We recently upgraded to 20 mbps x 2 mbps Time Warner Cable. It came with an Ubee DDW3611 modem, which has 4 ports; not enough for our small office.

We've switched the modem to router mode and plugged it into a brand new 24-port unmanaged gigabit switch (D-Link DGS-1024D), with Cat-5 running to all office machines; three PCs, ten or so Macs, a network printer, two Airports and our LAN based phone system (and the occasional iPhone). I was clocking 5 mbps to 12 mbps throughout the day on my machine, but the switch seems to be bottlenecking, as we're experiencing regular, intermittent Internet outages. When I plug a laptop directly into the modem, though, I'm clocking 21 mbps, so it's not the connection. I can't imagine it's the switch either, as it's a dumb, unmanaged one, which should be more than capable to handle a 20 mbps connection. My guess is it's the router settings in the modem ? But, I obviously have no idea.