I found a work around. I had an old router laying around from before I had comcast. So I plugged it in to my comcast modem/router, and my desktop likes that network well enough. Not the coolest solution, but it works just fine.
I'm running Ubuntu 14.04 on a Lenovo desktop. Internet used to work fine on it. We got a new cable modem from Comcast, and now I'm having issues with my network connection.
My computer has a connection. ifconfig gives me this for wlan0:
wlan0 Link encap:Ethernet HWaddr 18:cf:5e:03:98:85
inet addr:10.0.0.18 Bcast:10.0.0.255 Mask:255.255.255.0
inet6 addr: 2601:1:8780:39bd:6098:c36d:54fa:af47/64 Scope:Global
inet6 addr: fe80::1acf:5eff:fe03:9885/64 Scope/Link
inet6 addr: 2601:1:8780:39bd:1acf:5eff:fe03:9885/64 Scope:Global
UP BROADCAST RUNNING MULTICAST MTU:1500 METRIC:1
RX packets:75821 errors:0 dropped:0 overruns:0 frame:3479897
TX packets:37624 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:27066662 (27.0 MB) TX bytes:4137161 (4.1 MB)
Interrupt:17
I've pinged www.google.com, www.msn.com, as well as my default gateway 10.0.0.1, usually with 100% success.
I also changed the DNS server to be 8.8.8.8, and made my IP static. The modem and my desktop have been restarted many times
However, 99% of the time, if I try to access a webpage, the browser just hangs while it's trying to connect. Occasionally, I'll get a brief window where I can browse normally for maybe 30-60 seconds.
lspci says my wireless adapter is a Broadcom BCM4352 802.11ac Wireless network adapter
Thanks in advance
I disabled ipv6 on my machine like user68186 suggested. Did not resolve the problem though. And according to this faq: http://www.comcast6.net/index.php?option=com_content&view=article&id=45 ipv6 cannot be disabled on a comcast modem/router.
