IPv6 required for higher Comcast speeds?
A recent ... problem ... with Comcast required me to ditch my trusty SB6121 for a newer SB8200, complete with DOCSIS 3.1. After some griping, due to the aforementioned problem, they offered to double my download speeds from 150 Mbps to 300 Mbps.
However, try as I might, I can't get those speeds from my PC while going through my router (Buffalo WZR-HP-AG300H, running DD-WRT). It's a gigabit router, so there shouldn't be any problem, right? No matter what, I still get right around 150/30.
Well, troubleshooting step #1, I hook up my wife's laptop directly to the modem and run the speed test. I get 360/30. I notice, however, that Comcast's speedtest site has a little icon labeled "Protocol: IPv6," and sure enough, ipconfig shows that the laptop was assigned an IPv6 address. Checking the router settings, it's got an IPv4 IP, and that's what's showing up when I do a speed test.
I've tried getting my router to grab an IPv6 IP from Comcast, but apparently IPv6 support is ... not great. I either get no connectivity, or I get an IPv4 and an IPv6 IP, and when I run a speed test, the site shows that I'm using IPv4. But IPv4 shouldn't limit me from getting higher speeds, should it? My router is definitely a few years old now... could that be a bottleneck? It's supposed to have gigabit ethernet, which should handle 300 Mbit just fine, right?
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