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Dmole

join:2008-07-11
Reviews:
·TekSavvy DSL
·Start Communicat..

1 edit

[Cable] Cable modem - what to buy

Any one know the specifications of the missing information on this chart?:
»internet.wikia.com/wiki/Comparis···e_Modems

(an old related thread: »Re: [Cable] Cable modem - what to buy )

I want to get a modem that is fast and has wide support (incase I want to sell it etc)

Thanks.

[*Edited router modem slip up*]


Scycotic

join:2012-12-10

Note: don't confuse router and modem.

As for a good modem, the DCM476 is pretty popular nowadays...or the SB6120 which has a great reputation.


MrMazda86

join:2013-01-29
Kitchener, ON

+1

I myself have used both modems. There is only one potential "issue" with the firmware to be noted if you are planning on using this modem on the Rogers infrastructure on a TPIA. Some of these modems (such as my Thompson DCM-476) are equipped with an older firmware. In most cases (such as mine), the "older" firmware doesn't cause a problem, however you must be careful to note this if you have a problem that Rogers needs to examine.

I was fortunate in my case when I had an RF signal issue on the line because the TekSavvy rep that I was speaking to actually knew what he was talking about. In cases where problems exist if you have the "older" firmware, Rogers is known for blaming the problem on "unsupported firmware", even when the firmware has nothing to do with the issue. You can find more details on that in this forum thread.

Aside from this "alleged" issue with the firmware, my experience says with either of those modems that the firmware is not an issue. For me, both of those modems (Thompson DCM-476 & Motorola SurfBoard SB6120) both worked flawlessly.



addy

@nltelcom.com
reply to Dmole

The Huawei cable modems are the most compatible across all the internet providers. Distributel for example wont allow anything other than Huawei on their networks for new customers.

Huawei is allowed on Teksavvy and on every other cable internet provider, but likely not as a direct customer of Rogers.

I prefer not to use Huawei because there are legitimate concerns about security for their business networking hardware, that might extend to their retail equipment as well.

The 476 works fine btw, just that it isnt allowed on Distributel. Make sure the STAC firmware is 2.50.00 if you're grabbing one as 2.36 might have issues in some areas.


londoner1

join:2007-04-26
London, ON
Reviews:
·Start Communicat..
·TekSavvy Cable
reply to Dmole

I've been using a 6120 for a couple of years now. Works flawlessly. Am looking for another modem to activate up a buddy....sadly Motorola devices are hard to find in Canada and deals are few and far between.....one thing missing in the chart that would be helpful is the Manufacturer Warranty. Start.ca as an example rents a device for $5 (I'd assume it would be a DOCSIS 3 device if the plan requires it)....Frankly I might be inclined to rent if purchasing is north of $100 (with taxes) and a pathetic 12 month warranty.....



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

said by addy :

The Huawei cable modems are the most compatible across all the internet providers. Distributel for example wont allow anything other than Huawei on their networks for new customers.

I think that is because Distributel insists on selling you a modem when you sign up, and they only sell the one model.
--
electronicsguru.ca

Kewjoe

join:2002-04-14
North York, ON
reply to Dmole

I bought a used/refurb Motorola SB6120 from Teddy Boom for $75. It's been almost a month, works great. He warranties it for 1 year.



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

said by Dmole:

Any one know the specifications of the missing information on this chart?:
»internet.wikia.com/wiki/Comparis···e_Modems

That chart needs a lot of help..

The WAN bandwidth of Docsis 2 is variously 42.88mbit/s, 38mbit/s, or about 35mbit/s depending on how you want to count (that is: absolute maximum including overhead, maximum after overhead, and practical approximation respectively).

For Docsis 3, the WAN bandwidth of the SMCD3GN and the SB612x are the same (all 4 channel modems). Similarly, the WAN bandwidth of the DCM47x, DCW775 and Huawei are the same (all 8 channel modems). The discrepancy in the chart is because different spec sheets are calculating differently.

Anyway, the maximum bandwidth isn't particularly relevant. What we care more about is what speed the cable operator will allow on a given modem. I've heard it said that Rogers cut off speed for Docsis 2 is 15mbit/s. Of course there are no packages at that speed, and Rogers will be allowing TPIA to use D2 modems on all packages upto 32mbit/s until April, so it is pretty confusing.

For the record, some knowledgeable posters here say that modems running up to, or at least near, their full capacity shouldn't really be causing the operators any issues, and imposing a bandwidth limit at below half the theoretical number is misguided.

I seriously doubt the MSRP on the DCM476 is $70. There may be an online dealer selling at that price, but that will be below MSRP for sure. There is no way the MSRP on the DCM425 is as low as $30--Canada Computers sells them at $48.99, and Canada Computers is almost always below MSRP.
(I sell DCM425 for $25 nowadays, but then they aren't new--better than new, but definitely used )

Finally, I'm pretty sure that Teksavvy could start accepting the DCW775 any time they want to. Would be nice if we could have an update on that though (hello TSI-people ).
--
electronicsguru.ca


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

Cut my price to $70, market pressures, sorry you couldn't benefit. And, if I'm involved in the sale of the account, I guarantee the modem for as long as you keep the account active (hence better than new in the comment above ).

(thanks very much for the good words!!)
--
electronicsguru.ca


Dmole

join:2008-07-11
Reviews:
·TekSavvy DSL
·Start Communicat..
reply to Teddy Boom

Thanks for the post Teddy, do you know where to find a spec sheet on the Huawei?

Won't the CPU/firmware choice effect the transfer speed?
I'm assuming not all 4 channel modems are the same because my experience with other hardware (routers) tells me stability and actual throughput varies by model.
the alternative is that modems are built with more quality then routers, but I have also added heat syncs to a DSL modem to stabilize it so I'm kinda doubtful about that.

Anyway you sell the things (right?) so you probably know more about it than I do.

I'll try and update that wiki page to reflect your input but feel free to add to it yourself.



d4m1r

join:2011-08-25
reply to Dmole

Anyone considering Huawei networking equipment, please do your homework first.


Dmole

join:2008-07-11

...The complete lack of Huawei documentation seems like a warning.

so the DCM476 looks like the best choice.


koreyb
Open the Canadian Market NOW

join:2005-01-08
East York, ON
reply to Dmole

At this point, just make sure the modem is a D3 modem... any D2 modem will likely not work on anything but the LITE tiers. Shop around, I got my motorola 6120 way back when in TARGET in the US for 75 bucks


The Mongoose

join:2010-01-05
Toronto, ON
Reviews:
·TekSavvy Cable
reply to Dmole

said by Dmole:

...The complete lack of Huawei documentation seems like a warning.

so the DCM476 looks like the best choice.

Generally speaking, you are least likely to go wrong with the DCM476 or the Motorola 6120/6121. Any of these will work perfectly most of the time.

LINCSAT
Premium
join:2003-06-15
Markham, ON

1 recommendation

reply to Dmole

Click for full size
Just signed up for 28/1 Unlimited and picked up the Motorola SB6121 from TigerDirect.ca, UPS shipped and I got it in 4 days not bad. I read all the reviews and spoke to teksavvy and this was highly recommended.


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

said by Dmole:

Thanks for the post Teddy, do you know where to find a spec sheet on the Huawei?

No idea, I've looked in the past.. Very little information on that modem anywhere. Strange

said by Dmole:

Won't the CPU/firmware choice effect the transfer speed?

Sort of. All modems available are either based on Puma5 CPU (4 channel modems plus the SB6141 at 8 channels) or Broadcom CPU (all other 8 channel modems). So ya, there will be little firmware differences I suppose, but the fundamental abilities are pretty much the same across all models.

Certainly Docsis 2 modems are all about the same, I've used many (TJ715x, DCM425, SB510x, DPC2100).

Anyway, the throughput maximums you are thinking of would be very hard to test, and it wouldn't be that useful anyway. Network conditions dominate any throughput limitation in the modem.
(would be nice to hear about practical experience from people on 150mbit at Rogers, that's the only way we'll confirm my theories or learn anything useful)

I have seen a comment here at DSLr about throughput testing on the LAN side of the SMCD3GN. The results were kind of mediocre to poor

said by Dmole:

the alternative is that modems are built with more quality then routers, but I have also added heat syncs to a DSL modem to stabilize it so I'm kinda doubtful about that.

Well, adding heatsink is more about stability I would think. Clock rate and amount of RAM dictate speed, until it crashes, and then the speed is zero
(of course there is some middle ground--performance degrades before the crash happens, or whatever--but I don't think it is so significant)
--
electronicsguru.ca