Research On Mail Server In UMS

In the past few years,a new messaging system called the UMS (Unified Messaging System) has come into view. The UMS contrasts with the traditional medium-dependant messaging systems,and provides users with an integrated service. As a result,users with different communication terminals can share the same service disregarding the terminal at hand. Messages received from different UMS senders are stored in a unified form (e-mail) and message receivers will be informed as soon as possible according to their service pre-subscribed. For example,the arrival of an e-mail might result in an auto telephone call,either to tell the receiver there is an e-mail for him,or better still translate the text into oral language and read it to the e-mail receiver.Based on the research and implementation on ZHX-UMS,the paper mainly describes the key techniques and typical architectures of UMS. A special emphasis has been given to the UMS Mail server. In the dissertation,detailed discussion on the I/O module of the mail server has been given and some program modules are also provided in order to explain the implementation issues.The ZHX-UMS proposed in the paper has been designed as a three-layer system. The outmost layer (C-layer - Communication layer) deals with I/O issues between the UMS and outside communication world;the inner most layer (K-layer,kernel layer) involves internal management and message storage;while the middle layer (A-layer - Auxiliary layer) plays the go-between function between layers C and K. As the core component in layer K,the UMS mail server is responsible for the storage,transmission and management of the system driven by the layer-K state machine. By comparison with traditional mail servers,it must possess not only more powerful processing and managing capabilities but also the abilities of working with other components of UMS in harmony. Self-implemented mail server provides convenient interfaces for the billing module and other service functions in UMS. So the Mail Server plays a key role in the whole system.Although ZHX-UMS is only a sample system presently and still under improvement,it lays a good foundation for the future implementation.