So you have a number of options in regards to reporting on calls.
Not sure what Shafaquat is referring to. Reporting is completely customizable if you create your own SQL queries and reports. You really have three options.
A) There is some limited canned reporting available with OCS R2 that is set to expand with 14. When you deploy the OCS Monitoring server there is an option to deploy these reports to an SQL reporting server:
This is a good blog describing some of the available options:
B) Create your own SQL queries and reports. The CDR/Monitoring database is nothing more than a SQL database that is easily accessible
Blog on creating custom queries
CDR and Monitoring database scheme
QoE query samples
C)Buy reporting capabilities from a company like Unify2 or Time billing by Convergent Solution
Wave 14 there are going to be a bunch of new partners developing billing solutions and other reporting capabilities
Here is a thread on Technet about some different billing options
Lots of options I hope this helps.
I tried to fill in all the options I could think of but I probably missed a bunch. If you have some good refference for OCS reporting please feel free to post a link in the comments of this post.