The Design And Realization Of The Broadband Access Server Bnas

The future communication network is a high-speed broadband data network, which takes data especially the IP service as its core. Various broadband accessing methods can be deployed in the broadband network construction that includes Asymmetric Digital Subscribe Line (ADSL), Etheraet(LAN), Local Multipoint Distribution System (LMDS), Home Phone line Network Alliance (HomePNA), HFC, etc. This paper is mainly to discuss the application & comparison of various broadband accessing methods and cost analysis. The expanse is the major factor prevents users from accessing broadband. How to access broadband network by sharing or reduce the expanse of broadband accessing is one of the major topics in this paper.Meanwhile, the broadband community network needs the functions of Authentication, Authorization and Accounting multiple protocols (AAA), various charging methods, data flow control, bandwidth management, IP address management, service quality, firewall, Virtual Private Network ( VPN ) and other security mechanisms. All the problems can be settled by accessing the Broadband Network Access Server (BNAS) or the Universal Access Server (UAS) at the edge of backbone network.The detailed features, functions and protocols of BNAS are discussed in this paper. Universal management system is designed for BNAS, includes AAA and user management modules. This paper gives detailed description of the realization and functions of several modules in the system, and specific analysis of the software design of the Remote Authentication Dial In User System (RADIUS) module and billing module.Of course, many problems about community broadband network construction and BNAS need to be settled and improved in the future.