D-Security(Document Security System, developed by W&Jsoft Inc.) is an endpoint document security system for enterprises. D-Security provides features including, transparent file encryption, permission control, content protection, access log and audit reports. D-Security Viewer is a mobile client for D-Security system. It can communicate with D-Security to access documents file repositories, decrypt the cipher context, display and protect the content of files base on permission control. W&Jsoft Inc., founded in 1996, is a software development company dedicating to provide enterprise document management and protection solutions to customers. There are three major product lines, and they are DMP(Document Management and Protection), D-Security(Document Security) and ADP(Application Document Protection) systems.