Need help figuring out why I am having connection issues (~10 second lag spikes every couple minutes)

What level of latency spikes are you seeing? Is this to specific sites or everywhere?

Since they come and go so quickly it's going to be hard to get a handle on it.  You'd probably want to run a traceroute to something like google.com when things are normal and then when they're spiking and post the results here.

As you surmised, this is going to be really difficult for a tech to figure out because it's not likely to happen when one of them is around.

You mentioned AT&T has run fiber in the neighborhood.  I take it that for some reason your house isn't eligible for fiber?

We're happy to help with your connection issues, @TTrain750.

Thank you @tonydi for the information and questions.

We have more information on understanding high latency & ping. It explains what is acceptable latency and understanding traceroute and ping.

As @tonydi mentioned, please let us know:

1. What level of latency spikes are you seeing? (Share pictures or results so we see what is going on).
2. Is this to specific sites or on every site?

We will be looking forward to your response.

Elmi, AT&T Community SPecialist.

The lag spikes have not occurred since two nights ago when I posted this but I am not convinced they won't pop up again.  The last time this happened it occurred on and off for over a month until it was properly resolved.

I've run trace routes when I had this issue the last time and they were almost always normal.  Some of the hosts didn't respond which I understand is normal, and it connected quickly.  I don't have a ping or latency issue, my internet runs reliably smoothly except when these spikes occur intermittently. 

Once they start occurring they start happening it will go on for hours, but for better or worse I'm not experiencing it at this time so I couldn't run a traceroute with results right now.  I did not copy the information but I can tell you that the latency is under 50 ms for every hop.  I did manage to run a tracert once while the lag was occurring, and it simply timed out and/or had a delay for however long it took (around 8000 ms if I recall for that hop) and the rest were as normal, under 50ms per hop.

I just ran a tracert to google.com right now and all hops were under 30ms (save for one which was 38), but my internet is fine right now so this information likely won't help.

The latency only occurs during said spikes, and it stops entirely.  My internet is not cut off (I don't crash or disconnect) it just freezes for several moments then continues after it passes, and between those moments I have no latency issues to speak of whatsoever.  As my landline is also provided by AT&T and runs through the same connection, I can tell you that one time when speaking to customer support the issue was popping up, and when it did the phone would cut out for the period of time this happened, as well (but the call was not dropped).

I do not know if AT&T is currently offering Fiber in my neighborhood (I haven't checked, I don't really need faster internet I just need my internet to run smoothly), the only reason I mentioned it is because they had a company dig a hole in my backyard and run a line for it, and that they were preparing the neighborhood for Fiber.  (I want to emphasize that they were not installing fiber for me--it just happened that it was my backyard that they needed to dig a hole in to run lines through, apparently.)  There's a pretty good chance it's just coincidental but I started having issues with my (non-fiber, again) internet shortly after this.  My issues were resolved last time when a line was replaced by a technician who told me the line was bad, though he did not explain how the line was bad specifically or which line it was, etc.

I'm not sure how to share pictures or results of the latency, I can only tell you how long the spikes are.  This is most noticeable gaming, services that involve streaming such as video, or simply using my landline (or my cell phone using calls with wifi, for that matter) but any internet functionality I have freezes entirely.  All websites.  All services.  And again, my Arris router's log does not show abnormalities when it occurs.  It's as if the data being sent is stuck for several seconds, then finally goes through. 

However, if there is a way to actively monitor my connection then the next time this occurs I can do so and share the results, but I don't know how aside from using task manager, which doesn't measure it reliably enough to help here I suspect.

Thankfully I have only had it happen one night, and if I am lucky I won't see it again, but I'm not convinced it will be that easy.  Could this be caused by fiber lines being installed in the neighborhood?  Could it be a bad line again?  I know this is not on my end and that all services stop for several seconds when it occurs, and that this strangely had always seemed to happen very late in the evening, so I'm pretty sure it's not a matter of too many people using internet.  No other devices/etc are using the internet in my home when this happens that would be using up bandwidth to speak of, so it isn't that either.

When the technician replaced the line last time the issues went away for months, and only popped up a day ago the one time.  The reason I'm concerned is because I doubt the line is bad already (unless it was physically damaged somehow since then? unlikely...) and as elusive of an issue as this was it will be very difficult to solve if it's not that.

If it occurs again I'll run a traceroute again or anything else you might recommend to help diagnose the problem, so please let me know how best to give useful results as to what is going on.

I know I'm posting a lot here, so I'll try and be concise about what I know:

• This issue was resolved a couple months ago after several different technician visits when the last one replaced the line.  (This is the first time I've had an issue since then, and previously it was occurring on average every other night.)
• Since this issue was resolved, I've had this issue happen one night only so far.  (I made this post because I anticipate it will happen again, and I want to see it fixed properly if it does by doing all I can to diagnose it, since it did not normally happen during daytime hours.)
• All services are impacted.  I've tested this fairly thoroughly.  Other devices feel it when it happens too.
• Calls are not dropped, services are not disconnected, etc, however my internet is effectively frozen for 5-10+ seconds at a time while it occurs.
• While ongoing it will occur every 2-3 minutes usually, sometimes longer sometimes sooner, it varies but the lag spikes happen consistently for hours on the nights I have had problems.
• My latency is absolutely fine except for when these lag spikes are actually occurring.  Ping is low, and there are no abnormalities.  Under 150ms normally, so ping/latency is not the issue directly.  This includes nights where I have issues, outside of the lag spikes when they happen for several seconds of course.
• I do not use a VPN, however I tried using one to see if it would fix the issue last time, and it did not, if that helps in anyway.
• Traceroutes hops are normal (~30ms on average) even on nights this is occuring, except while said lag spikes are actively occurring where it will show latency for that hop for as long as said spike is ongoing.  (A single hop will have latency in the thousands of ms, and the rest will be normal.)
• My Arris router's logs show no abnormalities specific to when the spikes occur.  Usually not even a generic discard, which I get plenty of regularly. 
• It almost always occurs late at night, and lasts several hours on and off when it does.  It has occurred during the day, but only rarely--when it has it has been happening all night long and lasted into the next day.
• The area I live in is very hot and humid.  I know this can impact lines but normally it shouldn't be causing problems, however I think it's worth mentioning.
• I do not have fiber, but these issues happened some time shortly after they started running lines for fiber in my neighborhood.  Likely a coincidence but I don't want to discount anything.

I think that about covers what I know.  If there is anything I can do to test this, or anything I can check myself please let me know and I will do so.  If/when this issue happens again I will run trace routes while it is ongoing and try to post the results, though I suspect they will be the same (a single hop will have an excessively long latency and the rest will be normal, as before.)

Sorry for the long posts; I am trying to share all I can because this has been such an elusive and confusing issue.  Thank you for any assistance you can provide.  If there is anything else I can provide (aside from a trace route which I will run if it happens again) that might help, let me know and I'll be sure to do so.

Thank you for all of that information, TTrain750!

When you start seeing the lag spikes again, please be sure to get back to us with the screenshots of the traceroute, so we can determine what our next steps should be.

If you need help with anything else in the meantime, just let us know.

Aminah, AT&T Community Specialist

@TTrain750  First off, thank you so much for your two postings.  I'm often taken to task by some of our more rude forum members for being too wordy.  I will forever keep the link to this thread as proof that I'm not that wordy.  😁

But seriously, I understand the need to be as complete as possible, even if others immediately look for the TL;DR when they see more than a tweet-length post.

The fiber itself isn't capable of causing the issue, although I suppose it's possible that your line was damaged as a result of the fiber's installation process.  It doesn't take much to put a little nick in one of the tiny copper pairs that bring your Internet and phone to your house and that can cause issues. But the fact that it's intermittent tends to discount that sort of thing.

There are so many possible causes for latency spikes that I can't just say look for this or that.  It could be your line again, could be environmental (extremes in heat or cold can affect marginal lines), it could be something on your own network or even something that one of your neighbors is causing.  That's why we have to start someplace and try and whittle down the list based on what we see. 

So do the traceroutes during normal times and again when it spikes. Take a screen capture of the command prompt window that shows the traceroute.  Use the icon that looks like a mountain range and the moon at the bottom of the window where you create your forum comment to open a dialog where you drag/drop the screen caps.

Also, go to http://192.168.1.254/  and click on the Broadband tab.  Look for Sync rates, Attenuation, Noise Margin and Error counts and post a screencap of those sections.  Grab one when things are normal, do another when they go south and post those.

In the meantime, I suggest you go to www.att.com/availability and see if you are eligible for fiber.  If so, I suspect you'll find a package that's much faster than what you have now and it's probably either less expensive than what you pay for Internet now or the about the same for the much faster speed.  Fiber gets you off the decaying copper infrastructure that will continue to cause issues as AT&T declines to spend the money to keep it in shape.

Heh, I am not sure whether or not to take that as a compliment... but I'll give the benefit of the doubt!

Thankfully I haven't run into this issue but once since then (and it was surprisingly brief).  Also, when I talked about AT&T installing fiber I meant what you said; that the DSL line might have gotten damaged in the process. I don't know if that is what happened but I don't think that's the issue right now at least (since they replaced the line last time).

It's as you say, there could be any number of issues.  If it happens again I'll try to get the data and log it, but honestly, I'm thinking about just switching to fiber.

I did find out that fiber is in fact available now where I live, and it sounds like it will be far more reliable either way, especially since, as you put it, AT&T invests less into maintaining them over time.  So that probably will solve my problem if I do... or at least I surely hope so.

It was definitely a compliment, well, maybe "appreciation" is a better word.

Yes, if you have availability I'd say definitely pull the trigger on switching to fiber.  Make sure you place the order on att.com, since there are extra rewards for not calling in or ordering from a door-to-door salesperson.