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ericn32
meh
Premium Member
join:2009-09-23
Costa Mesa, CA

ericn32 to shade45

Premium Member

to shade45

Re: [TWC] RR Standard with Motorola SB6141 Speed Increase?

By the way, there's a new discussion about the Modem Fee going up to $3.95 per month. I've been eyeing the SB6141, and expect a 25-month ROI.
About the increased speed - here's how it works (correct me if I'm wrong).
Each cable channel gives you about 38 Mbps, and when you're tuned to one channel that's almost fully used, and another has open capacity, the modem has to tune to the other channel to use the available bandwidth. With DOCSIS 3.0, you can tune to 8 channels at once and get bandwidth from all of them, up to your 10 Mbps cap. I imagine that this would deliver more consistent bandwidth.
Also, you might not need the SB6141. It bonds up to 8 channels, giving you about 300 Mbps throughput. The SB6121 bonds 4, giving you about 150 throughput. If you don't think you'll ever want more than 150 Mbps during the life of the router, you just need the SB6121, which retails for $80 on Amazon.
You could also get a DOCSIS 2.0 modem, which are cheaper and most similar to the DCM425 and won't perform any better/worse, just make sure to get one that's DOCSIS 2.0+IPv6 certified. Now would be a bad time to invest in IPv4 equipment.

motorola870
join:2008-12-07
Arlington, TX

motorola870

Member

said by ericn32:

By the way, there's a new discussion about the Modem Fee going up to $3.95 per month. I've been eyeing the SB6141, and expect a 25-month ROI.
About the increased speed - here's how it works (correct me if I'm wrong).
Each cable channel gives you about 38 Mbps, and when you're tuned to one channel that's almost fully used, and another has open capacity, the modem has to tune to the other channel to use the available bandwidth. With DOCSIS 3.0, you can tune to 8 channels at once and get bandwidth from all of them, up to your 10 Mbps cap. I imagine that this would deliver more consistent bandwidth.
Also, you might not need the SB6141. It bonds up to 8 channels, giving you about 300 Mbps throughput. The SB6121 bonds 4, giving you about 150 throughput. If you don't think you'll ever want more than 150 Mbps during the life of the router, you just need the SB6121, which retails for $80 on Amazon.
You could also get a DOCSIS 2.0 modem, which are cheaper and most similar to the DCM425 and won't perform any better/worse, just make sure to get one that's DOCSIS 2.0+IPv6 certified. Now would be a bad time to invest in IPv4 equipment.

actually I would not recommend getting a DOCSIS 2.0 modem simply because they will probably EOL'd by the end of 2013 or 2014 the way things are going. TWC in Dallas already has bonding on the upstreams we are the third or fourth cluster to get upstream bonding behind NY, and Hawaii.

I am betting an upstream speed increase is in my future soon now that I am bonding four upstreams.

mackey
Premium Member
join:2007-08-20

mackey to ericn32

Premium Member

to ericn32
said by ericn32:

Also, you might not need the SB6141. It bonds up to 8 channels, giving you about 300 Mbps throughput. The SB6121 bonds 4, giving you about 150 throughput. If you don't think you'll ever want more than 150 Mbps during the life of the router, you just need the SB6121, which retails for $80 on Amazon.

Sorry, the SB6121 is NOT approved by TWC. People have reported here that they were able to talk TWC into provisioning it for the Standard tier, but TWC will NOT provision it for use with the Extreme (30) or Ultimate (50) tiers. Either save your money and get a cheap D2 modem, or spend the extra $20 and get the approved SB6141.

/M

swintec
Premium Member
join:2003-12-19
Alfred, ME

swintec

Premium Member

said by mackey:

Sorry, the SB6121 is NOT approved by TWC.

Which is odd to me since both the 6121 and the 6141 use the same software versions, one would expect they would both run the same on the network. This is eventually what has allowed comcast users to start owning the 6141, since that model was never on their allowed list.

mackey
Premium Member
join:2007-08-20

mackey

Premium Member

said by swintec:

said by mackey:

Sorry, the SB6121 is NOT approved by TWC.

Which is odd to me since both the 6121 and the 6141 use the same software versions, one would expect they would both run the same on the network.

Are you sure about that? My (limited) research shows the 6121 uses a Broadcom chip whereas the 6120 and 6141 use a TI chip.

As far as TWC not approving the 6120 and 6121, I'm assuming it's an administrative prohibition. Even though it does bonding, it only bonds 4 channels. With 38 Mbps channels, someone on the Ultimate (50) tier will be using almost 50% of all 4 channels by themselves. That's not gonna play nice with D2 equipment also trying to use those channels!

/M

swintec
Premium Member
join:2003-12-19
Alfred, ME

swintec

Premium Member

said by mackey:

Are you sure about that? My (limited) research shows the 6121 uses a Broadcom chip whereas the 6120 and 6141 use a TI chip.

»www.motorola.com/staticf ··· S-EN.pdf

From the 2nd page:
"Benefits:
Easily add the SB6141
to a deployed family of
SB6120s and SB6121s,
all three models utilize
the same firmware
image. This reduces
qualification time
for an Operator and
eliminates configuration
management headaches."