Measuring DB time of application using SQL Server Profiler
On server side trace DURATION is the total execution time (in ms) of a query. CPU column will provide you time on CPU (total of one or multiple CPUs). While DURATION - CPU = IO Time

So If RPC-Completed time for single procedure call or total time is according to benchmarks then problem could be on network side.

Where is actual problem. To get this you must keep close eye on Wait Statistics. Which will help you to detect real problem whether its on database side or network.

Note: 
1-In case of parallelism (a query resolved by multiple CPUs) DURATION could be less then CPU. 
2-Profiler will show you DURATION in milliseconds while inserting same trace data in a table, you will get DURATION  in microseconds.