What could cause my internet to blip out every half an hour?

[QuarterOfTen]

I posted a while ago about an issue I was having with my Internet; how it would seemingly drop at random times, but not enough for the entire network to go down (my router still says it is active). I got a bunch of advice for things to try but sadly nothing seemed to help. Nine months later, the issue is unfortunately still happening even after going back and forth with my ISP. It is not an issue of wired vs. wireless nor is it device specific, as it has happened across multiple devices both wired and wireless. After a while I started writing down every noticeable crash I experienced. At first I didn't notice anything out of the ordinary, but after the past few times I started to notice a trend - all blips in my service would happen at hour or half hour intervals of each other. Some further testing after getting more info showed that these blips are liable to happen every half hour exactly, give or take a few seconds. If my service is interrupted (for instance, due to a power outage or a tech checking the network), the exact minute it happens each hour changes, but it still can happen every half an hour (ex. if it can happen every time its xx:24 or xx:54, an outage might make it so that it happens every xx:30 or xx:00). The router doesn't say that any downtime is detected or that there's any errors logged during this time, and I also completely replaced my router from the manufacturer since this all started, so I'm thinking my router isn't the cause. I also know that more work needs to be done to my lines outside. However, since this happens at such a precise interval, I'm not sure what could be going on anymore. Does anyone have any clue as to what this could be?

 

[ARVI80]

If you are sure it is not your ISP or router then the issue is caused by a device withing your network or maybe a DDOS attack, it could even be from something like a wifi enabled lighbulb, power socket etc...

What you really need to do is disconnect everything from your router/switches/wifi and connect 1 back at a time until you find any culprits. Obviously you will need to allow every device time once connected to be certain it is not causing an issue before you add back another device.

3 other things you could try to see what happens, depending on your router model and its features are.
1: Enable the DDos protection setting withing the firewall of your router.
2: Use the QoS function on the router and see how it goes.
3: Reserve the IP addresses of your devices by the mac address in the router (this will make sure only the devices that should be handed an IP get the required access and any other rogue devices do not)

 

[tom_vrx]

I once had a similar issue with adsl line. Changing the operator to a bit more expensive one fixed the issue. The "cheap one" I was using was actually a daughter company of the one that finally worked
It was definitely a problem on their side for me - sporadic outages here and there, I guess when one of the neighbors needed more bandwidth then my line got ditched

 

[smf]

If you are using your ISP DNS server, then I would try configuring your router to use google's DNS (8.8.8.8 & 8.8.4.4). I had an ISP where things would stop working and this resolved the issue.

In the UK we have a master socket, which the ADSL should plug into with a filter. There is usually a face plate that can be removed, which has a socket behind. The faceplate connects any extensions in the house to the master socket, so by plugging the router into the socket behind the faceplate then it can rule out any internal wiring issues. I used to get drop outs in the summer when it got hot, it turned out there was some dodgy wiring in the half a dozen phone extensions. After removing them that particular issue was solved. I don't know if this easy test applies elsewhere, but disconnecting extension sockets is a good thing to try.

I also once had an issue where if the internet stopped working, I would life the receiver and tap the hangup a couple of times and it came back. My phone line was 10km of patchwork aluminium that broke every time they dug up the road to fix another line. Now I'm on Fibre to the cabinet that issue has thankfully gone.

 

[QuarterOfTen]

Thanks for the feedback guys. I do have a bit of an update; out of desperation while testing everything again I decided to purchase a completely new modem/router combo that was compatible with my ISP (Comcast; I'm in the US and they have basically a local monopoly where I'm at). Most of my problems vanished immediately. Turns out that the modem/router brand I'd been using (Motorola) has gone downhill over the past few years, to the point their dedicated customer service department just completely vanished sometime within the past two months. The manufacturer just decided one day that they didn't wanna deal with it anymore. While there were - and still are - issues with the line outside (signal levels were weird and shorts were indeed present), the most prevalent issue seems to be dealt with, which is good, expensive paperweight aside. However, unfortunately, the problems don't end there, as the modem I got has an Intel Puma chipset which has already started to show overloading. More work and research for me, so... I guess this thread can be a modem/router suggestion thread now?

 

[Psionic Roshambo]

I would recommend not using a combo modem and router first off. I can't base that on any evidence... just in my experience using two devices just seems to work better.

That being said for a wireless router I would stick to name brands... Avoid getting the cheapest thing you can get your hands on as you honestly get what you pay for, that being said the super expensive stuff probably isn't a good value for the dollar either unless you absolutely need 4,000Gbps wifi or something crazy. I tend to look for quad core a decent amount of RAM (more cores might better and more RAM is always nice.)

If you got money to burn maybe look into a router that supports open source firmware, I really enjoyed it on one I had. Very stable and had features that just turned a cheap OK router into into one I held onto until it just couldn't keep up with multiple 1080P streams...

https://openwrt.org/toh/views/toh_available_16128

https://dd-wrt.com/

 

[QuarterOfTen]

Good to know. I might give the modem/router combo one more try with Netgear (with all the work I've had to do over the last year I'm not sure I'm ready to go from one possible problem vector to two) and then if not I found a decently priced modem and router (the latter of which is on dd-wrt's index). What features are possible with open-source that wouldn't be possible on stock?

 

[Psionic Roshambo]

Good to know. I might give the modem/router combo one more try with Netgear (with all the work I've had to do over the last year I'm not sure I'm ready to go from one possible problem vector to two) and then if not I found a decently priced modem and router (the latter of which is on dd-wrt's index). What features are possible with open-source that wouldn't be possible on stock?

More control over your own network, enhanced ad blocking, IP filter lists so you can block known IP trackers, Network monitoring, there are tons of different modules you can add. To the average user, stock firmware VS open source is kinda "It works either way" but I honestly would trust the open source community more with security and updates.

The nice thing is you can try both out, Usually it's not a one way trip installing open source firmware (I say usually because there are some routers that need to have some weird things done to them if you want to go back to the stock firmware)