Hoping someone can help me figure out what I'm missing:
- Web sites slow to load (iMac C2D, 2.8GHz, 4GB RAM, all browsers)
- Cable internet connection speed very fast - i.e. downloads are 300kb-1Mbps, very speedy
- Speed test sites (testmy.net, Speakeasy, Speedtest.net) confirm very fast download speeds
- BUT - same speed test sites totally fail when doing upload tests - the test page hangs without doing the upload
SOLUTIONS I'VE TRIED:
- Turning IPv6 off in Network Prefs
- Turning Firewall off in Security Prefs
- Turning "reject anonymous pings" off in my router (Linksys WRT54G)
- Uninstalling Parallels Desktop (it seemed to add virtual network ports that were always on; they're now gone)
- Rebooting router
- Rebooting cable modem
- Rebooting iMac
- Using OpenDNS for DNS resolution
- Not using OpenDNS
I'm not a system or network admin, but I'm pretty knowledgeable about this stuff, and I'm completely stumped.
In the past, slow DNS resolution has been because of Comcast's servers, and switching to OpenDNS has immediately solved it.
But not this time - it just seems to take too long to initiate downloading from any domain.
I suspect that the sudden inability to do upload speed tests is related to my problem, but I don't know what the actual problem could be.