干旱区生态环境知识资源中心

Since 2006 among Thai government agencies, official correspondence letters electronic interconnections have been developed under national electronic government interoperability framework or e-GIF. The project involved more than 40 ministerial departments and more than 15 software developers. In the correspondence sending and receiving process, time-stamping and its reliability become significant. In 2001 electronic transaction act was announced promoting digital signature can be legally used in electronic documents. The computer crime act B. E. 2550 requires that servers synchronize with a public time server and maintain precision. The Organization for the Advancement of Structured Information Standards (OASIS) has developed the Digital Signature Services (DSS) standard to let administrators control centralized digital signature systems. In this paper we proposed the development of electronic correspondence letter time-stamping service using the DSS standard.