Hello Vijay Yadav,
Basically the process is below:
First you will need an user account to access the ePO DB from the NSM. Instructions regarding which kind of permission you need to have on the ePO DB are available here:
Then, on the NSM configuration (My Company - Integration - ePolicy Orchestrator - Server Settings) you will need to type the IP address, port and user account of the ePO database server. Also on this screen you will see a link named "ePO Exstension". Click there and download the NSM exstension for ePO, file name is NSPExtension.zip.
Then on the ePO console, go to Server - Extension. Click Install Extension and browse to the file named NSPExtension.zip that you just downloaded from the NSM.
For step by step instructions, take a look on the document named nsp_integration guide_6.0_en.pdf which is attached for your convenience.
Hope this helps.
Let me clarify some things here that I almost forgot :-)
If you are using ISM 4.x, INtrushield Manager will connect directly into your SQL server on SQL port (by default it's 1433).
If you are using NSM 5.x or 6.x, the Network Security manager will connect directly into your ePO HTTPS port, which is by default 8443.
So if you are using ISM 4.x, on the ISM configuration you will need to fill the fields with a SQL account which has permissions in your ePO database.
If you are using NSM 5.x or 6.x, you will need to fill the fields with an ePO user account, it's not a SQL account.