Hi Amit,
You could call InvokeServerMethod() to get the server time. That's a simple approach.
However, if you need more secure auditing, this should be done on the server. One way to do this is to implement the IEntityServerFetching interface on the server and log the access to those entities/rows (typically in a separate logging table).
In IEntityServerFetching, you are passed the query, so you can examine it or even execute it in a server-side EntityManager to see which entities will be returned (subject to concurrency conditions), and then add the appropriate records to the audit table. This is a more involved approach, however.