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xymox1
Premium Member
join:2008-05-20
Phoenix, AZ
ARRIS SB8200
MikroTik CCR1036-8G-2S+

xymox1

Premium Member

Re: Upgrade from dpc3000 to dpc3010 and slower upstream speeds

Hmmm......

Further playing. I cant be sure of course until I get my new dpc3010 on monday, but I am starting to suspect that maybe the DPC3000 might be better, at least in my cox cable area using the current Ultimate tier. This might change once they roll out 100Mb tho.

The dpc3010 is a completly different device based on a whole different Broadcom chip set. The ethernet controller ship is built in for example.

Every single chip maker is different in the 3010.

The dpc3000 uses a Texas Instruments chip vs the 3010 which uses a Broadcom.

Even the radio chips are different manufacturers.

So these are very different devices.

The upstream rate I think is cap by the modem itself, which means the chip in the unit has to do some form of rate limiting. This rate limiting might be different between Texas Instruments and Broadcom. In fact the whole way it handles the data stream might be different.

So while the upstream channels are capable of way faster then 5.5Mb/s the cap rate limiting methods might produce different results at these low speeds with different chips.

When I get my new modem, if I verify it does the same 4Mb/s vs 5.5mb/s on the dpc3000 that would be very interesting.

It will also be interesting to see how the SB6180 does on this.
xymox1

xymox1

Premium Member

HMmmmmmmm....

Turns out that Texas Instruments holds a key patent on ACK filtering which has a big effect when a upstream cap is doing rate limiting. So possibly the TI based chips produce better results when rate limiting a upstream channel ?

»www.google.com/patents/U ··· &f=false

Background »www.ti.com/lit/wp/spay01 ··· y014.pdf

Anonguy
@cox.net

Anonguy

Anon

Are you having Cox upgrade the firmware at activation?