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I always have a window open running a continuous with ping -t 8.8.8.8.

Many times my TTL changes after awhile and it causes disconnecting and reconnecting of apps and games. For example my TTL is 117 for one hour and without explanation it changes to 121. When it changes my apps and games disconnect and reconnect automatically.

This is so annoying and none of the support technicians can explain what's going on.

As long as I'm not a autonomous, can anyone explain to me what's going on with these TTL changes?!

I have Windows 10.

I say Reinstate Monica
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Alireza Mohebi
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  • Does your (public) IP change as well? – Kamil Maciorowski Nov 03 '18 at 08:50
  • @twisty-impersonator, it looks like you created the [ttl] tag and wiki excerpt. Two questions: 1. Any chance that the tag will get misused and applied to other TTL meanings (if it's needed, would it be better spelled out rather than an acronym)? 2. The excerpt doesn't track with the Wikipedia definition: a mechanism that limits the lifespan of data in a computer or network (I'm not a networks guy so it's out of my area, but wanted to raise the question). – fixer1234 Nov 03 '18 at 21:29
  • @fixer1234 good point on possible name collision given the short acronym. I'll see about "renaming" it because, while I can't think of another identical term, it seems likely one could exist. I'll tweak the except too. Excellent feedback--thanks! – I say Reinstate Monica Nov 03 '18 at 21:32
  • @TwistyImpersonator, when I first saw it, I thought it was referring to transistor–transistor logic used in ICs. :-) – fixer1234 Nov 03 '18 at 21:37
  • @fixer1234 LOL, no kidding! OK, I obviously gotta fix that. – I say Reinstate Monica Nov 03 '18 at 21:43

1 Answers1

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Communication over the Internet is accomplished by sending many small packets of information. Each packet is moved from its source to destination by devices called routers. Routers connect the many different smaller networks that comprise the public Internet.

When a packet goes through a router, the router decrements the packet's TTL (Time To Live) field. This is done for two purposes:

  • It provides a mechanism to know how many routers (i.e. hops) the packet has traversed

  • It prevents packets from being transmitted in an infinite loop in the event of a network configuration error. When the TTL reaches zero routers will discard the packet.

The 'ping' command shows you the received TTL after it has already gone through this dec­re­menting. Usually the sender specifies a TTL of 128 (or 64), so if you receive it with TTL 117, that means it has travelled through 11 routers (128-117).

Can anyone explain me what's going on with TTL changes?!

Routers on the Internet usually have multiple connections to other routers. Often the routers will have multiple connections that could be used to deliver your packet. The routers job is to pick the best one. Because of changing network conditions a router may not always pick the same route each time for your packets. When this happens, your packet may end up traversing a path that involves a different number of routers. This is why you see a different TTL. This is perfectly normal. The fact there are multiple routes between destinations is indeed one reason the Internet is so resilient.

my TTL is 117 for 1 hour and just in a moment with no clue it changes to 121 and with this change my apps and games has disconnect and reconnect

In this case your TTL changing is not the cause of your problem but rather a symptom. Whatever is causing your temporarily loss of Internet connectivity is also resulting in your packets taking a different route to their destination. If the TTL is changing for all of your packets, that suggests the problem is very close to you, either in your own LAN or in your ISP's network.

u1686_grawity
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I say Reinstate Monica
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    Picking a different path is especially common for 8.8.8.8 and similar [anycast](https://en.wikipedia.org/wiki/Anycast) servers, because it can also mean getting rerouted to a different instance while the original one is under maintenance or such. – u1686_grawity Nov 03 '18 at 13:45
  • thanks a lot mate , I almost understood your explanation with a bit more study and search . – Alireza Mohebi Nov 04 '18 at 09:21
  • @AlirezaMohebi you're welcome. If this answered your question please tick the green checkmark to indicate that. – I say Reinstate Monica Nov 04 '18 at 11:47