A time interval consists of two TimeInstances. Please be aware, that the interval is defined in close-open semantics. This means, that the start time is inclusive and the end time of the interval is exclusive. In mathematical notation, the interval is defined as [start, end).
TimeInstance
[start, end)
Specifying in ISO 8601:
{ "start": "2010-01-01T00:00:00Z", "end": "2011-01-01T00:00:00Z" }
Using the same date as UNIX timestamps in milliseconds:
{ "start": 1262304000000, "end": 1293840000000 }