I had Comcast installed today after 10+ years of Verizon DSL.
When I ordered service I was told that I would get 20 Mbps down / 4 Mbps up in the performance package.
The tech who installed it said it was only 12 Mbps down in my area.
Some speed tests tonight suggest I am actually seeing ~ 8.7 Mbps sustained download (although surprisingly about 7 Mbps up as well!)
I tested a few sites - and they were pretty much the same - attached tomato and vudu logs from a vudu speed test.
The downstream stats stats from my SB6121 modem
Channel ID 1 2 4 5
Frequency 555000000 Hz 561000000 Hz 573000000 Hz 579000000 Hz
Signal to Noise Ratio 34 dB 35 dB 35 dB 36 dB
Downstream Modulation QAM256 QAM256 QAM256 QAM256
Power Level 1 dBmV 1 dBmV 2 dBmV 2 dBmV
So other considerations.
- My WRT160N modem has 100 Mbps Ethernet port - I don't see why that would be an issue but have seen some reports of SB6121 not playing nicely over a 100 Mbps link
- I see the Zoom 5341J supports 8 download bonded channels vs 4 on the SB6121 - could this make any difference in my speed? I am not even clear if my area supports 8 bonded channels. This thread 'Evidence of 8 Downstream Channel Bonding' »[Signals] Evidence of 8 Downstream Channel Bonding - Post Here
shows my area Santa Cruz - but when I click the link for Santa Cruz it doesn't look as if 8 bonded channels is really supported.
- from the attached tomato logs it looks like I start at ~ 12 Mbps download and then trend to 8.7 Mbps after a few seconds.
So is all this normal. I was expecting 20 Mbps - would be happy with 12 Mbps but seem to be getting ~ 8.7 Mbps. Better than DSL but not Vudu HDX 3 bars or enough for multiple HD streams.
As I say I am new to cable internet - so some ideas or where to look for improvements or how to discuss my situation with Comcast would be appreciated.
EDIT - I should note I usually use OPENDNS servers - have tried both OPENDNS and Comcast DNS servers - doesn't seem to make much difference