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Tom Baxter
@68.60.247.x

Tom Baxter

Anon

[Connectivity] Comcast Connection Suffers - No Explanation

I was hoping someone might have a clue as to what's causing my Internet problem, since Comcast is clueless, despite two visits from "technicians". I am seeking some advice as to what I can tell Comcast when the third technician arrives next weekend.

I am currently on my third modem/router in three months (so I doubt the problem is with the modem/router). The current modem/router is a Netgear C3700. Prior to that I had two Motorola SBG6580 devices. My Internet connection behaves the same regardless of which modem I use.

I'm running two Windows 7 machines and a Windows 8 machine. The problem I see occurs on both wired and wireless connections and on all three machines.

Let me describe the symptoms and the experiment I've run.

The symptom is that web pages take a very long time to load and very often timeout before loading completely. Often, when a page does load, it only loads partially, with images, JavaScript or CSS files failing to load.

Let me describe the "experiment" I perform.

I open a Google page and search for, say, "national news". Then, I open about 15 of the search results, each in its own browser tab. As the 15 tabs are loading, I open the "Networking" tab in Task Manager to watch the networking activity as these 15 tabs are loading. What I see is virtually no network activity. My "Networking" activity is almost completely flat-lined as these pages attempt to load.

Of the 15 tabs loading, usually 2 will load completely, another 3 will load partially and the rest will time out completely.

If I take my laptop to a local Wi-Fi hotspot or to a friend's house and run the same experiment, everything works fine -- all the pages load to completion. Similarly, if my friend brings her computer to my place, she has exactly the same problem -- nothing loads.

If I run any of the many Internet Speed Tests, I see I have good speed -- always over 25Mbs. Sometimes, however, my browser cannot connect to the Speed Test web site, which is consistent with the problem I'm having. When it does connect and I'm able run the test, the speed is great.

My intuition tells me that my machines are having problems establishing connections. Once established, however, the speed is great. The problem might have something to do with the initial TCP/IP handshake or something.

I've had two Comcast techs here to troubleshoot and they could not find anything wrong. They said the signal is strong and the speed is good. They have no idea. Another Comcast guy is coming next weekend and he's bringing his own Comcast modem. If anyone has an idea of what might causing this problem, please let me know. I feel this problem must have something to do with Comcast since I've had three modems and the problem only occurs at my place.

Thanks very much.

cHarley
join:2013-07-10
Boynton Beach, FL
Motorola MB8600
(Software) pfSense

cHarley

Member

Have you tried changing DNS servers? On one of the systems, open the Network Adapter Settings select IPV4 then Properties and select Use The Following DNS and try Google's DNS at 8.8.8.8 and 8.8.4.4.

While you're there, also try disabling IPV6 if it's enabled.

See if these settings make any difference.
djlandkpl
join:2007-12-27
Norton, MA

djlandkpl to Tom Baxter

Member

to Tom Baxter
What are your upload speeds when you run the speed tests. It would help to post your modem signal stats.

beachintech
There's sand in my tool bag
Premium Member
join:2008-01-06

beachintech to Tom Baxter

Premium Member

to Tom Baxter
Do you have this problem if you take one of your computers and use a different internet connection?

telcodad
MVM
join:2011-09-16
Lincroft, NJ

telcodad

MVM

said by beachintech:

Do you have this problem if you take one of your computers and use a different internet connection?

Well, Tom Baxter said:
said by Tom Baxter :

:
If I take my laptop to a local Wi-Fi hotspot or to a friend's house and run the same experiment, everything works fine -- all the pages load to completion. Similarly, if my friend brings her computer to my place, she has exactly the same problem -- nothing loads.
:


Tom Baxter
@68.60.247.x

Tom Baxter to djlandkpl

Anon

to djlandkpl
The upload speed is also decent -- around 6Mb.
Tom Baxter

Tom Baxter to cHarley

Anon

to cHarley
I tried but it didn't work. It's the same problem.
bonk27
join:2011-12-30
Salem, OR

bonk27

Member

Try turning Qos of on your router
dudeofmoose
join:2011-07-19
Stockton, CA

dudeofmoose to Tom Baxter

Member

to Tom Baxter
A long shot... but what is your power source? Was it the same one used for all three modems? Do you know your neighbor well enough to take the modem to their house and try it there? Cable/splitters? (I'm guessing with 2 techs they would have HOPEFULLY checked the signal strength... *knock on wood*)

Long story short, my Cyberpower 1500avr UPS was the cause of my last major issue (I had ran coax into the ups for surge protection).

Last year I had a similar issue where all of a sudden my connection became very poor. I could start streaming a single video (netflix... mind you I had 50/10 plan, and speed tests usually stayed steady at 57/11) but the initial buffering would be 4 times longer and once it started if be back to buffering pretty quick. Devices would connected to the interwebs but browser pages took forever or timed out. speedtest.net showed an outrageous ping time (I'm normally 20-40ms but it was in the 500s)

So after checking my modem logs, I had really high uncorrectables on 1 channel, and a large amount of correctables on several other channels. Stumped, I moved modem to the bedroom cable hookup, and it had reduced the number of errors but not back to the normal level.. Not wanting the modem, and router flashing away in the bedroom, I went back to the living room to troubleshoot (splitters/cable etc) no real luck. I had a spare modem (when I upgraded 4x4 to 8x4) and hooked it up, same high number of errors(ie modem not problem). Seriously stumped and getting ready to set up my 4g hotspot as a backup while I call comcast for a troubleshoot, I noticed my power strip had "wiring fault" led lit. I looked back at my UPS where my network equipment was hooked up, it's wiring fault led was lit too. So I shut down/unplugged my equipment, shut down the UPS, at which point my power strip on the same circuit but not hooked up to the UPS, its fault led turned off. I power cycled all the breakers anyhow and hooked everything back up and no trouble since then.

I no longer run the coax through the UPS, (using a monster power tap for non-ups items) and I haven't had a repeat of the issue. I can't say for sure it was the UPS injecting noise onto the line.

Wayne99021
Premium Member
join:2004-12-28
Mead, WA

Wayne99021

Premium Member

It must be a Cyberpower thing.
had the exact problem with the 1500AVR.
I found mine by chance. Had to move the UPS and didn't have enough RG6 at that time so just put a barrel connector inline. The trouble went away. Just to make sure, I plugged the RG6 back in the UPS and the trouble came back. Did that 3 times in all.
I contacted Cyberpower support and they acted like I was smoking some good stuff because that just can't happen.
Have left the coax out of the UPS and all is golden.

telcodad
MVM
join:2011-09-16
Lincroft, NJ

1 edit

telcodad

MVM

said by dudeofmoose:

A long shot... but what is your power source? ...

Long story short, my Cyberpower 1500avr UPS was the cause of my last major issue (I had ran coax into the ups for surge protection).
:
I no longer run the coax through the UPS, (using a monster power tap for non-ups items) and I haven't had a repeat of the issue. I can't say for sure it was the UPS injecting noise onto the line.

said by Wayne99021:

It must be a Cyberpower thing.
had the exact problem with the 1500AVR.
I found mine by chance. Had to move the UPS and didn't have enough RG6 at that time so just put a barrel connector inline. The trouble went away. Just to make sure, I plugged the RG6 back in the UPS and the trouble came back. Did that 3 times in all.
:
Have left the coax out of the UPS and all is golden.

Yes, many of those built-in coax surge protectors in some UPSs and combination AC/telephone/RF surge protection devices are known to cause ingress noise issues.

You have to make sure you use a separate, quality RF surge protector that has low insertion loss up to 1GHz.

While I have all my equipment plugged into an APC UPS (w/surge protection), I didn't use the built-in coax surge protector on that, but went ahead and replaced my ground block with this TII 212 coaxial surge protector: »www.digicomm.com/tii210.pdf

I bought mine on Amazon: »www.amazon.com/TII-Broad ··· 016AIYU6

Wayne99021
Premium Member
join:2004-12-28
Mead, WA

Wayne99021

Premium Member

So you just replace Comcast's ground block with this unit?
Sure makes a lot more sense than running it though the UPS.

telcodad
MVM
join:2011-09-16
Lincroft, NJ

telcodad

MVM

said by Wayne99021:

So you just replace Comcast's ground block with this unit?

Yeah, no problem, even the screw holes were spaced the same as for the ground block.

I figured it would be best to arrest any surges before they even got into my home.

Wayne99021
Premium Member
join:2004-12-28
Mead, WA

Wayne99021

Premium Member

Thanks for the info, I will be ordering one.
Have been a little paranoid not having protection on the RG6 coming in and this will take care of that.
Thanks again.
tlbaxter
join:2014-09-28
USA

tlbaxter to Tom Baxter

Member

to Tom Baxter
I have the answer to my problem.

The "problem" was that I was using one of the modem/router all-in-one devices. These devices were blessed by Comcast as "compatible" but it seems the reality is much different. All three Comcast technicians who visited my home over the past three months recommended against the all-in-one device. The technician who came yesterday replaced it with a stand-alone modem and my Internet came back to life!

The "experiment" I described in my OP works just fine now.

I guess the rule is that despite what Comcast says, to be safe, you are better off going with the a stand-alone modem and router rather than a single all-in-one device.

Thanks to all those who responded...and thanks to Best Buy for allowing me to return the all-in-one device even though the 15 day return window had expired.