"With Xbox One you can game offline for up to 24 hours on your primary console, or one hour if you are logged on to a separate console accessing your library," Xbox Wire writes. "Offline gaming is not possible after these prescribed times until you re-establish a connection, but you can still watch live TV and enjoy Blu-ray and DVD movies."
This is the clearest explanation of the Xbox One's internet requirements since Microsoft's reveal on May 21. In a post it removed from Xbox Wire, Microsoft said the console "does not have to be always connected, but Xbox One does require a connection to the Internet."
Microsoft recommends a broadband internet connection of 1.5Mbps for the Xbox One, and suggests mobile broadband for those without access to an Ethernet connection. Xbox One has two wireless antennas, and a gigabit Ethernet port and 802.11n wireless.
"Because every Xbox One owner has a broadband connection, developers can create massive, persistent worlds that evolve even when you're not playing," Xbox Wire says.