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Just upgraded to DOCSIS 3.1 modem, very slow upload speed

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Just upgraded to DOCSIS 3.1 modem, very slow upload speed

Hi, 

 

At the behest of Comcast, I upgraded a fairly new DOCSIS 3.0 modem to the Motorola MB8600 (3.1). Download speed is 175Mbps+, but upload speed is around 1-2Mbps (see test snapshot below). I have tried power cycling the modem and a hard reset (holding the recessed reset button down for 30 secs). 

 

http://speedtest.xfinity.com/results/JGHIJ7SYUNBFX4I

 

I can ping the modem's administrative IP (192.168.100.1), but can't reach the web page - nmap shows tcp/80 and tcp/443 as "open/filtered". I've also tried putting the router on the same subnet (192.168.100.2), but that doesn't seem to work either. 

 

Any ideas? Maybe the CMTS gear needs tweaking? 

Expert

Re: Just upgraded to DOCSIS 3.1 modem, very slow upload speed

Have you tried reaching the admin page with a direct connection to the 8600 (no router in the mix) ?