Design Of Electronic Seal System

With the continuous development of network technology and information security technology, together with the increasing speed of the process of informationization, E-government has developed rapidly in China so that in many government agencies paperless office appears, such as, Computerization and network and electronic have been used in drafting, approval and circulation of daily documents. Meanwhile, the Government informationization construction department attaches increasing attention to achieving paperless office and government affairs exchange. Because of a large number of documents are transmitted through network, it has become an urgent problem how to ensure electronic documents true and reliable, content integrity and non-repudiation during the transmission process.Seal is an important symbol of the documents'entry into force. Electronic document sealed with electronic seal and paper documents sealed with physical seal have the same look, the same effectiveness and similar usage. Because of its convenience and assurance of the security of seal process, electronic seal get more and more widely used.Application of electronic seal in China started relatively late. "The People's Republic of China Law on Electronic Signature" has come into force since April 1, 2005, before which electronic signature, for the absence of legal support, didn't have any legal effect and therefore was seldom applied. This law standardizes the electronic signatures, establishes the legal effect of electronic signatures and provides a legal basis for the transmission of documents and important information through network, for which digital transmission of documents in China's e-government activities can be achieved.Together with more emphasis on convenience by simplifying operation, electronic seal can ensure the security of electronic document transmission, which makes electronic seal an inevitable trend to replace the traditional sealThis thesis gives the ideas on how to build a general electronic seal security services platform.Physical seal has particular management and use modes, which is detailedly analyzed in this thesis. The management and use habit of electronic seal system should be closed to that of physical seal, to ensure both convenience and security. Management of electronic seal refers to a series of management such as that on seal application, on seal life cycle, on seal storage media, and on seal holder. Usage of electronic seal requires usage license, sealing and examination.The management and application of electronic seal in local area network and special network are also discussed in this thesis.On the basis of the demand analysis, the writer designs an electronic seal system which integrates management, service and application, and whose structure and function are expounded in this thesis where the data format and application interface related to electronic seal system are also described. The general structure of electronic seal system is composed of three subsystems, that is, electronic seal management subsystem, electronic seal service subsystem and electronic seal application subsystem, which are both independent of each other but also inter-related.Electronic seal management subsystem is a software system which can manage the application, manufacture and abolish of electronic seal and ensures the contents of electronic seal real and effective through technology and management uniformly and effectively, that is, seal pictures must be identical to the real status of their holders. So every electronic seal holder needs to have the corresponding public key certificate. Electronic seal management subsystem is a relatively independent system, applies and manufactures digital certificate for electronic seal holder, provides the seal carrier for electronic seal application subsystem.Electronic seal service subsystem is an optional component, offering supportive service for the applying electronic seal. Electronic seal service subsystem adopts an open-ended concept on design which provides the registry table download service to electronic seal application subsystem through visit the PKI LDAP server.Electronic seal application subsystem refers to variety of application softwares which use electronic seal in electronic documents of different formats. As the document formats are different, the combination of electronic seal and documents is in different ways.Electronic seal application subsystem is the user of electronic seal and certificate supporting such functions as online seal, online certificate examination, the server seal, and seal logging and so on, through interfaces and services provided by electronic seal service subsystem which also enables electronic seal to be used off-line.Electronic seal system has different deployment scenarios in different seal modes. In local seal mode which is relatively simple, those who hold valid seal storage media have access to sealing documents. In server seal mode, which is relatively complex, the server hosts electronic seal, so that only those with authorization have access to sealing documents.In this thesis solutions are proposed on ways and processes of electronic seal application, that is, electronic seal functions are achieved by adding electronic plug-ins in Word and PDF, which are in form of Word Addin and PDF Plugin. In view of the application of web form, electronic seal module is provided in form of ActiveX controls. In embedded applications, the system provides embedded seal application interface/ module, which supports application subsystem to seal and exam onstage or backstage, by providing unified and opening interface.In this thesis external interfaces of electronic seal system are also provided, such interfaces including those used to read electronic seal from USBKEY, to get data from electronic seal, to carry out digital signature, to exam electronic seal validation, to get data on the result of examining electronic seal validation, to exam signature and to get error message.