Pyung Dong Cho

Performance evaluation of communications processing module in PSTN access subsystem for interworking with PSDN

In this paper, we provide the communications processing module in the Telephone Network Access Subsystem (TNAS) of the Advanced Communications Processing System (ACPS). We define communication tasks and related resources such as several queues which are executed in real-time operating systems, and we implement the procedures for processing user information. Through traffic modeling and simulation, the performance of the service processing board assembly (SPA) is evaluated in terms of system utilization and buffer size. The ACPS should accommodate various public networks such as the public switched telephone network (PSTN), packet switched data network (PSDN), frame relay network, and asynchronous transfer mode (ATM) network. The communications module proposed in this paper could be used in the interface between the SPA and the high speed network adaptor(HSNA) of other network interface subsystems.

Multimedia data transfer for supporting middleware service

We designed and implemented a peer-to-peer connection oriented mode protocol for multimedia data transfer in developing the Group Communications on Advanced Network (GiANT) application which supports a computer supported cooperative work (CSCW). We describe the Multimedia Communications Forum (MMCF) general reference architecture model and the functions of the transport domain. We also define service primitives, transfer protocols, and the user interface for the peer-to-peer connection oriented mode protocol. We test the protocol operations by transferring digital video data which is a core technical component of multimedia applications in real time. The protocol is operated correctly to establish and release the connection, and to transfer data.

The implementation of a billing data processing mechanism for open access to information services

The billing data processing mechanism in a communication processing system (CPS) provides an information provider (IP) access function and a billing data generating function. To perform this mechanism, the CPS uses an information billing protocol (IBP) which defines the communication procedure between the CPS and IPs and generates the billing information. Using this mechanism, information users can connect open IPs without a service account and the IPs reduce the billing management overload. This paper describes the concept of the IBP, the generation of billing data in the information service access point (ISAP) and management of billing data in mediation-operation, administration and management (M-OAM).

The communication bridge for message handling and protocol conversion services between ISDN and PSDN

This paper proposes the design of the Integrated Service Digital Network (ISDN) Access Subsystem (INAS) in order to provide ISDN subscribers with various information services through the Advanced Communications Processing Systems (ACPS). We designed the functional modules of the INAS which were accommodated by the existing open-structure ACPS. In addition to defining the MAS protocol reference model and the call control procedures for the interface between the MAS and the Packet Network Access Subsystem (PNAS), we designed the transfer service primitives used to deliver the information between the network access subsystems and the switching fabric within the ACPS. Thus, ISDN subscribers have easy access to the information services and business using ISDN in Korea will be more activated.