What kind of system are you using? PC, phone, Mac? What browser?
You can try to traceroute to the server and see where your packets get lost.
Right now I'm seeing some IPv4 traceroute issues with my packets disappearing past the be-12578-pe04.9greatoaks.ca.ibone.comcast.net (220.127.116.11) router, when trying to contact a server on ATT in San Francisco and a Linode server in Fremont. The first symptom was that I couldn't reach Wikipedia because its DNS server wouldn't resolve the name. Because I couldn't reach their DNS server. (I run my own DNS server so I'm not relying on Comcast's cache.)