Secure Layer for communication with Type4 Tag

Hi All,

I am new to this NFC technology.

From my side i had completed small application which will write the data like name,mobile-no & amount available in that to the Smart tag of type 4.

I am able to retrieve the written data correctly and able to run the apps successful for Demo.

No i need to handle some security on this like man-in-the-middle,data modification ..etc.

I need your help guys,how and from where to start the security ? ( like provide some secure channel to over come above securities or any other security features you might known very well ).

My final app should handle some security features.

Any sort of help would be appreciable.

Please point me to docs or guide me how & where to start.

Looking forward to head from my forum developers.

Thanks In Advance
Reddy