Patent ID: 7958240
Filing Date: 2011-06-07
Classification: H04L,H04W

Abstract:
1. A group judgment device that is connected to a network, comprising: a content request reception unit operable to receive a content distribution request, which is a request to distribute content, from a target device connected to the network; a target time obtaining unit operable to, when the content request reception unit has received the content distribution request, obtain, as a target time, a time required between (a) transmission of first data with a predetermined format to the target device and (b) reception of second data with the predetermined format from the target device, the second data being in response to the first data; a judgment unit operable to (i) compare the target time with a reference time, the reference time being a time required between (a) transmission of the first data to a device belonging to a predetermined group and (b) reception of the second data from the device belonging to the group, the second data being in response to the first data, and (ii) judge that the target device belongs to the group when a difference between the target time and the reference time is within a predetermined range, and judge that the target device is external to the group when the difference is not within the predetermined range, the group being made up of one or more devices that are permitted to share the content; and a content distribution unit operable to distribute the content to the target device when the judgment unit judges that the target device belongs to the group.