First check if you are using any proxy settings in the browser?
(eg. In chrome, Settings>Show advanced settings>Change proxy settings>Connections>LAN settings>Proxy server)
If yes, then go to Eclipse kepler Window menu>Preferences>Network connections>Active Provider (as manual) Ref doc
If possible, can you try separately in Eclipse kepler Eclipse IDE for Java EE Developers | Packages
as per this guide.
Regards,
JK