Presentations

A highly-energy-efficient network using an optical aggregation network and a service cloud has been proposed to reduce the power consumption of today’s Internet greatly. The optical aggregation network connects a solitary giant router to users by logical tree topology. This paper proposes a novel optical aggregation network architecture. The proposed architecture uses 2x2 optical switches and combines the features of a tree topology and a ring topology. The paper also introduces a design method of the proposed network architecture. It is shown that the method can design high-availability and low-optical-loss network with fewer optical switches compared to a duplex tree topology.

This paper focuses on parallel data transmission, which is one of the solutions in considering high-speed transmission in next generation wide area layer-2 network. To realize parallel data transmission, reliable delay and route measuring for every possible path between two nodes and choosing multiple paths with small delay difference is necessary. This paper proposes a new multipath discovery and delay measurement method using bi-directional flooding technique. In the proposed method, extended Ethernet frame and bi-directional flooding technique which runs on data plane is introduced. The computer simulation showed that by applying the proposed bi-directional flooding technique, scalability has been greatly increased.

This paper proposes high energy-efficient IP network architecture with Giant Center Router and Optical Aggregation Network. User IP packets are aggregated and transferred to Giant Center Router through Optical Aggregation Network transparently by dynamic optical resource allocation. Giant Center Router is power scalable with an amount of traffic proportionally. Optical Aggregation network is realized by circuit switches, wavelength converters, and wavelength multiplexers/ demultiplexers. The proposed network scheme reduces the power consumption to 1/20-1/30 compared to the conventional Internet, realizes a network structure well suited to traffic centralization, and offers smooth migration from the conventional Internet.

We have studied a novel optical access network with PLZT (Plomb Lanthanum Zirconate Titanate) optical switches,called ActiON (Active Optical Network), as a next generation access network to replace PON (Passive Optical Network). On the other hand, energy consumption of the present network becomes an important problem today. To resolve this problem, we study an energy efficient metro-access hybrid network by using ActiON. Also, it is necessary to extend a bandwidth capacity of ActiON to realize a scalable network. In this paper, we mainly focus on an energy consumption and a scalability. As a result, the proposed next generation metro-access hybrid scalable network accommodates 600000 users. In the evaluation, we show that proposed network reduces 65 % of energy consumption compare to the present network. Furthermore, blocking ratio of proposed network is lower than a quality assurance of the Internet service in any cases.

Recent years, cloud computing which provides computational resources via Internet is attracting the world. Electricity consumption of data centers increases rapidly because the number of users of data centers increases with the growth of cloud computing. According to the world wide trend which urges growing out of dependence on fossil fuel and nuclear energy, it is hoped to consume electricity effectively and wisely. Then, we propose Live Data Center Migration, which can use electricity wisely because functions of data centers are transferred to other data centers geographically apart. For this proposal, we expand the live migration technology into wide area. This technology is originally used inside a data center, and able to transfer virtual machines from the server to another without stopping processes of the virtual machines. Fig. 1 shows the basic concept of our proposal network. The networks among the data centers are set up over the NGL2 (New Generation Layer 2) network with GMPLS (Generalized Multi-Protocol Label Switching) before the virtual machines migration. During the live migration, the memory images of the virtual machines are transferred via this network. The routes between users and data centers have to be switched smoothly after the virtual machine migration. There are two methods to solve this problem. The first is that, packets arrived at DAT (Dynamic Address Translation) are encapsulated with the header addressed to the data center, and transferred via Internet. The route can be switched due to changing the destination address of capsulation header. The other is that, packets arrived at NGL2 switch are added VLAN (Virtual LAN) tags, and transferred via the NGL2 network. It is necessary to set up VLAN path between users and data centers in advance and the route can be switched due to changing VLAN tag. The proposed system is implemented as shown in Fig.2. In this presentation, we mainly discuss the protocol of how to set up the networks among data centers and how to switch the routes between users and data centers.

We propose a slot-switching based all-optical network to support various network services. Aggregating various types of networks (e.g., access networks for residential users, leased lines for business users, mobile backhauls, and fibre channels for data centers) in a single network is discussed as a candidate of next generation access network. Figure 1 shows the concept of this network. There are virtual OLTs (Optical Line Terminals) in a solitary programmable OLT and each of them provides different services at respective protocols. By integrating network equipments, this network reduces energy consumption drastically. It also facilitates the introduction of new network services which use their own protocols. The simplest way to realize this network is using WDM (Wavelength Division Multiplexing) and allocating each wavelength to each network service. However, this method has low scalability because the number of wavelengths that are able to multiplex in a single fiber is limited. In addition, CAPEX (CAPital EXpenditure) becomes high because it is necessary to develop various types of transceivers that adapt different wavelengths respectively. Our proposed network is an expansion of Active Optical access Network (ActiON) that we have proposed earlier, and uses high-speed optical switches. As shown in Figure 2, this network has capability to transfer any data signal formats transparently in a single wavelength. The bandwidth is shared by all users and dynamically allocated by fixed-length time slots. In this presentation, we mainly discuss the network architecture.

With the advance of the ubiquitous society by shift to IPv6, it is expected that various devices such as cars, home electronics, sensors, tags, and so on will be allocated IP address and connected to the network environment. On the other hand, Cloud computing is attracting the world. Cloud computing, via Internet, provides computation, software, data access, and storage services that do not require end-user knowledge. Then, we have been proposing IP based uGrid (ubiquitous Grid Networking Environment). In uGrid, everything connected to the network is defined as “Service-Part” and assigned IP address. Service-Parts mean not only devices but also software programs and data functions which are virtually “things”. Users can use Service-Parts all over the world. Moreover, by combining various Service-Parts via network, uGrid can provide new mash-up services. Figure 1 shows a concept of IP based uGrid. By connecting several IP addresses, the mash-up service of Service-Parts is realized. Because uGrid manages Service-Parts and executes uGrid service provisioning based on IP address, we utilize the IP mechanism such as routing, signaling, and DNS. The merit of utilizing IP mechanism is that, IP is an originally scalable mechanism, and many sophisticated technologies accumulated for years are available. As a technology to manage Service-Parts with IP addresses, GMPLS is applicable. GMPLS is a suite of protocols which allows automate the provisioning and management of the network. Originally, GMPLS was proposed to generalize MPLS for packet switched network to other networks with different switching capabilities like TDM, lambda, fiber, and so on. Our motivation is to extend this “generalized” from switching capability (network, data link, and physical layer) to Service-Parts (application layer). In this research, extended routing protocol (Service-Routing) and extended signaling protocol (Service-Signaling) are proposed. Service-Routing searches Service-Parts and calculates the route for service mash-up. Service-Signaling executes reservation of Service-Parts resources and the establishment of the connection among Service-Parts. By experiment, it is shown that the combination of Service-Routing and Service-Signaling was succeeded. This technology can realize next generation inter-Cloud which integrates the various Cloud such as SaaS, PaaS and HaaS/IaaS. By interconnecting various IP addresses of services via high-speed and high-capacity optical path, mash-up of service, as if executed in one server without considering the network distance, in cloud network can be realized.

Recently,the power consumption of Internet is increasing rapidly. Thus,we have been proposing an optical aggregation network,which reduces the power consumption of today's Internet greatly. The optical aggregation network connects solitary giant router and thousands of users in transparent 1-hop network. This research proposes new dynamic bandwidth allocation. The propose scheme groups ONUs by considering their distances from OLT (Optical Line Terminal), and calculates their bandwidth allocated to one group while other groups are sending data to OLT. Evaluation shows the proposed scheme achives high bandwidth utilization.

我々は, イーサネットをベースとした新たなレイヤ２プロトコル技術(New Generation Layer-2: NGL2)を提案し, 要素技術の開発及びプロトタイプシステムでの実証実験を進めてきた. 今回, NGL2 over 既存広域イーサネット網実証実験の一環として, 100GbE対応のテラビットLANシステムとの連携実証実験を行った結果を報告する.

This paper reports the demonstration results of the dynamic link power management by energy optimal network topology design with prototype Gigabit layer-2 switches. The result shows dynamic link power management is feasible.

A fast fault recovery method using temporary forwarding of frames has been proposed for wide area layer 2 network with high reliability. In the conventional method, the fault detection nodes forward frames based on pre-established recovery table when a fault occurs. The tables, however, are created without consideration on destination node of path, the frames are dropped before the arrival to the destination node. In this paper, a new fast fault recovery method using k-hop flooding is proposed for decrease in frame losses with no arrival to destination node. The proposed method can decrease frame losses with forwarding from fault detection nodes to all neighbor nodes. By computer simulation, it is shown effective range in proposed method from several perspectives.

We study a novel optical access network with active optical switches, called ActiON (Active Optical Network), as a next generation access network to replace PON (Passive Optical Network). In this paper, we focus on a scalability of ActiON so that it accommodates 600000 users to propose next generation metro-access hybrid scalable network by using PLZT optical wavelength selective switch. In the evaluation, we discuss about energy consumption and blocking ratio. We show that proposed network reduces 65 % of energy consumption compare to the present network. Furthermore, blocking ratio of proposed network is always lower than a quality assurance of the Internet service.

現在のインターネットの消費電力を大幅に削減する手法として, 1台の大容量ルータと数千から数万のユーザを1ホップで接続する光アグリゲーションネットワークが提案されている. 本研究では, 多段に接続した2x2PLZT光スイッチを用い, ツリー型トポロジとリング型トポロジの特徴を組み合わせることにより, 低光損失および高信頼性を満足する全光アグリゲーションネットワークを構築する手法について検討を行った.

With the advance of ubiquitous society including IPv6, it is expected that everything will be connected to the networking environment. Then, a ubiquitous grid networking environment (uGrid) has been proposed. In uGrid, everything from a device to a program is defined as “Service-Part”, and new mash-up services can be provided by connecting several Service-Parts. In this paper, IP Routing/Signaling-based uGrid service provisioning is proposed as a new concept for realizing uGrid. The feature of this concept is to assign IP addresses to Service- Parts and execute uGrid service provisioning in the network layer (IP protocol layer). IP protocol is an originally scalable protocol. Also, many sophisticated technologies accumulated for years can be used in IP protocol. Therefore, by using IP protocol, the construction of scalable and intelligent uGrid is expected. As key techniques, Service Routing and Service Signaling are introduced, and the issues of each technique are listed. By experiment, it was confirmed that the provisioning of a simple video grid service was succeeded by Service Signaling.

With the advance of ubiquitous society including IPv6, it is expected that everything will be connected to the networking environment. Then, a ubiquitous grid networking environment (uGrid) has been proposed. In uGrid, everything from a device to a program is defined as “Service-Part”, and new mash-up services can be provided by connecting several Service-Parts. In this paper, IP Routing/Signaling-based uGrid service provisioning is proposed as a new concept for realizing uGrid. The feature of this concept is to assign IP addresses to Service- Parts and execute uGrid service provisioning in the network layer (IP protocol layer). IP protocol is an originally scalable protocol. Also, many sophisticated technologies accumulated for years can be used in IP protocol. Therefore, by using IP protocol, the construction of scalable and intelligent uGrid is expected. As key techniques, Service Routing and Service Signaling are introduced, and the issues of each technique are listed. By experiment, it was confirmed that the provisioning of a simple video grid service was succeeded by Service Signaling.

We have proposed a novel access network system using ultra-high speed optical switches, called ActiON (Active Optical Network). Compared to PON (Passive Optical Network), which is widely used as an access network today, ActiON can increase the number of subscribers and the transmission distance by applying optical switches. ActiON resolves digital divide issues because it covers mountain areas or highly-populated areas such as China, where are difficult to be supported by PON. In addition, various services are provided to subscribers through optical access networks in recent years, including lifeline services such as a telephone service and mission-critical services such as a business transaction. High reliability is a very important issue for the next generation optical access network, because users of these services suffer a heavy loss when a failure occurs on the network. In this presentation, we focus on improvement of reliability and propose novel protection schemes for ActiON. We show that optical switches enable ActiON to implement redundancy configuration flexibly and realize a cost-effective protection.

With the appearance of the cloud network, high speed data communication among data centers is necessary. However, because the data is transmitted through the Internet, network bandwidth is not enough. To construct large bandwidth WAN at low cost, we propose an Intelligent Cloud Network. In the Intelligent Cloud Network, data delivered with parallel transmission and lower cost private lines that are lower bandwidth are applied as multiple routes. In this paper, we propose parallel transmission system. In this system, parallel routes are set up with GMPLS. The proposed system is implemented on the software switch to evaluate parallel transmission.