CODA-4582 - Open Issues for Investigation

[RogersDave]

*** This post was last edited May 2, 2017 ***

Good morning Community,

As I mentioned in a post two days ago, we have received the next firmware 2.0.10.20 from Hitron. We are currently running initial testing on this version and will push it out to participants in the firmware trial program as soon as it passes initial testing.

However, while running these tests, we discovered abnormal behavior with ICMP and are awaiting feedback from Hitron today to asses how this will be addressed. As soon as I this is confirmed, I’ll update the change log with the correct version information and start pushing it out.

In parallel, we are still working on the following high priority items. In some cases below, I requested affected customers to reach out to me via private message. If you do so, please include your modem MAC address in the subject line (even if we exchange messages daily) as there are a lot of you reaching out to me daily 🙂

UDP Packet Loss

The investigation for what has been reported as UDP packet loss is still ongoing. We have deployed a probe at one fellow forum member on both a CODA-4582 and a CGNM-3552 to collect additional data. We are actively working with Hitron and Intel on the results observed.

Based on what we know so far, in most instances UDP packet loss is coupled with higher uplink usage in the area. Although the impact is noticeable in specific logs (League of Legends), the root cause for the perceivable impact (while playing) is likely related to bufferbloat (see next issue).

Bufferbloat

When comparing the performance of a CODA-4582 to a CGNM-3552 in the same network conditions, the CODA-4582 consistently reports higher bufferbloat when tested on DSLReports.

Update April 12: The solution for this problem will come in two folds. It will require a change in software which will possibly be included in 2.0.10.27 but more likely in 2.0.10.28 and a change in network configuration.

The network configuration change is not compatible with the current firmware so this change will only come after a vast majority of the modems are running the new code. We are however looking at a way to make the change only for specific modems to support testing in the community.

Update April 22: This problem seems resolved in firmware 2.0.10.27

5 GHz WiFi Low range for channels 36 to 48

Lower WiFi channels on the modem have a much smaller range. This is due in part to the limit imposed by Industry Canada to maximum transmit power.

Furthermore, the current automatic channel selection (auto mode) tends to select the lower channels when in similar load conditions.

Workaround: manually select higher channels (149-153-157-161)

Update April 22: The channel selection algorithm has been improved in firmware 2.0.10.27

Loss of OFDM Channel Lock

Under some RF conditions, the modem fails to lock properly on the OFDM channel. This typically result in variable performance.

Update April 12: This problem is resolved in 2.0.10.26T2

List of connected device does not get fully populated

This is a known issue that has been tracked since firmware 2.0.10.13. We are making improvements at every firmware but it is not a perfect system.

The situation is worst after a reboot or firmware upgrade as the list gets reset and must be repopulated as devices renew their DHCP lease.

NAT Loopback not working for wired clients

When setting up port forwarding to an internal server, it is possible for a client on WiFi to reach the server using the external IP/port. If the client is on a wired interface, it doesn't work.

Update April 12: This problem is resolved in 2.0.10.26T2 (not confirmed)

LAN Counters not working

Some customers reported that LAN counters (especially in bridge mode) are reporting inaccurate values.

This problem has been reported to Hitron for investigation.

Unexpected modem reboot

Some customers reported their modem reboots unexpectedly. We have also seen this behavior in our lab.

Update April 12: This problem is resolved in 2.0.10.26T2

Missing SC-QAM Channels

After a reboot, some modems are missing SC-QAM channels. A fix has been implemented in 2.0.10.26T2 to address this behavior but it has not corrected all scenarios.

Investigation continues with Hitron.

WiFi Survey

The WiFi Survey functionality in firmware 2.0.10.26T2 (and possibly before) reports incorrect SSID names.

Guest Network

When connecting to the Guest Network, an error message is displayed "only allow DHCP client to use this wireless".  This has been reported in firmware 2.0.10.26T2.

Update April 22: This issue has been resolved in firmware 2.0.10.27

Update May 2: It seems this issue is not fully resolved and still experienced by some users

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Future Planned Improvements

The following are items that we are working on in parallel of the above.

• Improvement in WiFi speeds
• Improvement in latency / bufferbloat

Dave

*Edited Labels*

[Jeffj]

Sorry about the spelling and what not i'm on my cell and im fairl fat fingered and i cannot get the "edit post" to load on my mobile browser. 

[Datalink]

All of your signal to noise ratios for the DOCSIS 3.0 channels are a little low, but, if tech support can't see those numbers there isn't much that they can do.  My interpretation of that would be that there is something in the system that is causing noise ingress.  Yes, those levels might still be within spec, which is a good question, but, they are a little lower than we normally see.  Usually those levels are in the 36 to 40 dB range.  I would call tech support back to see if they've managed to get their data system up and running again.  The question that should be asked is, what are your noise levels compared to the neighbors levels, and possibly for modems further upstream?  Where is the noise entering the system.  The tech should be able to start tracking that down, if the system is up and running. 

So, if there is noise in the system, what is that doing to your DOCSIS 3.1 signal level?  The data that is presented in the OFDM section of those tables isn't correct, so you would have to ask tech support what the real numbers are. The DOCSIS 3.0 signal levels themselves are ok, both downstream and upstream. 

Are you able to switch the pingplot to ping the CMTS, which is the IP address just beyond the modem?  That would help in terms of seeing exactly what's going on between the modem and the CMTS, removing any network issues beyond the CMTS.

[Jeffj]

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@Datalink wrote:

All of your signal to noise ratios for the DOCSIS 3.0 channels are a little low, but, if tech support can't see those numbers there isn't much that they can do.  My interpretation of that would be that there is something in the system that is causing noise ingress.  Yes, those levels might still be within spec, which is a good question, but, they are a little lower than we normally see.  Usually those levels are in the 36 to 40 dB range.  I would call tech support back to see if they've managed to get their data system up and running again.  The question that should be asked is, what are your noise levels compared to the neighbors levels, and possibly for modems further upstream?  Where is the noise entering the system.  The tech should be able to start tracking that down, if the system is up and running. 

So, if there is noise in the system, what is that doing to your DOCSIS 3.1 signal level?  The data that is presented in the OFDM section of those tables isn't correct, so you would have to ask tech support what the real numbers are. The DOCSIS 3.0 signal levels themselves are ok, both downstream and upstream. 

Are you able to switch the pingplot to ping the CMTS, which is the IP address just beyond the modem?  That would help in terms of seeing exactly what's going on between the modem and the CMTS, removing any network issues beyond the CMTS.

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All good questions, I'll atempt to ask tomorrow given their backend to test/look is up. 

As for the Smokeping, I am bound to what DSL reports offers. I've been meaning to stand up my own VM to do it locally to the CMTS but im been busy/lazy. But it looks liek these reoccuring issues have forced my hand. 

I'll report back tomorrow and hopefully Dave might have a peek at my modem as well. 

[Snowberrie]

My modem is finally updated to Version 2.0.10.27. Thank you @RogersDave.

However, I am still getting around only 300-500 mbit/s on download even on my ethernet. Would anyone know if it is the area I am living in? I am living near Erindale Park in Mississauga.

[Mythen]

Interesting situation. I attempted to power cycle my modem and now all I get is the power light. Anyone else see this before?

[mrdawgy]

I am having a huge issue i just got the net hooked up and intended to use it for xbox one online gaming but am getting slow speeds and packet loss which is making it impossible to even start games. I switched my modem today the coda 4582 for a new one to try and resolve the problem but it did nothing.

[gp-se]

@mrdawgy

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@mrdawgy wrote:

I am having a huge issue i just got the net hooked up and intended to use it for xbox one online gaming but am getting slow speeds and packet loss which is making it impossible to even start games. I switched my modem today the coda 4582 for a new one to try and resolve the problem but it did nothing.

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Can you log in to the modem, and go to DOCSIS WAN Page and post your signal levels please. 

[gp-se]

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@Mythen wrote:
Interesting situation. I attempted to power cycle my modem and now all I get is the power light. Anyone else see this before?

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@Mythen I would try a factory reset: Use a Pen Tip or similiar object to press and hold the reset button down for 15 seconds then release. If that doesn't help I would suggest going to a Rogers store and swapping the modem.

[mrdawgy]

Downstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Signal noise ratio (dB)
1	591000000	256QAM	4.300	7	38.983
2	567000000	256QAM	3.300	3	38.983
3	573000000	256QAM	3.800	4	38.605
4	579000000	256QAM	3.300	5	38.605
5	585000000	256QAM	4.400	6	38.605
6	561000000	256QAM	3.000	2	38.983
7	597000000	256QAM	4.200	8	38.983
8	603000000	256QAM	3.800	9	38.983
9	609000000	256QAM	4.400	10	38.983
10	615000000	256QAM	3.900	11	38.983
11	621000000	256QAM	3.600	12	38.983
12	633000000	256QAM	4.700	13	38.983
13	639000000	256QAM	5.100	14	38.983
14	645000000	256QAM	5.300	15	40.366
15	651000000	256QAM	5.300	16	40.366
16	657000000	256QAM	5.600	17	38.983
17	663000000	256QAM	5.700	18	38.983
18	669000000	256QAM	5.900	19	38.983
19	675000000	256QAM	5.900	20	38.983
20	681000000	256QAM	5.800	21	38.983
21	687000000	256QAM	5.900	22	38.983
22	693000000	256QAM	5.000	23	38.983
23	699000000	256QAM	5.300	24	38.983
24	705000000	256QAM	5.200	25	38.983
25	711000000	256QAM	5.200	26	38.983
26	717000000	256QAM	4.600	27	38.983
27	723000000	256QAM	4.700	28	38.605
28	825000000	256QAM	3.800	29	38.983
29	831000000	256QAM	4.100	30	38.983
30	837000000	256QAM	4.900	31	38.605
31	843000000	256QAM	5.500	32	38.983
32	555000000	256QAM	3.700	1	38.605

OFDM Downstream Overview

Receiver	FFT type	Subcarr 0 Frequency(MHz)	PLC locked	NCP locked	MDC1 locked	PLC power(dBmv)
0	4K	275600000	YES	YES	YES	4.000000
1	NA	NA	NO	NO	NO	NA

Upstream Overview

Port ID	Frequency (MHz)	Modulation	Signal strength (dBmV)	Channel ID	Bandwidth
1	30596000	ATDMA - 16QAM	40.000	1	6400000
2	38596000	ATDMA - 16QAM	43.000	3	3200000
3	23700000	ATDMA - 16QAM	39.500	2	6400000

OFDM/OFDMA Overview

Channel Index	State	lin Digital Att	Digital Att	BW (sc's*fft)	Report Power	Report Power1_6	FFT Size
0	DISABLED	0.5000	0.0000	0.0000	-inf	-1.0000	4K
1	DISABLED	0.5000	0.0000	0.0000	-inf	-1.0000	4K

[gp-se]

@mrdawgy your signal levels look excellent. I would suggest you send a PM to @CommunityHelps with the subject "CODA Firmware Trial"

include your account number, modem mac address, and modem serial number. You can find those when you log in to the modem. Tell them you would like the beta .27 firmware, with .27 you can disable ipv6, I would disable ipv6 if you are gaming with XBox.

[dallasdinatake]

Are you connect wifi or hard wire

[jgamm]

I've been on 0.27 for almost two weeks now and I still get massive UDP packet loss and fail the dslreports bufferbloat test. When I connect to pia VPN which I'm paying for because of this very problem, I get no packet loss and a stable connection.. but I wish I didn't have to pay a VPN provider 10$ USD per month just for a stable connection...

[Telek]

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@jgamm wrote:
I've been on 0.27 for almost two weeks now and I still get massive UDP packet loss and fail the dslreports bufferbloat test. When I connect to pia VPN which I'm paying for because of this very problem, I get no packet loss and a stable connection.. but I wish I didn't have to pay a VPN provider 10$ USD per month just for a stable connection...

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I'm confused -- a VPN uses your existing connection. How could it possibly provide no packet loss when the underlying connection does?

I understand that it's routing UDP over the TCP based VPN, but is Rogers' routing really that disasterous that there is massive UDP packet loss within the Rogers network itself?

We really need some actual UDP testing setup.

[jgamm]

Basically when I play any games with no VPN connection turned on... I get ping spikes all the way up to 2000 ms +- consistently and without fail. On tracerts I see huge packet loss starting at the first Rogers hop on my connection. When I use private internet access as my VPN pro oder and connect to their Toronto server, I get a rock solid 40ms +- and it's been like that for a few weeks now. Never had a single ping spike nor failed bufferbloat test when I'm connected to the VPN. The downside being I don't usually get my full 100mbps do speed that I pay for.. all around a very dissatisfying experience to say the least

[Telek]

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@jgamm wrote:
Basically when I play any games with no VPN connection turned on... I get ping spikes all the way up to 2000 ms +- consistently and without fail. On tracerts I see huge packet loss starting at the first Rogers hop on my connection. When I use private internet access as my VPN pro oder and connect to their Toronto server, I get a rock solid 40ms +- and it's been like that for a few weeks now. Never had a single ping spike nor failed bufferbloat test when I'm connected to the VPN. The downside being I don't usually get my full 100mbps do speed that I pay for.. all around a very dissatisfying experience to say the least

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So if the VPN connection is severly throttling your connection, that would explain why you don't see bufferbloat, and why you don't see latency spikes. You could probably get the same results by enabling QoS on your computer and/or setting a bandwidth limit in the 50mbit range probably.

The packet loss... I'm not sure about. Doesn't make sense. It's obviously taking a different path over VPN, but ICMP loss via Rogers' network seems highly unlikely as that would be affecting everyone all the time.

[jgamm]

I'm gonna try that when I get home. When I play WoW though and it's the only device using my connection, I get massive lag without the VPN still, and I highly doubt that game on its own puts much strain on my bandwidth.

Edit: In the modem (also using as router) I cannot find a qos menu. Im on 0.27. So is it possible that if I switch to bridge mode and supply my own router I can set QoS and fix this for now at least? Is this a problem with the router hardware itself or if I use another router without qos enabled will I still experience bufferbloat?

[Telek]

@jgamm yeah we don't get QoS on the Rogers' modem. Check your computer though, depending on the network card, some drivers will have some form of QoS.

I'd hold off on buying your own router until we know more about the cause of this.

[Makaveli99]

You need to buy a real router if you want good working QOS.

Anything else will be a waste of time!

Or get a used one and throw Tomato or DD-WRT on it.

Also agreed hold off until more invesigation of the issue is done.

[JohnBeaudin]

@RogersDave

I was wondering if the new firmware will be released soon to BETA testers?

[RyzenFX]

@JohnBeaudin

I'm not really sure when the new firwmare will be released to beta testers, but I'd imagine it'll be in the next 2-3 weeks. 

Given that Rogers should be launching it's next gateway next month I'd assume things are ramping up, so Dave won't have as much time to reply to us. 

[JohnBeaudin]

The new gateway, that looks promising thought!