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Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4
reply to elitefx

Re: 24 by 8 channel bonding modem for atpia

I don't believe DOCSIS 3.0 will ever support more than four bonded return channels the same way it will never support more than 24 forward.


34764170

join:2007-09-06
Etobicoke, ON

Why? Just because the chipsets do not exist now? 32x8 chipsets are in the works by both Intel and Broadcom. That is true about the upstream path, but having a 24 channel capable chipset at least allows for greater than 8 channels to be utilized.



BTC Kevin

join:2011-10-01
Nepean, ON
kudos:1

Real question is how many actually channels does Rogers have delegate for Docsis Internet on each local cable loop.

If they only have 8-256x3-64 on local loop of cable, then who cares about a 24x8 yet. Wouldn't see any benefit.
Now if they had 24-256x8-64 running then of course I'd be buying one.

But until Rogers drops the Analog TV stations to open up some digital channel space, ain't going to happen.



TwiztedZero
Nine Zero Burp Nine Six
Premium
join:2011-03-31
Toronto, ON
kudos:5

They'd also have to install D3.1 line cards on all their HFC equipment. Basically replacing all the D3.0 ones. Not a very cheap thing to do right off.

Anyways all told it'll be a while before we see anything of this nature around our neck of the woods. Lets just wait for the new tech to get ratified first eh?
--

!- From the mind located in the shadows of infinity -!
Nine.Zero.Burp.Nine.Six
Twitter = @TwiztedZero
Chat = irc.teksavvy.ca



Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4
reply to 34764170

said by 34764170:

Why? Just because the chipsets do not exist now? 32x8 chipsets are in the works by both Intel and Broadcom. That is true about the upstream path, but having a 24 channel capable chipset at least allows for greater than 8 channels to be utilized.

24x4 is the most that DOCSIS 3 in its current form. You can run more channels on a node, but it is the most that can be bonded simultaneously. Anything more than that and you're getting into 3.1 transitional stuff.

8 upstream channels is possible if they start to climb into low-band VHF and FM for return channels. As it stands right now, DOCSIS 3.0 doesn't support that beyond a very small extension. 3.1 very well could, I don't know for certain.


Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4
reply to TwiztedZero

said by TwiztedZero:

They'd also have to install D3.1 line cards on all their HFC equipment. Basically replacing all the D3.0 ones. Not a very cheap thing to do right off.

3.1 and 3.0 can't co-exist on the same channels either the same way 1, 2 and 3 can, meaning you'll need an entirely different chunk of spectrum for 3.1 all the while maintaining the existing 1/2/3 spectrum until all your users are migrated over. 3.1 will be more complicated and expensive than the jumps between 1, 2 and 3 were.


TwiztedZero
Nine Zero Burp Nine Six
Premium
join:2011-03-31
Toronto, ON
kudos:5

It was my understanding that 3.1 was backwards compatible with 3.0, was I wrong? I'm talking about the hardware technology not the actual "spectrums".



Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

said by TwiztedZero:

It was my understanding that 3.1 was backwards compatible with 3.0, was I wrong?

Kinda. All 3.1 modems will support 1/2/3 and can be used on existing stuff out there now, but a DOCSIS 3.0 modem can't talk 3.1. This contrasts with a DOCSIS 1.0 or 2.0 modem, which can *still* talk to a DOCSIS 3.0 forward channel and nearly all or (in the case of 2.0) all of the return channel modulations.

34764170

join:2007-09-06
Etobicoke, ON

2 edits
reply to TwiztedZero

said by TwiztedZero:

They'd also have to install D3.1 line cards on all their HFC equipment. Basically replacing all the D3.0 ones. Not a very cheap thing to do right off.

That was implied by what I said. This requires new hardware at both ends.

34764170

join:2007-09-06
Etobicoke, ON
reply to BTC Kevin

said by BTC Kevin:

Real question is how many actually channels does Rogers have delegate for Docsis Internet on each local cable loop.

If they only have 8-256x3-64 on local loop of cable, then who cares about a 24x8 yet. Wouldn't see any benefit.
Now if they had 24-256x8-64 running then of course I'd be buying one.

But until Rogers drops the Analog TV stations to open up some digital channel space, ain't going to happen.

It's not about what they have in the field now but what they can do if the appropriate CPE is rolled out.

Rogers has already dropped analog cable channels in the areas that matter the most for DOCSIS.

34764170

join:2007-09-06
Etobicoke, ON
reply to TwiztedZero

said by TwiztedZero:

It was my understanding that 3.1 was backwards compatible with 3.0, was I wrong? I'm talking about the hardware technology not the actual "spectrums".

Yes, as in the CPE can run in both DOCSIS 3.1 and 3.0 modes. It would be like plugging a VDSL2/ADSL2+ modem into an ADSL2+ DSLAM and expecting it to work in VDSL2 mode. DOCSIS 3.0 and 3.1 utilize different spectrum and co-exist on the same cable plant.

34764170

join:2007-09-06
Etobicoke, ON
reply to Gone

said by Gone:

24x4 is the most that DOCSIS 3 in its current form. You can run more channels on a node, but it is the most that can be bonded simultaneously. Anything more than that and you're getting into 3.1 transitional stuff.

I find that questionable when I can see references to ISPs testing 32 bonded channel setups and CMTS vendors testing CMTS supporting 32 bonded channels. IMO Broadcom and Intel wouldn't bother creating 32x8 chipsets if it wasn't possible to utilize all of the channels. Broadcom has released their new 32x8 chipset and Intel will very soon. I'm not necessarily claiming it'll be possible in the "real world" as all too often test scenario setups are a more ideal environment over the real world setup, but I think it is possible using DOCSIS 3.0 tech.


Teddy Boom
k kudos Received
Premium
join:2007-01-29
Toronto, ON
kudos:20

said by 34764170:

said by Gone:

24x4 is the most that DOCSIS 3 in its current form. You can run more channels on a node, but it is the most that can be bonded simultaneously. Anything more than that and you're getting into 3.1 transitional stuff.

I find that questionable

Indeed. I can't see why there is any limit on the downstream channel bonding at all. Upstream, if you stick with the 42MHz top end, you can argue that there isn't room for a full 8 channels. There is room for 4 wide and 4 narrow though..
--
electronicsguru.ca


Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

said by Teddy Boom:

Indeed. I can't see why there is any limit on the downstream channel bonding at all. Upstream, if you stick with the 42MHz top end, you can argue that there isn't room for a full 8 channels. There is room for 4 wide and 4 narrow though..

This is what I had read with specific reference to the 24 channel limit.

»btreport.net/2013/04/docsis-3-1-···nd-back/

I suppose you could go 32 or more, whatever. Either way, all anyone is doing is tying together at the MAC level what is ultimately the exact same technology we've been using since the 1990s. Something's gotta give, no matter how many channels you bond. That's why 3.1 is 3.1.


BTC Kevin

join:2011-10-01
Nepean, ON
kudos:1
reply to 34764170

said by 34764170:

said by BTC Kevin:

Real question is how many actually channels does Rogers have delegate for Docsis Internet on each local cable loop.

If they only have 8-256x3-64 on local loop of cable, then who cares about a 24x8 yet. Wouldn't see any benefit.
Now if they had 24-256x8-64 running then of course I'd be buying one.

But until Rogers drops the Analog TV stations to open up some digital channel space, ain't going to happen.

It's not about what they have in the field now but what they can do if the appropriate CPE is rolled out.

Rogers has already dropped analog cable channels in the areas that matter the most for DOCSIS.

Rogers still has analog here.

They moved to requiring those cheep little Cisco digital-2-analog box's. And will not sell analog plans. But analog is still live on the line if ya remove the low pass filters they put on it.

34764170

join:2007-09-06
Etobicoke, ON
reply to TwiztedZero

said by TwiztedZero:

They'd also have to install D3.1 line cards on all their HFC equipment. Basically replacing all the D3.0 ones. Not a very cheap thing to do right off.

It would also require replacing the routing engine, WAN backhaul uplinks and other components in the CMTS too further driving up the cost. That is also assuming the CMTS can be upgraded without any capacity constraints in the underlying platform. There are probably CMTS in the field from some vendors that will have to be replaced all together. Just thinking about that makes me see big $$$ in my eyes.

34764170

join:2007-09-06
Etobicoke, ON
reply to Gone

said by Gone:

This is what I had read with specific reference to the 24 channel limit.

"The next step past 24 channels would have involved new ASICs."

Which exist now. Anyway, 3.1 is the ultimate end goal but it is still a long way away. There is still quite a bit of room for growth with 3.0 in the years to go before 3.1 is rolled out. But they'll have to roll out more channels.

34764170

join:2007-09-06
Etobicoke, ON
reply to BTC Kevin

said by BTC Kevin:

Rogers still has analog here.

They moved to requiring those cheep little Cisco digital-2-analog box's. And will not sell analog plans. But analog is still live on the line if ya remove the low pass filters they put on it.

They don't have to get rid of all analog to have some improvement. I'm not expecting the most ideal DOCSIS setup which would be to get rid of even digital and go all IPTV which is what Rogers already has on their roadmap and they'll be very aggressive about implementing. They got rid of some of the lower analog channels to improve the upstream situation and AFAIK they can still increase the number of downstream channels.


Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4
reply to 34764170

You're already using a quarter of an 860MHz plant's capacity at 32 channels. At that point, the cost/benefit ratio between sticking with DOCSIS 3 and extending the plant's capacity to 1GHz or 1.2GHz for additional channels or going full-bore into 3.1 starts to blur.


34764170

join:2007-09-06
Etobicoke, ON

Of course, but you also have to consider what the MSO might want to do relatively soon vs having to wait years to do.



Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

Planning and deploying wide-scale bandwidth expansions to a plant don't happen overnight, either.


34764170

join:2007-09-06
Etobicoke, ON

1 edit

I never claimed it does, but it is at least possible to do so. Carriers want options. Some might choose to do things in the near term and others might want to push things out way into the future. The Canadian carriers in general are more aggressive about cable network upgrades versus the US carriers.


eeeaddict

join:2010-02-14
reply to 34764170

wouldn't GPON be a better investment for any area that requires any significant upgrades?



Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

said by eeeaddict:

wouldn't GPON be a better investment for any area that requires any significant upgrades?

Replacing any sort of existing coax with fibre is an undertaking of epic proportions. Even so, the cable companies in Ontario have more RFoG out there than Bell does GPON. Throwing GPON onto the same fibre as RFoG isn't all too big of a deal for the cable companies if that was the route they wanted to go, but right now they really don't need to.

Fraoch

join:2003-08-01
Cambridge, ON
kudos:2
Reviews:
·TekSavvy Cable
reply to BTC Kevin

Old thread but...

said by BTC Kevin:

But until Rogers drops the Analog TV stations to open up some digital channel space, ain't going to happen.

Rogers is indeed dropping some analog channels and moving them to digital. According to my latest bill, 2 will be dropped on October 1st and 5 more on October 21st.


Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

said by Fraoch:

Rogers is indeed dropping some analog channels and moving them to digital. According to my latest bill, 2 will be dropped on October 1st and 5 more on October 21st.

Cogeco in Hamilton and Halton Region have no analog - period. They are 100% digital systems.

Most of Cogeco's systems have been 80% digital for the last few years as it is, with only 2 through 13 or 2 through 28 being analog.

34764170

join:2007-09-06
Etobicoke, ON
reply to Fraoch

Rogers has dropped analog channels in a lot if not most areas quite awhile ago.



Gone
Premium
join:2011-01-24
Fort Erie, ON
kudos:4

said by 34764170:

Rogers has dropped analog channels in a lot if not most areas quite awhile ago.

Every last one? Not even 2 through 12 analog? I'd like to know what systems those are. I'm curious.

Fraoch

join:2003-08-01
Cambridge, ON
kudos:2
Reviews:
·TekSavvy Cable

I still get channels 2-45 analog. Come October, it will be 2-40.

OT: although Rogers states I can get a "free digital adapter", when I enter my cable number account on their site it states I'm "ineligible"?


34764170

join:2007-09-06
Etobicoke, ON
reply to Gone

Some, not all. AFAIK the focus was on improving the upstream channel configuration first. But they will eventually get rid of all analog all together.