Masafumi Katoh

Control architecture for next-generation communication networks based on distributed databases

Intelligent routing control is defined as the process in which the network interrogates the databases containing the relationships between logical numbers, such as personal or information identifiers, and physical addresses in the transport network to find the terminal having the information required to process a user request. The routing control system presented uses distributed databases, each of which manages a switching system and all of which are connected through high-speed signalling networks separate from the transport network. If the requested physical address cannot be found in one database, search requests are distributed at the same time to all other databases. For up to 100 million subscribers, the routing control system can find a physical address within 1 s when each database uses ten memories accessed at 200 ns with an interdatabase linkage speed of 14 Mb/s. >

High-Speed Time Division Switching Technique for Broadband ISDN

A key point in realizing broadband switching networks is architectual efficiency for switching various types of traffic with speeds ranging from several kbits/s to several Mbits/s. We propose a new switching technique, that is, a high-speed time division switching based on the single slot switching technique. This technique has several switching modules corresponding to standardized bit rates of traffic, and each cell is switched in the switching module corresponding to its speed. With this technique, all types of traffic will be equivalent with respect to the grade of service. This paper outlines its principle, clarifies the performance of traffic capacity,and finally proves its feasibility.

Applicability of a layered architecture adopting distributed data processing to M2M communications

We show that a layered architecture distributing M2M application to multiple processing entities in the M2M network is applicable for ubiquitous era. This paper firstly introduces a layered architecture of M2M system, where we put layers for the decomposition of application and the association of de-composited subroutines. Next, we categorize the association of subroutines into two patterns (sequential and random order), and model schemes on state managements (centralization and distribution). Then, we clarify the condition that the performance can be improved by distributed management in terms of processing time for two association patterns. Next, the deployment of de-composited subroutines on processing entities is discussed, where we show basic rules to reduce carried traffic. Finally, we address the requirements of messaging between two processing entities in M2M network to provide QoS such as time limitation.

A strategy of quality control on ATM switching network-quality control path (QCP)

In an ATM network, there are many kinds of calls which require various qualities. A method is required to control the connection and cell administration according to the required quality of service (QoS) for each connection. In this paper, we propose the quality control path (QCP) concept to control the qualities of the established connections in the ATM switch. With this method, the buffers and the capacities of the physical links in the switch are each divided into logical paths. We also described a control scheme to maintain a required QoS for each connection.

The Concept and Model of 4 Dimensional Traffic Engineering

This paper proposes to apply the prediction of coming traffic for routing named 4 dimensional traffic engineering (4D-TE). Current TE can optimize the usage of network resource by dynamic control depending on an instant status of the network, not for long period. The 4D-TE reflects not only current actual traffic but also coming traffic transition, that is, time as fourth dimension is added for an optimum route search. It predicts traffic transition by referring past statistical data and allocates the minimum cost route for coming large traffic. This paper clarifies how much effectiveness we can get by the 4D-TE. Then, this paper describes the required functions such as traffic pattern management, the prediction of traffic transition and optimum route calculation, and shows how to define link cost for route calculation. Finally, concerning the architecture of control plane for the 4D-TE, the performance of hierarchical architecture is modeled and evaluated

Viewing approaches to a large scale Internet backbone with ATM technology

The explosion of the Internet is still continuing due to the expansion of the number of users and multimedia services. To replace the conventional router network, a new paradigm of some multi-layer switching techniques are proposed in the standardization sectors and forums. We estimate the best solution for a very large scale Internet backbone, i.e. a nationwide scale. After estimating the size of the Internet in the future, we study the high speed internetworking solutions. We especially compare the multiprotocol label switching (MPLS) and CL (connectionless)-network from the view point of scalability and the size of the buffers of each node.

Short Paper: Performance evaluation on distributed data process in M2M systems

We show that distributed data processing for M2M applications improves the performance of M2M systems. The important roles of the M2M systems are to associate an application with required data and to execute the application on suitable processing entities for coming ubiquitous environment. First, we show simple rules on deployment of data process to reduce load in underlying M2M network. Next, we clarify cases such that an application should be divided into subroutines for distributed executions. And so, we model centralized and distributed execution as multi-stage queuing system to show the improvement by the distributed execution.

Traffic engineering for IoT

Considering IoT environment, where even network nodes are having not only data transfer function but also data processing function, we are studying which processing entity should execute an IoT application and how to connect the processing entity with terminals requesting the application. Then, we show 4 types of traffic engineering (TE) to minimize delay by the selection of processor and the rearrange of route. Next, we evaluate the complexity of algorithm for each TE type and clarify the effectiveness of each TE in term of the reduction of delay for delay relatively sensitive application. Finally we map IoT applications with adoptable TE types.

Realizing safe and reliable vital sings monitoring with wireless body area networks

In this paper, we report development and performance verification of a wireless body area network prototype compliant with the MAC protocol of the IEEE802.15.6 BAN. The relaying functionality which utilizes a relay between a hub and a node is confirmed when a direct path between them is not available due to shadowing effects. The delay due to switching to the relay topology is less than one second. Also, ID-based frequency channel hopping mechanism is introduced and verified to be able to quickly avoid frequency channel interference among BANs. In addition to that, transmission power control with body movement detection is employed to reduce sporadic disconnection through giving an extra amount of transmission power when the node detects a large fluctuation in received power. With functionalities mentioned above, the prototype is expected to be used for medical monitoring applications where requirements for data delay and disconnection are rather severe.