IBM introduced DB2 Native Encryption with DB2 10.5 FP 5. DB2 Native encryption, encrypt db2 backup image and key database files like tablespace containers, transaction logs, archive logs, load copy data as well as load staging files. In other databases this technology is also referred as TDE (Transparent Data Encryption). TDE or DB2 Native Encryption, encrypt data at rest that is in files and not data in transit or data in use. Even if you have enabled DB2 Native Encryption for your database it will not encrypt table data which user can access using DML statement. It is possible to only encrypt backup of database which is not encrypted.
DB2 Native Encryption License Requirement:
In DB2 10.5 FP 5 and later FP, DB2 Native Encryption is available by default with DB2 Express-C Edition, DB2 Advanced Workgroup Server Edition, DB2 Advanced Enterprise Server Edition, DB2 Developer Edition but for DB2 Express Server Edition, DB2 Workgroup Server Edition, DB2 Enterprise Server Edition you need to purchase and apply additional license of IBM DB2 Encryption Offering to use DB2 Native Encryption. From DB2 11.1 DB2 Native Encryption is enable by default for all edition.