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In this paper, authors present new schemes of our proposed Global Open Ethernet (GOE) technology from a viewpoint of improving reliability in metro-area Ethernet environment and show the numerical evidence on their performance results. Although several standardized or vendor proprietary technologies are proposed to improve Ethernet reliability, they still have reliability problems in terms of long failure recovery time (due to forwarding database (FDB) flush and recovery from a root bridge failure on spanning tree protocol), broadcast storm, and packet loss in network reconfiguration. To solve these problems, we introduce three schemes, a Per Destination - Multiple Rapid Spanning Tree Protocol (PD-MRSTP), a GOE Virtual Switch Redundancy Protocol (GVSRP), and an In-Service Reconfiguration (ISR) schemes. PD-MRSTP scheme reduces the failure recovery time by eliminating the need to flush the FDB and to recover from root bridge failures. GVSRP scheme ensures the reliability of connections between a GOE domain and a legacy Ethernet domain. Combined with PD-MRSTP, GVSRP prevents broadcast storm problems due to loops in the inter-domain area. ISR scheme enables in-service bridge replacement and upgrade without packet loss. Evaluating our prototype system, we obtained the following remarkable performance results. The GOE network using PD-MRSTP scheme delivered a fast failure recovery performance (4 ms) independent of the number of MAC address entries, whereas the legacy Ethernet network took 522 ms when a bridge had 6000 MAC address entries. Since we found that the failure recovery time increased in proportion to the number of MAC address entries, the one in large carrier network having one million of MAC address entries would take several tens of seconds. Thus using PD-MRSTP can reduce failure recovery time one ten-thousandth comparing with that of legacy Ethernet. In addition, evaluation of the ISR scheme demonstrated that a network can be upgraded with zero packet loss. Therefore, a GOE-based VPN is a promising alternative to other Ethernet VPNs for its reliability and stability.

This paper presents an overview of global open Ethernet (GOE) architecture as a cost-effective Ethernet-based virtual private network (VPN) solution, and discusses a hardware and software implementation of a prototype system. Three main approaches have been proposed for a VPN solution on metro-area network: resilient packet ring, Ethernet over multiprotocol label switching (EoMPLS), virtual bridged local area network-tag stacking (Q-in-Q). None of these schemes can satisfy the following requirements at the same time: network topology flexibility, affordable network functionalities, low equipment cost, and low operational cost. The proposed GOE system is designed to solve VPN management problems of these approaches with MPLS VPN functionality at a low cost of Ethernet-based solution. The key components of GOE are: 1) a novel GOE tag for high-speed switching and 2) a novel routing and protection module via per-destination multiple rapid spanning tree protocol (PD-MRSTP). Via the analytical performance evaluation of EoMPLS, Q-in-Q, and GOE, we show that the memory cost and the network utilization of GOE is two-three times smaller and 22% higher than the other approaches, respectively. We also have developed a GOE prototype system and obtained the following remarkable hardware and software performance results. The GOE core switch delivered 100% of theoretical maximum throughput (10 G) with zero packet loss even with the field programmable gate array platform, and its 10-G port density is 1.5 times denser than the best currently available products. The GOE switch using PD-MRSTP also delivered a significantly fast protection switching time (1.975 ms), which was significantly faster than legacy Ethernet switches. These performance evaluation results prove that the proposed GOE system can be used as a cost-effective high-performance Ethernet-based VPN solution.

The East Japan megaquake left huge impacts to the entire nation. The information and communication technology area is not an exception. The destruction of nuclear power plants by the tsunami led the poverty in electric power, which forced the Japanese people to see energy saving in a new light. The confusion in telecommunication, caused by the destruction of the networks and the congestion of heavy emergency traffic, also amplified the necessity of efficient utilisation of finite radio frequencies. This paper introduces the direction and trends of R&D activities in Japan for saving natural resources such as energy and radio frequency, which are focused more intensively after the disaster. 'Green' activities try to expand their contribution to the telecommunication area. Many smart grid projects have been accelerated and have started field trials. New schemes to share limited frequencies also came into the spotlight. These activities will save natural resources more effectively than ever.

Though the Internet succeeded to converge data and voice networks, it itself is diverging now. The authors believe this derives from two facts; one is the end of universal service era thanks to abundant communication services, and the other the fusion of computers and communications because the speed of networks is catching up that of computer's internal bus. These facts allow us to build networks proprietary for specific purposes such as sensor networks or web services for e-commerce where computer and communication technologies are tightly integrated. As a result, networks are becoming enormously complicated and heterogeneous, and without our effort they will become uncontrollable. The authors believe active network technologies were a good try, but it was not enough. Theories build on solid mathematical basis is indispensable for the analysis of huge systems, and we should try to build such theory. Complex systems theory provides various mathematical formulas such as 'scale-free', and it can be a good starting point. We show as an example that by using selforganization theory ubiquitous networks are considered indispensable for system stability in future business network environment.

The rapid growth of the Internet impacts ATM networks to be furnished with IP handling capability. This paper discusses networking issues for IP and ATM integration. First, it considers function allocation at the boundary of an ATM backbone network and the Internet. As a result, the paper explains the necessity of built-in IP handling capability in an ATM switching system, and summarizes functional requirements for the system architecture. According to the discussion, the authors propose a system architecture for IP/ATM integration in the ATM switching system. The implementation of the proposed architecture is evaluated, and the wire-speed IP handling capability in the ATM switch is confirmed.

The internet protocols, such as TCP/IP, became the de-facto standards. However, some recent communication services require more efficient and lightweight protocols. This paper focuses on the design method to provide cross-layered protocols to satisfy these needs. It is observed that a cross-layer design approach can provide more efficiency at the sacrifice of the layered structure, which may lead complicated interfaces, i.e., ‘spaghettis’, and may cause unexpected bugs. A new design concept for cross-layered protocols is proposed in this paper, which is on a basis of the function pool and scenario table. This concept is applied to near field communication (NFC) protocols to let them get affinity with the internet ones. A series of new NFC protocols are designed and are evaluated with respect to communication quality and throughput. It is confirmed that these protocols have better performance than the original NFC one with less complexity compared to the standardised internet protocols.