Takeshi Kawasaki

A study on high speed data communication system using ATM

The authors discuss different ways of offering connectionless service in asynchronous transfer mode (ATM) networks. They examine two alternatives for offering connectionless communication. One is the indirect offering method and the other is the direct method. The layout and configuration of CLSF (connectionless service function) in the network that are required by the direct offering method are examined. An arrangement of CLSF in the network is proposed. The elements of CLSF and the allocation of CLSF functions on the ATM switching system are considered. Based on these discussions, the architecture of the CLSF is proposed using cell-based processing, instead of message-based processing.<<ETX>>

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.

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.

A Method of Introducing Multipath TCP to Mobile Core Networks and Its Evaluations

The number of mobile terminals that have both a cellular interface and a Wi-Fi interface has been growing in the recent years. Meanwhile, Multipath TCP (MPTCP) that enables the simultaneous use of multiple paths with multiple TCP flows while showing just one regular TCP connection with the application has been standardized by the IETF and has drawn more attention recently. One feature of MPTCP is that it can be realized only by operating system layers supporting multipath communication without any modifications of the application. However, it might be difficult to install MPTCP in all server operating systems. In this paper, we propose a method for applying a proxy that forwards TCP communication from a server to MPTCP communication on a mobile core network, and show the results of evaluation with the existing equipment.

Implementation and Analysis of Scalable and Flexible Node for Large-scale Networks

It is necessary to improve the performance of packet forwarding nodes that form part of large-scale and functionally advanced networks to ensure that they function easily and effectively. In this paper, we propose a separation method, in which functions in the network node are divided into forwarding functions and control functions, and each set of functions is executed on different hardware (forwarder and controller). With this method, we configure resources in the forwarder as the controllers own virtual resources. By doing so, the software, which runs on the controller, is able to treat the forwarders resources as its own. We evaluate the effect of this method by applying it to a router, and clarify the performance improvement by the proposed method. And we select a stateful packet filtering as another test target, which executes the complex processing in packet forwarding. We then examine the field where the pro-posed method is effective