In this date format \/Date(XXXXXX+XXXX)\/ we have two parts:
We use the default Microsoft .NET JSON serialization engine which emits JSON date as the number of milliseconds elapsed since 01-01-1970 UTC.
A relevant documentation on this can be found from the MSDN site here under section “DateTime Wire Format”.
You can also use XML transport if the JSON format is inconvenient for you. REST/XML returns dates in the format of “CCYY-MM-DDT00:00:00” – e.g. 2016-11-21T00:00:00.