Intermittent Disconnects CGN3ACSMR

[jerkbag]

Hi -- I recently signed up for an ignite 250mpbs internet package after being with TekSavvy for years. I am experiencing intermittment disconnects -- usually once a day in the evenings, and they are usually resolved with a modem reboot. The DOCSIS log fills with "No Ranging Response received - T3." Other then these outages, the service seems to run well and I am getting farily consistent 250mpbs speed. The signal levels seem fine when it's working, but I have yet to caputre some when it goes down. 

I live in a house, downtown toronto. 100+ years old, mess of wires and cables running from poles in the backyards of the street. Based on reading here it looks like this could be a cabling issue? Any advice in the steps needed to get a ticket and/or tech out if necessary? My attempt at rogers support just has techs telling me to reboot the modem. 

Any advice apprecited -- thanks! 

[Datalink]

Can you log into the modem, navigate to the DOCSIS WAN page, copy the downstream and upstream tables and paste them into a thread.  Just the tables, and none of the data above the downstream table which includes the MAC Address.  The copy and paste process will paste in the text contents into the post.  Those are the downstream and upstream signal levels which will be of interest at the present time.

[jerkbag]

Thanks. Here's what it looks like now (net working fine). I will try and grab one the next time the connection drops. 

Downstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Signal noise ratio (dB)
1	633000000	256QAM	-7.200	37	38.605
2	621000000	256QAM	-5.600	36	38.983
3	639000000	256QAM	-7.100	38	38.605
4	645000000	256QAM	-6.400	39	38.983
5	651000000	256QAM	-6.700	40	37.356
6	657000000	256QAM	-8.300	41	37.356
7	663000000	256QAM	-8.500	42	37.356
8	669000000	256QAM	-7.400	43	37.636
9	675000000	256QAM	-7.100	44	38.605
10	681000000	256QAM	-7.100	45	38.983
11	687000000	256QAM	-8.000	46	37.636
12	693000000	256QAM	-7.400	47	38.605
13	699000000	256QAM	-5.800	48	38.983
14	705000000	256QAM	-6.700	49	38.983
15	711000000	256QAM	-8.000	50	37.636
16	717000000	256QAM	-8.500	51	37.636
17	723000000	256QAM	-7.900	52	38.605
18	825000000	256QAM	-10.800	53	37.636
19	831000000	256QAM	-11.700	54	36.387
20	837000000	256QAM	-12.400	55	36.387
21	843000000	256QAM	-11.900	56	36.387
22	849000000	256QAM	-11.400	57	36.387
23	855000000	256QAM	-13.000	58	35.780
24	861000000	256QAM	-13.300	59	35.084

Upstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	BandWidth
1	38596000	ATDMA - 64QAM	52.500	6	3200000
2	30596000	ATDMA - 64QAM	52.250	4	6400000
3	10000154	ATDMA - 64QAM	50.250	---	6400000

[Datalink]

@jerkbag you have serious signal issues on the go.  Call tech support and advise the CSR that you have signal levels on the downstream side that are below -10 dBmV and that you only have two upstream channels running instead of three.  Ask the CSR to run a signal check on the modem.  That check should fail automatically and the next discussion should be about getting a tech to your home at your convenience.  

If you have any problems with tech support, please let us know.  This should be a straight forward conversation: Bad signal levels ---  need tech.  End of discussion.

Please let us know what occurs.

[jerkbag]

Thanks for you help -- I guess I can't read those signal levels as well as I thought I could 🙂

I called Rogers just now and they did a test and are sending out a tech.

Thanks!

[jerkbag]

Update -- tech came by today, and traced the problem to an ancient looking rusty splitter inside the locked rogers box outside the house. There was a strong signal coming into the box, and removing the splitter put everything in back in spec. 

Thanks for the help here, and to rogers for a quick solution!

[Datalink]

Can you post the signal levels again so we can see the current result?

[jerkbag]

sure -- new and improved below

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Signal noise ratio (dB)
1	621000000	256QAM	-2.300	36	40.366
2	615000000	256QAM	-2.100	35	38.605
3	633000000	256QAM	-3.900	37	38.605
4	639000000	256QAM	-3.500	38	38.605
5	651000000	256QAM	-3.500	40	37.636
6	657000000	256QAM	-4.700	41	37.356
7	663000000	256QAM	-4.400	42	37.636
8	669000000	256QAM	-3.700	43	38.605
9	675000000	256QAM	-3.800	44	38.605
10	681000000	256QAM	-3.400	45	38.983
11	687000000	256QAM	-3.900	46	38.605
12	693000000	256QAM	-3.500	47	38.605
13	699000000	256QAM	-2.200	48	40.366
14	705000000	256QAM	-3.000	49	38.983
15	711000000	256QAM	-3.900	50	38.605
16	717000000	256QAM	-4.500	51	38.983
17	723000000	256QAM	-3.900	52	38.605
18	825000000	256QAM	-6.800	53	38.605
19	831000000	256QAM	-7.000	54	37.636
20	837000000	256QAM	-7.800	55	37.636
21	843000000	256QAM	-6.800	56	37.636
22	849000000	256QAM	-7.200	57	37.356
23	855000000	256QAM	-8.300	58	37.356
24	861000000	256QAM	-8.500	59	37.356

Upstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	BandWidth
1	30596000	ATDMA - 64QAM	36.500	4	6400000
2	38595824	ATDMA - 64QAM	36.500	6	3200000
3	23700000	ATDMA - 64QAM	36.500	5	6400000

[illiterate]

Rogers CGN3ACSMR - wifi constantly dropping

About a day or two ago I noticed my WiFi has been constantly dropping. Ethernet is fine. I've tried rebooting the modem countless times but the issue reappears after a few minutes. I've also done a factory reset, but the issue reappeared after a bit. I am not in bridge mode.

Some information:

Downstream/upstream stats: 

Any idea what may be causing this? I first noticed it around Thursday night.

Thanks.

[Datalink]

@illiterate can you delete the System Information block please.  Its not a good security practice to leave MAC addresses and IP addresses exposed in an open forum.  The signal levels can remain. 

For the wifi, this might be caused by anything, but, I would suspect that a neighbor may have set up a new modem or router which is competing with your modem for a clear wifi channel.  So, can you check/set the following 2.4 Ghz wifi parameters:

Wireless Mode:  802.11 n

Channel Bandwidth:  20/40 Mhz, although, for test purposes you could set this to 20 Mhz.  In a crowded wifi environment, I would set this for 20 Mhz.  It would most likely default down to 20 Mhz anyway.

Wireless channel:  AUTO or, to an open channel if one existed, or to the channel that offers the least interference from neighboring routers and modems

WPS Enabled:  OFF

Security Mode:  WPA-Personal

Auth Mode:  WPA2-PSK

Encrypt Mode:  AES only

Save the setting and ensure that the Encrypt Mode stays on AES only.  If it changes on its own to TKIP/AES, change it back to AES only and save the setting again.  TKIP is no longer secure and will cause the wifi data rates to cap at 54 Mb/s which is the 802.11g rate.

Check/set the following 5 Ghz wifi parameters:

Wireless Mode:  802.11 a/n/ac mixed

Channel Bandwidth:  80 Mhz, although, for test puposes you could set this to 40 Mhz.  I would revert back to 80 Mhz after running a 40 Mhz test.

Wireless channel:  149 to 161

WPS Enabled:  OFF

Security Mode:  WPA-Personal

Auth Mode:  WPA2-PSK

Encrypt Mode:  AES only

Once again, save the setting and ensure that the Encrypt Mode stays on AES only.  If it changes on its own to TKIP/AES, change it back to AES only and save the setting again.  

Reboot the modem if you had to make any changes, ADMIN ..... DEVICE RESET .... Reboot.

Next look at your wifi environment using one of the following applications:

http://www.techspot.com/downloads/5936-inssider.html

https://www.acrylicwifi.com/en/wlan-software/wlan-scanner-acrylic-wifi-free/

http://www.nirsoft.net/utils/wifi_information_view.html

Or,

For IOS

https://itunes.apple.com/us/app/network-analyzer-lite-wifi/id562315041?mt=8

For Android

https://play.google.com/store/apps/details?id=com.farproc.wifi.analyzer&hl=en

In the modem itself, if you have a CODA-4582, there is a wifi Site Survey under ADMIN .... DIAGNOSTICS.  Since it uses all three of the 2.4 Ghz antenna and all four of the 5 Ghz antenna, its fairly sensitive compared to a laptop or phone.  The user interface isn't great, but, you can copy all of the data in one go and dump it into something like MS Excel, where you can sort it any way you want.

My personal choice is InSSIDer.  That's the last freebie version of inSSIDer and at this point in time is getting a little old.  Its fine for 2.4 Ghz application and does work for 802.11n 5 Ghz networks.  It does display 802.11ac networks but not as well as it should.  This has become a licenced application now for $20 US and works very well for both frequency bands, 2.4 and 5 Ghz.  

The other applications are fine for 802.11ac.  Acrylic is graphical, WifiInfoView is text only.  

What you want to do is determine what channels in the 2.4 Ghz band offer the least number of users, and in the 5 Ghz band, what channels in the 149 to 165 range are occupied and if so, which offers the least competition in terms of occupancy or signal level for any given channel.  If you can find a channel or channel range in that group that is not occupied, that will be the best choice.  

Ok, have a look at the wifi settings and at the number of users in the 2.4 and 5 Ghz bands and see if your able to find a better channel to use for your own wifi network. 

[illiterate]

Welp. Good idea. Completely forgot that.

Should be gone now.

[Datalink]

Thank you  🙂

Your cable signal levels and signal to noise ratios are fine.  I wouldn't expect to see any issues with those levels unless there are very fast transient conditions occurring which those tables won't show.  Based on your comments I suspect that this is only a wifi issue, so, a little fine tuning and examining the wifi environment might resolve the problems.  

[illiterate]

Where do you want to start 😄

[Datalink]

First thing to do is to review the wifi encryption settings.  Set those as indicated, or simply check to see if you already have those set as indicated.  Reboot the modem if you do have to change anything.  

After that, consider downloading and installing InSSIDer.  Have a look to see who else you're competing with for clear channels and adjust your wifi channels if necessary.  You might come to the conclusion that there is no good "clear" channel range.  Thats the situation that I'm in, competing both of my immediate neighbors for the upper 5 Ghz channels, 149 to 161.  Despite the fact that we're all in that channel space, the wifi rate is still faster than running at the lower channel 36 range where there is less competition.  Thats due to the fact that the upper 5 Ghz channels can run at 1 watt, versus the 50 or 200 milli-watt limits on the lower channel range.  That limit depends on when the device was approved by Industry Canada.   Increased power levels in the upper range translate to increased signal levels and better signal to noise ratios.  

[illiterate]

For the WiFi encryption settings, am I missing something? You mentioned to set them as indicated but I don't see what you've indicated. Thanks!

[Datalink]

Ok, log into the modem and navigate to WIRELESS....BASIC SETTINGS....2.4G to start.  Each of those user selectable items, Wireless mode, Channel Bandwidth, Wireless Channel, etc, etc, have more than one selection available on the right hand side of the indicated item.  Go thru those settings, and match the selectable items in the modem drop down menu items to what I have indicated in my previous post.  That will ensure that the modem is operating with the highest level of encryption which can affect the data rate if not selected properly, and that the bandwidth is set to an appropriate setting.  

As an example, the Wireless Mode has more than one selection available.  My personal recommendation is to set that for:  802.11 n  unless you happen to know that you have old 802.11b or g  devices that you still happen to use, in which case you would choose a mixed mode, b/g/n.   

When that page is complete, save the changes and switch to the 5G tab and repeat the process.  Save the changes.  

If your settings for each item are already set as I have indicated in that list, thats good news.  If you go from using TKIP to AES, thats even better news.  

So, it should be a fairly simple process to check each user selectable item against the list that I provided.  

[illiterate]

Appreciate your help. I'll go through these once I get the chance and let you know of the outcome. Probably by tomorrow afternoon.

[Datalink]

🙂  no problem.  It might only take a couple of minutes to scan through those settings when you're logged into the modem and looking at the 2.4 and 5G tabs.  If they're set to a different value, change the selection to what I have indicated.  To set the channels to something that would be productive, you would need to have inSSIDer loaded on a laptop and have the application up and running so that you know which channels are crowded with users and which are open or less crowded.  Won't know until you have the application running.  The display is pretty straight forward to understand, shows 2.4 GHz band on the lower left, 5 Ghz band on the lower right, with all of the networks that the laptop can detect from nearby modems and routers displayed in the appropriate area.  You might be surprised by the number of users nearby if you've never looked at it before. 

[maildc16]

Hello - I have a similar problem where my internet connection drops and then reconnects. The re connection usually happens within a minute. However, the drops are quite frequent ranging from 10-25 per day making it a frustrating browsing experience. What could be wrong with my connection?

[Datalink]

@maildc16, drops for wifi, wired or both?

Can you log into the modem, navigate to the STATUS  .... DOCSIS WAN tab, copy the signal level table, from the "Downstream Overview" all the way to the bottom and paste that into a post.  The copy and paste process will paste in the text contents of the table.  

[maildc16]

@Datalink : Thank you for the prompt response. 

The connection drops for both wifi and wired.

Just to give you some background on this  : Unlike sites like Youtube where the content is buffered and therefore will usually not indicate that there has been a connection drop unless it is for an extended period,I have a corporate VPN that I connect to when working from home and that disconnects (and then tries to reconnect) as soon as the drop happens even if for a very brief period. Therefore I am usually aware when the drop happens (which is happening quite often now), which otherwise would have been very easy to miss given the very short duration of the outages.

Update : Web support asked me to change the modem. I am not convinced this a modem issue but I am not an expert either so will look forward to your expert advice

Here are the signal levels :

Downstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Signal noise ratio (dB)
1	591000000	256QAM	1.000	7	40.366
2	579000000	256QAM	1.000	5	40.946
3	585000000	256QAM	1.000	6	40.366
4	303000000	256QAM	0.200	1	40.366
5	597000000	256QAM	1.000	8	40.366
6	603000000	256QAM	1.100	9	40.946
7	609000000	256QAM	1.300	10	40.366
8	615000000	256QAM	0.700	11	40.366
9	621000000	256QAM	0.500	12	40.366
10	633000000	256QAM	0.300	13	38.983
11	639000000	256QAM	0.600	14	38.983
12	645000000	256QAM	0.400	15	38.983
13	651000000	256QAM	0.100	16	38.983
14	657000000	256QAM	0.000	17	38.983
15	663000000	256QAM	-0.400	18	38.983
16	669000000	256QAM	-0.400	19	38.983
17	675000000	256QAM	-0.500	20	38.605
18	681000000	256QAM	-0.900	21	38.605
19	687000000	256QAM	-0.600	22	38.983
20	693000000	256QAM	-0.400	23	38.983
21	699000000	256QAM	0.000	24	38.605
22	705000000	256QAM	0.100	25	38.983
23	711000000	256QAM	0.200	26	38.605
24	717000000	256QAM	0.100	27	38.605

Upstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Bandwidth
1	23700000	ATDMA - 64QAM	42.750	2	6400000
2	38596000	ATDMA - 64QAM	44.250	3	3200000
3	30596000	ATDMA - 64QAM	43.250	1	6400000