope.com/u/dylan_73)\ **Post date:** [December 7, 2000, 1:57pm UTC](https://boards.straightdope.com/t/pinging/44470/2 "2000-12-07T13:57:17Z")
This is the Time To Live. Each time a packet goes through a router, this number is decreased by one. When it reaches zero the packet is dropped. This basically makes sure that if the packet gets lost it doesn’t hang around the network forever. In most packets the TTL is set to 60, but it’s set to 255 for ping. From the TTL you can get an indication of how many routers the packet has passed through. Also, if different packets have different TTLs, it means that the packet is taking different routes through the network. This may be a bad thing, and can indicate a faulty configuration. If you need more info, searching on the web for ‘ping’ (and possibly ‘traceroute’) should give more details. ---
**Author:** ![Spiny\_Norman](https://avatars.discourse-cdn.com/v4/letter/s/9de0a6/32.png) [@Spiny\_Norman](https://boards.straightdope.com/u/Spiny_Norman)\ **Post date:** [December 7, 2000, 7:48pm UTC](https://boards.straightdope.com/t/pinging/44470/3 "2000-12-07T19:48:36Z")
Heh - the old CCIE Drake test had the question: “What is the purpose of the TTL field ?” and one of the answers were “To make us ponder the brevity of life”… dylan nailed it. I belive it was introduced specifically to prevent routing loops, which are (rightly) considered a Bad Thing. S. Norman ---
**Author:** ![City\_Gent](https://avatars.discourse-cdn.com/v4/letter/c/a87d85/32.png) [@City\_Gent](https://boards.straightdope.com/u/City_Gent)\ **Post date:** [December 7, 2000, 9:30pm UTC](https://boards.straightdope.com/t/pinging/44470/4 "2000-12-07T21:30:44Z")
A side note: The guy who wrote the original ping program died within the last couple of weeks. I looked for a link but couldn’t find one. ---
**Author:** ![manhattan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manhattan/32/7_2.png) [@manhattan](https://boards.straightdope.com/u/manhattan)\ **Post date:** [December 7, 2000, 11:07pm UTC](https://boards.straightdope.com/t/pinging/44470/5 "2000-12-07T23:07:22Z")
Guess the poor guy should have set his TTL a little higher… ---
**Author:** ![rowrrbazzle](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rowrrbazzle/32/414_2.png) [@rowrrbazzle](https://boards.straightdope.com/u/rowrrbazzle)\ **Post date:** [December 8, 2000, 12:11am UTC](https://boards.straightdope.com/t/pinging/44470/6 "2000-12-08T00:11:50Z")
> **[RIP Mike Muuss, PING author](https://www.theregister.com/2000/11/22/ping_author_killed_in_car/)** > > Killed in car crash which I got from here: > **[The Author of Ping is Reported Dead - Slashdot](https://news.slashdot.org/story/00/11/23/1616201/the-author-of-ping-is-reported-dead)** > > Wedman writes: "This is in the Nanog Archive, dated 2000-11-21: > 'Mike Muuss, the author of the PING program used on networks everywhere, died last night in a traffic accident on US route 95 in Maryland. He was an alumnus of Johns Hopkins." Seems... ---
**Author:** ![Manduck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manduck/32/256_2.png) [@Manduck](https://boards.straightdope.com/u/Manduck)\ **Post date:** [December 8, 2000, 1:01am UTC](https://boards.straightdope.com/t/pinging/44470/7 "2000-12-08T01:01:51Z")
> [@](#): > > \*Originally posted by City Gent \* > \*\*A side note: The guy who wrote the original ping program died within the last couple of weeks. \*I looked for a link but couldn’t find one. \*\*\* Let’s all ponder the irony of this for a moment