Internet connection coming and going I have Xfinity internet 600Mbps

[Slr8929]

On January 26, 2022 at night I completely lost internet connection and all the lights on the cable modem right router were on and green I restarted my router and had internet connection again but I called comcast anyway and they sent out a technician on January 28, 2022 the connection worked fine after I restarted the cable modem router but right before the comcast technician showed up I lost the internet connection again well the technician did all the examination, I saw through the window that he installed some stuff on the line (looked like cables) he came and tested the modem went back outside to adjust a few more things then came back inside tested the modem again and told me the internet should be working I tested it and sure thing it was working the technician told me that the signal was very bad or something like that  After the technician left the connection worked fine the 28 (the day the technician fixed it), and it worked fine the next day the 29 but on January 30, 2022 my parents were in a zoom meeting and the internet connection started going bad it was in and out I had connection but the zoom was struggling they had an error that said internet connection unstable I looked at my modem and all the lights were on and green this issue happened at 10:00am and lasted until maybe 3:00 pm so I called comcast and everythinh was ok on their end so I decided to upgrade my speed with them from 300Mbps to 600Mpbs after I did that upgrade about 20 minutes later the zoom meeting was way stable and everything was fine until 4:00pm I lost internet connection and again the lights all lights on the cable modem router were on I looked at my xfinity account and it said everything looks good so I decided to disconnect it from the power and plug it it again and that seemed to fix the problem I haven't lost internet connection at all since then, I dont know how long it will last like that I just really want to know what is going on I do have an event log picture from the morning of January 30,2022 I will attach it maybe someone can tell me why this has happened to me so that I can prevent it. Thank You All For Your Help!

[FURRYe38]

Please post a copy and paste of the modems connection status page.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

[Slr8929]

The ISP (Comcast) technician did say it was a signal problem when he went on Friday January 28,2022 and was told by the tech that he fixed that problem.I forgot to mention I have a AC750 WiFi Range Extender (EX3700) It is near the backyard door not near the cable modem/router could this be an issue?I have this bcause my house is about 1,300Sq.FT it is a one story home, I am not currently home so I can't post the modems connection status page but I will do that once I get home I did call my mom and she says that the Internet is currently working. I checked that there are no coax cable line splitters in the between the modem and ISP service box, Iam  using good quality RG6 coax cable up to the modem because that was installed by Comcast I've had Comcast sine November so the coax cable is fairly new. In the event log I uploaded there was a T4 timeout at the top what exactly does that mean?

[FURRYe38]

Something to turn OFF is the extender while you troubleshoot the modem to be sure it's working well. 

[Slr8929]

I will try disconnecting the extender from the wall and see if that resolves my issue. I read in the product description of the nighthawk c7000v2 that this product has High-powered amplifiers so I think the exentender could be messing up my signal instead of helping it. When I get home I will try disconnecting the extender and see if I stop having the no internet connection issue. I will let you know if that works. 

[FURRYe38]

Also the EX3700 would not be a good match for the C7000, the EX7000 would, IF an EX is needed. For a 1300 sq ft home a EX shouldn't be needed if the modem is placed centrally in the home on the main floor. 

[Slr8929]

Ok so I disconnected the extender and seems to be working fine im attaching upstream and downstream logs I think they are ok but I need someone to take a look at them thanks!

[FURRYe38]

Power levels maybe a bit too high.

https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311

Correctables and Uncorrectables are zero which is good. Might ask the ISP to maybe turn down the power a couple of notches? 

[Slr8929]

The isp (xfinity) said the power levels were within specs so I don’t know, I haven’t lost internet connection since 4:00pm Sunday January 30,2022 but now my wifi speeds are very slow they also told me my receive powers are a bit low, again I don’t know anything about that either

[FURRYe38]

If power levels are low then they need to help with that. Ask them to send out a tech and have them check all cabling, connections and signals up to the modem to be sure. 

[Slr8929]

Ok so I haven’t had any loss of internet connection since January 30,2022 but I have like 14 devices on my wifi, I will be disconnecting 3 of them since I don’t actually need them, so here is the thing I have 2 zoom meetings at 7:30pm today one is my parents on a laptop and I will be on the other zoom meeting on my laptop both laptops use the same wifi but I recently discovered that I can connect one of my laptops to 5ghz and it should be fast enough for one of the zoom meetings the speed test on the laptop that will be connected to the 5ghz is 170Mbps is this good enough the only other thing streaming at the same time during the zoom meetings are a ring doorbell a dog cam and my 4 security cameras that are connected through Ethernet, also the speed I’m currently getting from xfinity when on Ethernet is 300Mbps I pay for 600Mbps with all this in mind will I run into problems when I connect to the zoom meetings

[FURRYe38]

4 security cameras could be impacting performances as well. 

[Slr8929]

So What can I do so that I don’t get any timeouts when in the zoom meetings today?

[FURRYe38]

I would try this, turn OFF the cameras before your zoom meeting and see if this changes behavior. 

Also any chance you can ethernet connect your zoom pc to the modem? 

[Slr8929]

I can connect one of the laptops to Ethernet I have two zoom meetings at the same time because my parents also have a zoom meeting but their laptop will have to be on wifi 5ghz

[FURRYe38]

Ok, see how that works, with the cameras OFF. 

Wondering if bandwidth is getting starved with having two zoom meetings and all cameras going at the same time and modem is having problems with it. 

[Slr8929]

Ok so I have an update I am getting the speed that I pay for (600Mbps) when I connect my laptop to ethernet but when I connect my laptop to the wifi on 2.4ghz I get download speeds in the 70-80Mbps when I connect it to the 5ghz I get 100-200Mbps download speeds I have been told that those wifi speeds are still low that they should be higher when I test the wifi speed I test it right next to the nighthawk cable modem router, so Im not sure if there is something wrong with the cable modem router. Im sorry for all the questions Im just trying to understand what exactly is going on with my wifi.

[FURRYe38]

Ok, so for 2.4Ghz you'll not see much over 100Mbps and also depending on your client HW support this may be lower. 2.4Ghz N mode if you connect at 300Mpbs, usually maxes out at 100Mpbs, if that. Many variables here.

Same goes on 5Ghz, depending on connection rate, 5Ghz on AC mode maxes out at around 300-500Mpbs, again depending on client HW support and design. So you are in the ballpark on speeds. 

Wired you should need your 600Mpbs. 

Need to check the connection rates seen on the client device and see what it's connecting at the modem. 

[Slr8929]

I have an update on my speed situation I had another xfinity technician at my house and he told me everything was okay but he recommended that I get a new cable modem router combo because the one I currently have the nighthawk C7000v2 with DOCSIS 3.0 is not good enough for my current speed of 600Mbps he said I should get a Cable modem router that has DOCSIS 3.1 and well now I ordered the Nighthawk C7800 with DOCSIS 3.1 my brother has this one and has xfinity also and he hasn’t had any issues in fact he gets wifi speed of almost 200Mbps download on the 2.4ghz and on the 5ghz he gets about 300Mbps so it seems that this new modem will work better I will let you know if my speeds improve with this modem.

[FURRYe38]

👍

[Slr8929]

I received my new cable modem router the nighthawk C7800 so far it seems to be working fine I tested the wifi speeds before connecting my devices on 2.4ghz it’s about 48Mbps next to the modem, on this connection I have 8 devices connected (I haven’t tested the speed after connecting the devices) on the 5ghz before connecting devices I testes the speed right next to the modem and it was 239Mbps I tested it again a few minutes Later with no devices connected yet only the laptop that I was using to test speed and it was about 290Mbps, right now I have a 2 tvs connected on this connection the 5ghz (laptop is only connected when I’m using it for zoom meetings) so for the zoom meetings I mentioned previously that when connected to a zoom meeting on the laptop the 5ghz wifi would drop, i connected to a meeting today before all the devices that I mentioned were connected to wifi and the 5ghz did not drop tomorrow I have another zoom meeting I will see if it will not drop now that I have my devices connected again. It seems to look like the old modem the nighthawk c7000v2 was defective but I guess I will find out tomorrow when I connect to my zoom meeting again with all devices connected I also have yet to try to connect to 2 different zoom meetings at the same time on different devices hopefully I will be able to do that without any issues using my new modem the nighthawk C7800

[FURRYe38]

Let us know how it turns out. 

[Slr8929]

ok so I have another update on my Wi-Fi connection situation, on Wednesday my dad had a zoom meeting on his iPad using the 5ghz and it was fine the zoom meeting was done without any issues, today he connected to a zoom meeting using the same 5ghz connection and the same iPad and all of a sudden the zoom application kicked him out and he could not reconnect to the meeting I changed his Wi-Fi connection to the 2.4ghz and it worked fine (both meetings were also done in the room next to mine with the door to that room closed and the door where the nighthawk is was open, the nighthawk C7800 is in my room),I'm wondering why the connection dropped when this happened all other devices never lost internet connection his iPad the one used for both meetings never lost internet connection because he was still able to acces websites so what is going on?

[FURRYe38]

Is WiFi Private Address enabled on the iPad? If so, try disabling it and test a zoom call on 5Ghz. 

How is the 5Ghz radio configured currnently on the modem?