Hub 3 / Compal CH7465-LG (TG2492LG) and CGNV4 Latency Cause

[Datalink]

Good Day Ladies and Gentlemen,

Greetings from the other side of the pond, so to speak.  Over the last few weeks I've been perusing various user forums across North America and Europe for issues related to Intel Puma 6 modem latency.  Of those forums, your Hub 3 stands out as yet another Puma 6 based modem where users see continuous latency no matter what site is used or what online game is played. Considering all of the problems that are on the go, the following information should be of interest to all Hub 3, Compal CH7465-LG and Hitron CGNV4 modem users.  There is much more to post regarding this, so this is a start, to alert VM users as to the real cause of the latency and hopefully engage the VM engineering staff, via the forum staff, with Arris.  I am surprised to see that there has been no mention on this board of users from other ISPs who are suffering the exact same issues with their modems, so, this may come as a surprise to some, and possibly old news to others.

So, the short story ........

The Hub 3 / Compal CH7465-LG (TG2492LG) & Hiton CGNV4 modems are Intel Puma 6 / 6 Media Gateway (MG) based modems.  These modems exhibit high latency to the modem and high latency thru the modem.  The latency affects all IPV4 and IPV6 protocols, so it will be seen on every internet application and game.  The basic cause is the processing of the data packets thru a CPU software based process instead of thru the hardware processor / accelerator.  It appears that a higher priority task runs periodically, causing the packet processing to halt, and then resume.  This is observed as latency in applications and in ping tests to the modem and beyond.  For the last several weeks, Hitron, along with Intel and Rogers Communications in Canada have been addressing the latency issue within the Hitron CGNxxx series modems.  To date, only the IPV4 ICMP latency has been resolved.  Although this is only one protocol, it does show that a Puma 6MG modem is capable of using the hardware processor / accelerator with good results.  Currently Rogers is waiting for further firmware updates from Hitron which should include an expanded list of resolved protocol latency issues.  For Arris modems, "Netdog" an Arris engineer indicated last week that Arris was onboard to address the issue for the Arris SB6190 modem.  That should be considered as good news for any Arris modem (read Hub 3) user as Arris should be able to port those changes over to other Puma 6/6MG modems fairly quickly.  This is not a trivial exercise and will probably take several weeks to accomplish.  Note that there is no guarantee at this point that it is possible to shift all packet processing to the hardware processor / accelerator without suffering from any packet loss side effects.  Time will tell if all of the technical issues can be resolved with the current hardware included in the Puma 6/6MG chipset.  Last night, Netdog loaded beta firmware on selected test modems on the Comcast Communications network.  As this was only done last night, it's too soon to tell what this version resolves and if it was successful or not.  Netdog has contacts with staff at Comcast, Rogers, Charter and Cox Communications to fan out beta versions and modifications for testing.  I'd say its time to add Virgin Media and/or Liberty Global to that group as well.

Recent activity:

Approx three weeks ago a DSLReports user, xymox1 started a thread where he reported high latency to an Arris SB6190 and illustrated that with numerous MultiPing plots.  This is the same latency that I and other users with Rogers communications have been dealing with for months so it came as no surprise.  As well as reporting via that thread, xymox1 took it upon himself to email several staff members at Arris, Intel, Cablelabs and others.  The result of that campaign was Netdog's announcement, last week, that Arris was fully engaged at resolving the issue.  That has led to last nights release of beta firmware, although as I indicated its too early to determine what the beta firmware resolves, if anything.

The original thread that xymox1 started is here:

https://www.dslreports.com/forum/r31079834-ALL-SB6190-is-a-terrible-modem-Intel-Puma-6-MaxLinear-mis...

Yesterday, DSLReports issued a news story covering the thread:

https://www.dslreports.com/shownews/The-Arris-SB6190-Modem-Puma-6-Chipset-Have-Some-Major-Issues-138...

Today, Arris responded:

https://www.dslreports.com/shownews/Arris-Tells-us-Its-Working-With-Intel-on-SB6190-Puma6-Problems-1...

That response was also picked by Multichannel.com

http://www.multichannel.com/news/distribution/intel-arris-working-firmware-fix-sb6190-modem/409379

This is more news likely to appear in the next few days as additional tech and news staff pick up on this issue.

Hub 3 observations:

Like many others using a Puma 6/6MG modem, Hub 3 users are experiencing latency when they ping the modem, or ping a target outside of the home, game online or use low latency applications.  The common misconception is that this is Buffer Bloat. It's not. Its most likely a case of the packet processing stopping while the CPU processes a higher priority task.  The packet processing is done via the CPU no matter what mode the modem is operating in, modem mode or router mode and no matter what IPV4 or IPV6 protocol is used.  Normally, the latency is just that, latency.  The exception are UDP packets. In this case there is latency and packet loss.  The result of that is delayed and failed DNS lookups, and poor game performance for games that use UDP for player/server comms or player/player comms.

Can this be fixed?

So far, it appears that the answer is yes.  Rogers Communications issued beta firmware to a small group of test modems in October.  This version shifted the IPV4 ICMP processing from the CPU to the hardware processor / accelerator, resulting in greatly improved performance in ping latency.  At the present time we are waiting for the next version firmware which should shift other protocols over to the hardware processor / accelerator.  That can be seen in the following post:

http://communityforums.rogers.com/t5/forums/forumtopicpage/board-id/Getting_connected/message-id/369...

The details and results of last nights beta release to the Comcast group have yet to be seen.

At this point there is enough reading to keep most staff and users busy.  My intention is to post some of the history leading up to this point and instructions on how to detect the latency and packet loss.  This is not thru the use of a BQM.  I had hoped to post this all at once but events are moving much faster than I had thought they would.  For now this should suffice to get the ball rolling.

Below is a link to a post with a couple of HrPing plots from my 32 channel modem to the connected CMTS.  This shows the latency that is observed and reflects what others have posted in this forum using Pingplotter and HrPing.

https://www.dslreports.com/forum/r31106550-

HrPing is one of the freebie applications that can be used to monitor the latency to and thru the modem. 

Pingplots with Pingplotter which show the latency from my modem to the CMTS can be found in the first two to three rows of my online image library at Rogers Communications, located below.  They are essentially what the BQM would look like if you were able to zoom into the plot to the point where you could see the individual ping spikes.  Those ping spikes are common to Puma 6 and Puma 6MG modems.

http://communityforums.rogers.com/t5/media/gallerypage/user-id/829158

 [MOD EDIT: Subject heading changed to assist community]

[nallar]

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@shanematthews wrote:

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@Anonymous wrote:

People need to start contacting their elected MP's over this to try and force VM into putting more resources into resolving this, and who knows - they might decide legislation might be needed to force companies to act more promptly as some companies are supplying hardware to their customer which they have no choice but to use - that is underperforming, not to mention - could in essence be a 'national security issue' because who knows who is using this faulty hardware? Many 'organisations' as well as private consumers? Unfortunately, I cannot go back to a 2AC because of the DHCP bug with it which completely resets the DOCSIS lock when it encounters a DHCP misconfiguration so I am stuck with this SH3. At the end of the day, I would rather have a stable (ish) modem (SH3) then one that cuts out every couple of days (2AC). I am a gamer/streamer too and demand the highest performance so I know how everyone feels about this but I feel totally helpless now, apart from having to contact my MP - who has helped me before with dealing with VM, yet again over the never ending issues with this service.

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No amount of resources from VM can fix this as the issue is caused by Intel not VM, so putting pressure on VM won't actually do anything at all as they cannot fix the issue, as i've mentioned above the likely fix is going to be a hub4 without the puma6 chipset, but thats going to take time to develop and roll out to customers, i wouldn't expect a fix anytime soon unless intel somehow have a breakthrough and find a fix for what is likely a hardware design flaw that cannot be entirely fixed by a firmware update, so by all means waste your MP's time on an issue that cannot actually be fixed by VM at this point

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VM can fix the issue by providing alternate hardware. As an interim measure they should allow customers reporting this fault to activate their own docsis modems with virgin.

VM deserve to have pressure put on them for failing to do anything other than state that a possible firmware update will happen in the future, leaving their users renting modems which don't work.

[itinfocus]

Whilst I understand your position on Virgins inability to unilaterally resolve this issue. The result should not be that Virgin users cut out all of the middle men and gripe directly to Intel.

As you say Intel will have no interest in even fielding these queries.

The only option we have is to raise the issue with our supplier Virgin. Who in turn can put pressure on the OEM Arris. Who can then ultimately bring pressure to bear on Intel.

The more Virgin customer complaints are raised can only be beneficial in keeping up the pressure.

If nobody complains to Virgin they can reasonably say that the issue is low priority as they are not getting any customer push back.

[boltedenergy]

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@itinfocus wrote:
Whilst I understand your position on Virgins inability to unilaterally resolve this issue. The result should not be that Virgin users cut out all of the middle men and gripe directly to Intel.

As you say Intel will have no interest in even fielding these queries.

The only option we have is to raise the issue with our supplier Virgin. Who in turn can put pressure on the OEM Arris. Who can then ultimately bring pressure to bear on Intel.

The more Virgin customer complaints are raised can only be beneficial in keeping up the pressure.

If nobody complains to Virgin they can reasonably say that the issue is low priority as they are not getting and customer push back.

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The fact there is a serious DOS vulnerability in the SH3 modems should now put this higher in their priority list, you would hope... 😛

[itinfocus]

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@boltedenergy wrote:

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The fact there is a serious DOS vulnerability in the SH3 modems should now put this higher in their priority list, you would hope... 😛

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Wouldn't put any money on that 

I'm genuinely curious how Virgin would respond a a DoS attack at the moment. As they allegedly have no stock of Broadcom based modems and the chances of a quick fix are remote.

Looks like a ripe target for an ISP level ransomware attack.

[shanematthews]

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@nallar wrote:

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@shanematthews wrote:

---

@Anonymous wrote:

People need to start contacting their elected MP's over this to try and force VM into putting more resources into resolving this, and who knows - they might decide legislation might be needed to force companies to act more promptly as some companies are supplying hardware to their customer which they have no choice but to use - that is underperforming, not to mention - could in essence be a 'national security issue' because who knows who is using this faulty hardware? Many 'organisations' as well as private consumers? Unfortunately, I cannot go back to a 2AC because of the DHCP bug with it which completely resets the DOCSIS lock when it encounters a DHCP misconfiguration so I am stuck with this SH3. At the end of the day, I would rather have a stable (ish) modem (SH3) then one that cuts out every couple of days (2AC). I am a gamer/streamer too and demand the highest performance so I know how everyone feels about this but I feel totally helpless now, apart from having to contact my MP - who has helped me before with dealing with VM, yet again over the never ending issues with this service.

---

No amount of resources from VM can fix this as the issue is caused by Intel not VM, so putting pressure on VM won't actually do anything at all as they cannot fix the issue, as i've mentioned above the likely fix is going to be a hub4 without the puma6 chipset, but thats going to take time to develop and roll out to customers, i wouldn't expect a fix anytime soon unless intel somehow have a breakthrough and find a fix for what is likely a hardware design flaw that cannot be entirely fixed by a firmware update, so by all means waste your MP's time on an issue that cannot actually be fixed by VM at this point

---

VM can fix the issue by providing alternate hardware. As an interim measure they should allow customers reporting this fault to activate their own docsis modems with virgin.

VM deserve to have pressure put on them for failing to do anything other than state that a possible firmware update will happen in the future, leaving their users renting modems which don't work.

---

They won't allow unauthorised hardware on their network, pretty much end of discussion on that one, so applying pressure won't help in the least

Alternative hardware takes time to rebadge, test, order and deploy, so there isn't going to be an overnight fix for any of these issues

[boltedenergy]

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@shanematthews wrote:

---

@nallar wrote:

---

@shanematthews wrote:

---

@Anonymous wrote:

People need to start contacting their elected MP's over this to try and force VM into putting more resources into resolving this, and who knows - they might decide legislation might be needed to force companies to act more promptly as some companies are supplying hardware to their customer which they have no choice but to use - that is underperforming, not to mention - could in essence be a 'national security issue' because who knows who is using this faulty hardware? Many 'organisations' as well as private consumers? Unfortunately, I cannot go back to a 2AC because of the DHCP bug with it which completely resets the DOCSIS lock when it encounters a DHCP misconfiguration so I am stuck with this SH3. At the end of the day, I would rather have a stable (ish) modem (SH3) then one that cuts out every couple of days (2AC). I am a gamer/streamer too and demand the highest performance so I know how everyone feels about this but I feel totally helpless now, apart from having to contact my MP - who has helped me before with dealing with VM, yet again over the never ending issues with this service.

---

No amount of resources from VM can fix this as the issue is caused by Intel not VM, so putting pressure on VM won't actually do anything at all as they cannot fix the issue, as i've mentioned above the likely fix is going to be a hub4 without the puma6 chipset, but thats going to take time to develop and roll out to customers, i wouldn't expect a fix anytime soon unless intel somehow have a breakthrough and find a fix for what is likely a hardware design flaw that cannot be entirely fixed by a firmware update, so by all means waste your MP's time on an issue that cannot actually be fixed by VM at this point

---

VM can fix the issue by providing alternate hardware. As an interim measure they should allow customers reporting this fault to activate their own docsis modems with virgin.

VM deserve to have pressure put on them for failing to do anything other than state that a possible firmware update will happen in the future, leaving their users renting modems which don't work.

---

They won't allow unauthorised hardware on their network, pretty much end of discussion on that one, so applying pressure won't help in the least

Alternative hardware takes time to rebadge, test, order and deploy, so there isn't going to be an overnight fix for any of these issues

---

is your general strategy for tackling issues to put your hands up and say nothing can be done so lets not bother doing anything?

[shanematthews]

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@boltedenergy wrote:

---

@shanematthews wrote:

---

@nallar wrote:

---

@shanematthews wrote:

---

@Anonymous wrote:

People need to start contacting their elected MP's over this to try and force VM into putting more resources into resolving this, and who knows - they might decide legislation might be needed to force companies to act more promptly as some companies are supplying hardware to their customer which they have no choice but to use - that is underperforming, not to mention - could in essence be a 'national security issue' because who knows who is using this faulty hardware? Many 'organisations' as well as private consumers? Unfortunately, I cannot go back to a 2AC because of the DHCP bug with it which completely resets the DOCSIS lock when it encounters a DHCP misconfiguration so I am stuck with this SH3. At the end of the day, I would rather have a stable (ish) modem (SH3) then one that cuts out every couple of days (2AC). I am a gamer/streamer too and demand the highest performance so I know how everyone feels about this but I feel totally helpless now, apart from having to contact my MP - who has helped me before with dealing with VM, yet again over the never ending issues with this service.

---

No amount of resources from VM can fix this as the issue is caused by Intel not VM, so putting pressure on VM won't actually do anything at all as they cannot fix the issue, as i've mentioned above the likely fix is going to be a hub4 without the puma6 chipset, but thats going to take time to develop and roll out to customers, i wouldn't expect a fix anytime soon unless intel somehow have a breakthrough and find a fix for what is likely a hardware design flaw that cannot be entirely fixed by a firmware update, so by all means waste your MP's time on an issue that cannot actually be fixed by VM at this point

---

VM can fix the issue by providing alternate hardware. As an interim measure they should allow customers reporting this fault to activate their own docsis modems with virgin.

VM deserve to have pressure put on them for failing to do anything other than state that a possible firmware update will happen in the future, leaving their users renting modems which don't work.

---

They won't allow unauthorised hardware on their network, pretty much end of discussion on that one, so applying pressure won't help in the least

Alternative hardware takes time to rebadge, test, order and deploy, so there isn't going to be an overnight fix for any of these issues

---

is your general strategy for tackling issues to put your hands up and say nothing can be done so lets not bother doing anything?

---

Hardly, i'm just being the realistic voice here, its all well and good stamping feet and pointing fingers, that doesn't get results, VM can't fix the hub3 without a fix from intel, however much we hate that fact it doesn't change that its true, VM could never put pressure on intel, the companies aren't even in the same playground, the easier solution is to replace the hardware, however, this still requires them to go through the partner selection process, decide on a suitable base unit, customise the unit to work with the VM network, including rebranding, removal of features VM doesn't want, then they need to test the unit internally, then with a group trial and then they can look at ordering in enough units to meet demand and to launch the campaign for the hub4

This however, as i'm sure you can deduce, will take a fair amount of time and you REALLY do not want them cutting corners to try and appease some random MP you got involved because we'll end up back where we started with another unit that wasn't properly tested and was hastily deployed likely causing more issues than it solves, yes you have all the rights to complain to VM, who knows, they might even offer you a goodwill gesture or some sort of discount, but at the end of the day they can't fix this issue anytime soon and the best thing we can do is not harass them too much, things like this thread should stay here ofc mostly to warn new joiners or people looking to upgrade, outside of that its a waiting game

[nallar]

US cable companies usually have a list of approved modems and allow the usage of any of them.

They should adopt that approach to keep "power users" happy.

Another article popped up:

http://www.techradar.com/news/virgin-medias-super-hub-3-allegedly-has-another-flaw-and-its-a-big-one

[RockerSBM]

HI NALLAR

I too wanting to use My own modem I'm wanting to import a netgear CM1000 to use on the vm network.

I'm going to Be emailing one of the ceo about to to try and get them to do it.

Cheers
Shaun

[nallar]

Good luck!