A Time-Division Multiplexed (TDM) Hierarchical Switching System (HSS), proposed by Eng and Acampora [5], provides any size of bandwidth for a number of subscribers by allocating proper number of time-slots in a frame. In this paper, we present a binary time-slot assignment (TSA) algorithm by which a proper size of time-slots in the frame are allocated to each subscriber so as to meet its bandwidth requests. The time complexity of the proposed algorithm is O(NLlog2 L) in which N is the number of input/output links of the central switch and L is the number of time-slots allotted to each link in the frame. As the authors know, the most efficient algorithm proposed in the literature has time complexity of O(min(L, M2)min(N, M)M2), in which M is the number of subscribers that is larger than N in TDM/HSS system. To give a clear idea of relative efficiency between two algorithms, let us give a typical situation of M = L = O(N2). In this configuration our algorithm makes a significant improvement in time complexity by the order of O(M2/log2M).

To provide personal, intelligent, and multimedia services through a mobile communications network, a Mobile Service Control Point (M-SCP) was developed, which performs both the location register and service control functions. The M-SCP was constructed on a common platform to allow quick introduction of new services. Software techniques to reduce the frequency of process-switching, assign the highest priority to real-time tasks, and operate a multiple-CPU structure provide faster real-time processing. This is confirmed by computer simulation and research in the field.

Asynchronous Transfer Mode (ATM) shared buffer switches have numerous advantages, but have the principal disadvantage that all switch traffic must pass through the bottleneck of a single memory. To achieve the most efficient usage of this bottleneck, the shared buffer is made blockable, resulting in a switch architecture that we call "throttled-buffer", which has several advantageous properties. Shared buffer efficiency is maximized while decreasing both capacity and power requirements. Asynchronous operation is possible, whereby peak link data rates are allowed to approach the aggregate switch rate. Multicasting is also efficiently supported. The architecture and operation of this low-cost switch are described in detail.

This letter describes a new input and cross-point buffering matrix switching architecture for high-speed ATM switching systems. The proposed switch has input queuing buffers at each input port, and small size buffers for output port arbitration at each cross-point. These two types of buffers share loads using a simple and high-speed retry algorithm. Hardware size is only half that of conventional cross-point buffering switches. In addition, the switch achieves high-throughput at a condition that the switching speed matches the input and output port speed. This switch is expected to enable the development of high-speed ATM switching systems with each port supporting speeds in excess of 1Gbit/s.

In this paper, the software structure for telecommunication user support are discussed, and it is proposed to apply knowledge processing technology to the software. Capabilities of telecommunications networks are becoming quite complicated, and the number of service items and parameters which have to be selected and memorized will become too large for telecommunications end users to make full use of the network capabilities. As such, more effort should be focused on assisting telecommunications end users to use the network and providing user friendly human interfaces of the network. However, this kind of software has additional type of requirements other than those for protocol handling software and call control software, and the realization of such support software has not yet been fully studied. To realize such support software, this paper stressed the realization of the user-system interface. Especially identified in this paper are meaning-based interpretation of user inputs to permit the handling of synonyms and multivocations, and a method to access the database in the support system without consideration of its data schema. To satisfy these objectives, this paper has proposed that the application data should be represented in both a character string and a meaning representation, and that the thesauruses should have the attribute-value relation. In line with these studies, an experimental system called CAPRIS (CAlling PRocedure Instruction System) was developed. It is used to assist the calling party in a telecommunications network to find an appropriate contact point depending on the purpose of the communication. Implementation of CAPRIS is completed and it was confirmed that all the functions described in this paper were actually realized. Some functional experiments were performed on CAPRIS, and the system was concluded to realize satisfactory user-friendliness.