Kanada's papers

Kanada, Y., Ikezawa, M., Miyake, S., and Atarashi, Y., draft-kanada-diffserv-qospifmib-00.txt, Internet Draft, November 1999.

[ 日本語のページ ]
[ Local textual version ] [ Slides used in 46th IETF: Configuration Management BOF, Diffserv WG, and RAP WG (not recommended) ]

Abstract: This document describes a QoS PIF MIB (Quality-of-Service Programming-Interface Management-Information-Base) to be used as an SNMP-based programming interface for routers. This MIB is intended to be a programming interface for router QoS functions, especially DiffServ-related [RFC2475] functions including packet scheduling (queuing), dropping, and metering that must be modular and concisely described. Traffic-conditioning rules and metering rules for DiffServ-related functions are defined modularly by using "virtual flow labels" and exclusive conditions in rules, and new classifications for packet-scheduling and packet-dropping functions are introduced. This document focuses on satisfying the requirements on programming interfaces or programming languages for router control. Thus, the focus is different from that of DiffServ MIB [DSMIB] or QoS PIB [QoSPIB].

Introduction to this research theme: Policy-based Networking

Kanada, Y., IEICE Networking Architecture Workshop 10th Annual Workshop, pp. 106-113, IEICE, 2000.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file in Japanese ] [ OHP PDF file in English ]

Abstract: To realize internet-protocol-based QoS-assured networks, using differentiated services under policy-based networking is a promising approach. A QoS policy server must work in multi-vendor environment. To use standard protocol, such as COPS or SNMP, between the policy server and routers is not sufficient, but also to define and to standardize high-level syntax and semantics, i.e., a language, is required for interoperability. This paper describes the outline of a rule-based language for this purpose. Policy rules can be defined in the policy server and can be deployed to routers or router proxies using this language through an appropriate protocol such as COPS, SNMP, or IIOP. The language consists of several types of rules, i.e., matching, policing (or metering), marking, discarding, and scheduling types, and linkage labels that connects rules. A MIB and/or PIB that simulates the language is also explained in this paper. The language will be implemented in near future.

Introduction to this research theme: Policy-based Networking

Kanada, Y., International Workshop on Quality of Service 2000 (IWQoS 2000), pp. 161-163, June 2000.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]
[ IEEExplore Paper page ]

Abstract: Network node functions, such as QoS or the security functions of routers, are becoming increasingly complex, so programs, not only configuration parameters, are required to control network nodes. In a policy-based network, a policy is defined at a policy server as a set of rules that deployed at network nodes where it must be translated into an executable program or parameters. Thus, a policy must be represented by a form in which the syntax and semantics are clearly defined, and which can be mechanically translated into an executable program. This is possible if the policy is written in an appropriate rule-based programming language. This paper describes such a language in which functions required for DiffServ can be specified for the interface between a policy server and network nodes. In this language, a policy rule can be composed using predefined primitive building blocks and control structures.

Introduction to this research theme: Policy-based Networking

Kanada, Y., 2nd International Working Conference on Active Networks (IWAN 2000), Lecture Notes in Computer Science, No. 1942, pp. 195-210, Springer, October 2000.

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[ Paper PDF file ] [ OHP PDF file ]

Abstract: Policy-based networks can be customized by users by injecting programs called policies into the network nodes. So if general-purpose functions can be specified in a policy-based network, the network can be regarded as an active network in the wider sense. In a policy-based network, two or more policies must often cooperate to provide a high-level function or policy. To support such building-block policies, two architectures for modeling a set of policies have been developed: pipe-connection architecture and label-connection architecture. It is shown that rule-based building blocks are better for policy-based network control and that the label-connection architecture is currently better. However, the pipe-connection architecture is better in regards to parallelism, which is very important in network environments.

Introduction to this research theme: Policy-based Networking

Kanada, Y., IEICE SIG on Information Network, Technical Reports, 100-378, IN 2000-102, pp. 47-54, October 2000.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ]

Abstract: In a policy-based network, two or more policies must often cooperate to provide a high-level function or policy. To support such building-block policies, two architectures for modeling a set of policies have been developed: pipe-connection architecture and label-connection architecture. It is shown that rule-based building blocks are better for policy-based network control and that the label-connection architecture is currently better. However, the pipe-connection architecture is better in regards to parallelism, which is very important in network environments.

Introduction to this research theme: Policy-based Networking

Kanada, Y., Workshop on Policies for Distributed Systems and Networks (Policy 2001), Lecture Notes in Computer Science, No. 1995, Springer, pp. 171-184, January 2001.

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[ Paper PDF file ] [ OHP PDF file ]

Abstract: To control complicated and decomposable networking functions, such as Diffserv, two or more policies must cooperate. Combining two or more mutually dependent policies for a specific purpose is called policy combination. Methods of passing information between combined policies can be classified into real tags and virtual tags, or labels and attributes. Policy combinations can be classified into concatenation, parallel application, selection, and repetition. Explicitly specifying policy combinations makes policy systems semantically clearer and better suited to general use, extends the range of functionality, and improves the possibility of optimization. If policy combinations can be specified in a policy system, two types of policy organizations can be distinguished: homogeneous and heterogeneous. Heterogeneous organization is more service-oriented and seems to meet service-management requirements, but homogeneous organization is more device-oriented and may provide better performance.

Introduction to this research theme: Policy-based Networking

Kanada, Y., 7th IFIP/IEEE International Symposium on Integrated Network Management (IM 2001), pp. 545-560, May 2001.

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[ Paper PDF file ] [ OHP PDF file ]
[ IEEExplore Paper page ]

Abstract: Because higher- and lower-level policies do not necessarily correspond one to one, a higher-level network policy may have to be translated into two or more lower-level policies, and two or more cooperating higher-level policies may have to be translated into one lower-level policy. The former transformation is called a policy division, and the latter transformation is called a policy fusion. These transformations can be performed mechanically under restricted conditions as described in this paper. However, in general, they are very complicated and the restrictions cannot be eliminated completely mainly because of existence of multiple packet classifiers in a set of policies. Thus, this paper concludes that they should not be introduced if it is possible. The policy division and fusion can be avoided in certain cases, but they will not probably be able to be avoided in general. If so, the problem should be solved or relaxed by removing harmful classifiers by introducing virtual flow labels and by further studies. In addition, we may have to find a better method to control network devices than policies in the current sense.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and O'Keefe, B. J., Asia-Pacific Network Operations and Management Symposium 2001 (APNOMS 2001), September 2001, (poster paper, presentation cancelled)

[ 日本語のページ ]
[ Paper PDF file ] [ Unpublished paper PDF file ]

Abstract: Policies sometimes have to be combined and applied in cooperation to represent such programmable and customizable network functions as Diffserv. In the OpenView PolicyXpert and JP1/PolicyXpert policy servers, three types of policies and three types of virtual flow labels, to connect the policy rules, are defined for Diffserv. The combination of these policies allows the representation of complex Diffserv policies and the separation of service and subscriber policies. Diffserv policies and virtual flow labels make this possible. However, the careful design of Diffserv policies has enabled simple Diffserv policies to be represented in a simple form.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and O'Keefe, B. J., SIG Information Networks & SIG Network Systems, Institute of Electronics, Information and Communication Engineers (IEICE), March 2002.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]

Abstract: In policy-based networking, policies sometimes have to be combined and applied in cooperation to represent such programmable and customizable network functions as Diffserv. For a policy server called PolicyXpert, we have designed and implemented three types of policies and three types of virtual flow labels (VFLs) to connect the policy rules. The policy combination enables the representation of complex Diffserv policies. Policy combination also allows sub-classing of DSCP-based service classes, and the separation of service and subscriber policies. The careful design of Diffserv policies has enabled simple Diffserv policies to be represented in a simple form.

Introduction to this research theme: Policy-based Networking

Kanada, Y., Information and Communication Engineers (IEICE) Yearly Conference，2002-3.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ] [ OHP PDF file (in Japanese) ]

Abstract: (Not available)

Introduction to this research theme: Policy-based Networking

Kanada, Y., and Yazaki, T., Communications Quality and Reliability 2002 (CQR 2002), pp. 12-16 2002.

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[ Paper PDF file ] [ OHP PDF file ]

Abstract: In policy-based networks, two or more policies often have to cooperate because combined and customized network functions must be controlled using policies. Two types of policy trans-formation, policy fusion and policy division, are sometimes required to implement cooperating policy systems on high-performance hardware routers. Policy fusion transforms two or more policies into one, and policy division transforms a policy into two or more policies. These transformations causes a problem that the original policies must usually be strongly constrained to allow these transformations. This paper shows a method for resolving restrictions on the division of QoS policies by a software-hardware integration, i.e., by implementing virtual flow labels (flow IDs) in hardware and by dividing a policy and deploying the policies onto two filter blocks. We have developed a policy agent (PEP) and a gigabit router integrated by using this method. Both high-performance and flexibility are achieved by this integration.

Introduction to this research theme: Policy-based Networking

Kanada, Y., 3rd International Workshop on Policies for Distributed Systems and Networks (Policy 2002), pp. 236-239, June 2002, http://dx.doi.org/10.1109/policy.2002.1011316
[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]
[ IEEExplore Paper page ]

要約: This paper proposes a method, called the policy-extension-by-policy method, for quickly and dynamically adding policy classes with new functionality to policy servers and agents. In this method, users can add a new policy class to the policy server by using policy-definition (PD) policies, and they can define a method to translate a policy of the new class and to send to network nodes of different vendors through various types of device interfaces, such as CLI, MIBs, PIBs, APIs or hardware tables, by using policy-embedding (PE) policies. A PE policy also enables translating a policy of an existing class and sending the result to a new type of network node. PE policies contain command templates and methods for filling the templates. A program interpreter is embedded in policy agents to make flexible policy-to-configuration translation possible. A prototype system and example policies, i.e., access control, Diffserv, and VPN policies, were developed.

Introduction to this research theme: Policy-based Networking

Kanada, Y. and O'Keefe, B. J., Journal of Network and Systems Management, Vol. 11, No. 3, pp. 253-275, 2003.

[ 日本語のページ ]
[ JNSM Issue Web Page ] [ Paper PDF file (draft) ]

Abstract: We developed two rule-based building-block architectures, i.e., pipe-connection and label-connection architectures, for describing complex and structured policies, especially network QoS policies. The latter is focused on in this study. The relationships or connections between building blocks are specified by the da-taflow and control flow between them. The dataflow is specified by tags, including virtual flow labels (VFLs), which are data attached to "outside packets". The control flow can be classified and specified by four control structures: concatenation, parallel application, selection, and repetition. We have designed fine-grained and coarse-grained building blocks and methods for specifying dataflow and control flow in differentiated services (Diffserv), and implemented the coarse-grained ones in a policy server. Two cases of building-block use are described, and we concluded that there are five advantages of building-block-based policies, i.e., expressibility, uniform semantics, simplicity, flexibility, and management-task-oriented design. We also developed techniques for transforming building-block policies into executable ones, which are called policy division and fusion.

Introduction to this research theme: Policy-based Networking

Kanada, Y., Technical Committee on Internet Architecture (IA), Information and Communication Engineers (IEICE), October 2003.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]

Abstract: As part of research toward establishing voice communication media that shall replace telephone, we developed an architecture and a prototype of a continuously-connected multi-user communication medium called voiscape. A virtual "sound room" that is created by spatial audio technology is used in voiscape. When the user moves within the sound room by using a mouse, the presence information including the position in the room is distributed to other users of the room. If the user becomes closer to or more distant from another user, the communication session begins or ends automatically by using SIP according to predefined policy stored in the terminals. This policy-based session control enables privacy protection and reduction of communication. When a local site requires a session start, the remote site often requires a session start concurrently, so a method of establishing a connection without connecting doubly nor becoming busy was deviced.

Introduction to this research theme: voiscape

Kanada, Y., Technical Committee on Multimedia and Virtual Environment (MVE), Information and Communication Engineers (IEICE), October 2003.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ] [ OHP PDF file (in Japanese) ]

Abstract: The concept of a new communication medium called voiscape is proposed. A virtual "sound room" that is based on the spatial audio technology is shared among the users in voiscape, and a person can move freely in the room, can meet and depart from other people, and can talk with two or more persons by using voiscape. By enabling transmission of presence and peripheral information, voiscape will cover from a telephone-style one-to-one conversation to a variety of communication types that are impossible in conventional media, and will enable sharing the feeling of connection and releaf and sharing tacit knowledge. This paper describes usage scenes and a procedure of voiscape and also describes a PC-based prototype. In this prototype, the user can confirm the situation in front by 3D graphics, and can move around the room by using a mouse.

Introduction to this research theme: voiscape

Kanada, Y., Distributed Processing Systems SIG, Information Processing Society of Japan, March 2004.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ] [ OHP PDF file (in Japanese) ]

Abstract: The author researches toward establishing voice communication media called voiscape which shall replace telephone. A virtual "sound room" that is created by spatial audio technology is used in voiscape. We developed a prototype on PCs, in which 3-D graphic is used for supplementing spatial autio. In this prototype, JMF (Java Media Framework) was used for voice capturing and communication, and Java 3D was used for spatial audio and 3-D graphics. Before the development, the author had believed that the basic functions required for the prototype would be realized by connecting these APIs. However, in fact, they cannot be connected directly, so we used OpenAL through the interface of Java 3D. We also encountered problems of sound quality degradation and delay, but they have been almost solved by refining the program by trial and error.

Introduction to this research theme: voiscape

Kanada, Y., 2nd IASTED International Conference on Communication and Computer Networks (CCN 2004), November 2004.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]

Abstract: A new voice communication medium, which the author calls "voiscape", will probably appear in near future. Voiscape shall have much improved user interface than the conventional voice communication systems, i.e., telephone and conference systems, and be based on the IP-based conferencing and spatial audio technologies. The author has developed a prototype toward voiscape, which has made a step toward solving two problems of the conventional systems i.e., complicated and restricted conference control and lack of crossed-over multi-context support, by introducing two features. The first function is the virtual-location based communication; i.e., the users can talk with other users and move, in a way similar to face-to-face conversation, in a virtual auditory space created by spatial audio technology without explicit session and floor control. The second function is personalized policy-based communication control; i.e., the users can specify communication policies that protects their privacy and reduce required resources. This function is enabled by a distributed policy-arbitration mechanism. Experiments showed that the basic mechanisms and the policy-based control with a simple policy worked well.

Introduction to this research theme: voiscape

Kanada, Y., 15th ACM International Workshop on Network and Operating System Support for Digital Audio and Video (NOSSDAV 2005), pp. 45-50, June 2005, http://dx.doi.org/10.1145/1065983.1065996

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]

Abstract: An improved prototype of the "voiscape" voice communication medium has been developed and subjectively evaluated. Voiscape enables natural and seamless voice communication by using sound to create a virtual "sound room" in which people, who are represented by different sounds, can move freely. It features low-delay motion-tracking spatial audio with simulated early reflections that produce out-of-head sound localization and sound distance expression. It also features virtual-location-based selective communication: a user can walk freely in the sound room using a map- and cursor-key-based user-interface and can select whom to talk to or which sound sources to listen to. A third feature is SIP-presence-event-notification (SIMPLE)-based sound room management: when users move, their locations and directions are distributed using SIP SUBSCRIBE/NOTIFY messages. The combination of these features creates a natural voice-communication space in which two or more parallel conversation contexts can coexist. Limited, subjective testing by around 200 people showed that this medium can be used for cocktail-party-like conversation; i.e., users could distinguish parallel conversations by paying attention to or by moving toward one of them.

Introduction to this research theme: voiscape

Kanada, Y., Technical Committee on Electrical Acoustics (EA), Information and Communication Engineers (IEICE), June 2005.

[ 日本語のページ ]
[ Paper PDF file ] [ OHP PDF file ]

Abstract: We are developing a communication medium called voiscape, which enables taking to people while selecting persons to talk by moving in a virtual "sound room". In the second prototype of voiscape called VPII, the FIR Method is used for low-delay HRTF filtering, the sound room - the range of motion - is identified with the room in acoustical cal-culation, and early reflections by the sound room walls are simulated. The early reflections produce out-of-head sound lo-calization and sound distance expression. We also implemented motion-tracking and interpolation algorithms into the spatialization method. VPII enabled a voice communication environment, in which speaker identification is easy, multiple conversation-contexts can be created in a room, and motions of users and objects in a sound room are natural and causes only small noises.

Introduction to this research theme: voiscape

Kanada, Y., Asia-Pacific Network Operations and Management Symposium 2005 (APNOMS 2005), September 2005.

[ 日本語のページ ]
[ Short paper PDF paper ] [ Poster PDF paper ] [ Unpublished full paper PDF v ]

Abstract: A method for conference-room management for an auditory-virtual-space-based voice-communication medium called voiscape and a voice-communication system prototype called VPII, which used this method, were developed. With this method, conference rooms (called sound rooms) are managed through SIP and SIMPLE (a presence-related event-notification mechanism). A user can not only obtain a room list and enter (select) or exit from a room, but can also create, modify, or delete rooms by SIMPLE messaging. Rooms, users, and objects are managed by their "soft state"; i.e., they are deleted when a time out occurs. Users are informed of room membership, presence of a user, e.g., location and direction in the room, and presence of an object in the room by SIMPLE messaging, i.e., by SUBSCRIBE, NOIFY, and PUBLISH requests. To reduce the messaging overhead, the partial notification mechanism of SIMPLE is used in VPII.

Introduction to this research theme: voiscape

Kanada, Y., 13th ACM International Conference on Multimedia, pp. 794-795, November 2005, http://dx.doi.org/10.1145/1101149.1101319

[ 日本語のページ ]
[ Paper PDF file ] [ Poster PDF File ]

Abstract: We are developing a new voice communication medium called voiscape. Voiscape enables natural and seamless bi-directional voice communication by using sound to create a virtual sound room. In a sound room, people can feel others' direction and dis-tance expressed by spatial sounds with reverberations, and they can move freely by using a map of the room. Voiscape enables multi-voice-conversations. In a virtual market place that will be realized by voiscape, people can not only buy goods or information but also enjoy talking with merchants and people there. In this demo, a vois-cape prototype called VPII is used for realizing such an environ-ment. Unfortunately, because prerecorded voices are used in this demo, the participants cannot talk with merchants. However, the participants can talk each other with small end-to-end latency (less than 200 ms) and will feel the atmosphere of the virtual market place. Prerecorded people and merchants talk each other in English, Japanese and Chinese in parallel and with crossovers, and partici-pants can virtually walk among them and can selectively listen one voice or hear multiple voices at once.

Introduction to this research theme: voiscape

Kanada, Y., IEICE Technical Committee on Communication Quality (CQ), Technical Reports, July 2007.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ]

Abstract: A method for scalable QoS guarantee, in which QoS requirements are signaled by using a protocol similar to RSVP or NSLP and are aggregated in backbones, has been developed and prototyped. The requirements are propagated to the policy server by using policy-based routing and a policy outsourcing protocol. The policy server estimates the amount of traffic and controls the bandwidth sharing among the queues (WFQs) of the backbone routers. The effect of core traffic control has been evaluated by using an L3-switch GS4000 and bursty traffic generated by the MMPP model. The results showed that, if there are many conversational video and streaming traffics, the QoS requirements of both types of traffic can be satisfied by relatively increasing the weight of the former than that of the latter in some cases.

Introduction to this research theme: Policy-based Networking

Kanada, Y., Technical Committee on Electrical Acoustics (EA), Information and Communication Engineers (IEICE), EA2007-42, August 2007.

[ 日本語のページ ]
[ Paper PDF file (updated after the SIG) (in Japanese) ]
[ Paper PDF file (draft) (in Japanese) ]

Abstract: Voiscape is a communication medium by which people can talk each other while moving within virtual sound space freely. By using a prototype of voiscape called VPIIQ (Voiscape Prototype II Q), the effect of difference of QoS caused by network policies was evaluated subjectively. The result showed unexpectedly that the percentage of correct answers was higher in the case in which QoS is lower in the localization test. In the sound localization tests, the percentage of correct answers was higher when subjects performed operations to move or to turn than not to do so. However, in the speaker recognition tests, opposite results were observed.

Introduction to this research theme: voiscape

Kanada, Y., IEICE Communication Society Convention, 2007.

[ 日本語のページ ]
[ Paper PDF file (in Japanese) ]

Currently no abstract is available.

Introduction to this research theme: Policy-based Networking

Kanada, Y., not yet published (April 2008).

[ 日本語のページ ]
[ 論文 PDF ファイル ]

Abstract: Real-time and multimedia applications require an end-to-end QoS guarantee, and various types of applications require various QoS conditions. A DiffServ network should guarantee different QoS conditions for different types of communications. In this paper, the effect of traffic control in a DiffServ core network is experimentally evaluated using bursty traffic generated by an MMPP (Markov-Modulated Poisson Process) model. The situation to be simulated is that there are hundreds of conversational video streams that are delay-sensitive and hundreds of streaming videos that are loss-sensitive. If there are bandwidth-sharing queues such as those follow WFQ (Weighted Fair Queuing) in the core no-des and the two types of video traffic are assigned to two of the queues, the requirements of both types of traffic can be satisfied in a better way (a more efficient way) by assigning a larger weight to the queue for the conversational video. In our experiment, the optimum ratio of the weights was ap-proximately 1.3 when the traffic rates were the same. The optimum weight shares depend on the nature of the traffic, especially the burstiness.

Kanada, Y., The International Conference on Information Networking 2008 (ICOIN 2008), I-1, January 2008, http://dx.doi.org/10.1109/icoin.2008.4472753
[ 日本語のページ ]
[ Paper PDF file ]
[ IEEExplore Paper page ]

Abstract: Real-time and multimedia applications require an end-to-end QoS guarantee, and various types of applications require various QoS conditions. A DiffServ network should guarantee different QoS conditions for different types of communications. In this paper, the effect of traffic control in a DiffServ core network is experimentally evaluated using bursty traffic generated by an MMPP (Markov-Modulated Poisson Process) model. The situation to be simulated is that there are hundreds of conversational video streams that are delay-sensitive and hundreds of streaming videos that are loss-sensitive. If there are bandwidth-sharing queues such as those follow WFQ (Weighted Fair Queuing) in the core no-des and the two types of video traffic are assigned to two of the queues, the requirements of both types of traffic can be satisfied in a better way (a more efficient way) by assigning a larger weight to the queue for the conversational video. In our experiment, the optimum ratio of the weights was ap-proximately 1.3 when the traffic rates were the same. The optimum weight shares depend on the nature of the traffic, especially the burstiness.

Introduction to this research theme: Policy-based Networking

Kanada, Y., IEICE Technical Committee on Network Systems (NS), 2009-4-16.

[ 日本語のページ ]
[ Paper PDF file ]

Abstract: A method of admission control based on both resource requests by applications and traffic measurement results per DiffServ class using NetFlow was developed. Several experiments using a newly-developed policy-server prototype using this method and simulated voice traffic showed that bandwidth usage can be improved and call blocking ratio was decreased with low measurement load by using this method. Interesting but possibly harmful dynamics were observed by simulations using simulated traffic that follows an on/off model; i.e., this admission control method may cause oscillation or long-term development that lasts for 100 to 150 minutes, and it may also cause bandwidth overshooting. The range of parameters, with which such phenomena can be properly suppressed and the admission control correctly works, was experimentally obtained.

Introduction to this research theme: Policy-based Networking

Kanada, Y., 5th Advanced International Conference on Telecommunications (AICT 2009), May 2009, http://dx.doi.org/10.1109/aict.2009.16 [The presentation was canceled because of the new type of influenza.]

[ 日本語のページ ]
[ Paper PDF file ]
[ IEEExplore Paper page ]

Abstract: A method of admission control based on both resource requests by applications and class-based traffic mea-surement results was developed. In this method, a wide range of admission-control policy can be realized by adjusting three parameters, , , and . A policy-server prototype using this method and simulated voice traffic was used in traffic measurements. The measurements results show that the proposed method improves bandwidth usage and decreases call-blocking ratio while incurring low measurement load. Interesting but possibly harmful dynamics (i.e., system behavior) were observed by the simulations using traffic generated by an on/off model. That is, this admission-control method may cause oscillation or long-term evolution that lasts for 100 to 150 minutes, and it may also cause bandwidth “overshooting”. The range of parameters with which such effects can be properly suppressed and the admission control correctly works was experimentally obtained.

Introduction to this research theme: Policy-based Networking

Kanada, Y., IEICE Technical Committee on Information Networks (IN), 2009-5-21.

[ 日本語のページ ]
[ Paper PDF file (C) IEICE ]

Abstract: A mechanism for users to input a request on quality of experience (QoE) and for the network to satisfy the request. A QoE request is mapped to QoS, and it is satisfied by using admission control and network node configurations. By using a soft-state protocol for the request, service initiation, extension, and termination are handled in a unified method. Part of this mechanism has been built into a prototype, and tested using a network node with so-called hierarchical shaper and using video streaming, the mechanism has been confirmed to work in a designed way.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and Nakao, A., IEICE Technical Committee on Information Networks (IN), 2010-9-2.

[ 日本語のページ ]
[ Paper PDF file (C) IEICE (in Japanese) ]
[ Slides PDF file (in Japanese) ]

Abstract: In the National Institute of Information and Communications Technology (NICT), 10-Gbps-class virtualization nodes (VNodes) that enables implementing non-IP protocols with any frame format are developed using network-virtualization technology. We have developed an experimental non-IP protocol called IPEC (IP Ether Chimera) on a virtual network us-ing the VNodes. In IPEC, the nodes learn addresses that can be hierarchical such as IP addresses using an algorithm that extends Ethernet switch learning algorithm. IPEC has the following features. First, IPEC realizes a simple single-layer non-IP protocol that has features of both Ethernet and IP. Second, because a group is the unit of learning in IPEC, it is more scalable than Ethernet, and mobile groups can be more efficiently learned. Third, this forwarding algorithm can be used in networks with loops and it can forward packets during failure using an alternative route. Group IDs can be used as locators, so IPEC can be regarded to realize an architecture that extends ID/Locator separation architecture. We implemented IPEC on VNodes, and confirmed that it enabled group learning and group mobility by experiments.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and Nakao, A., IEICE Technical Committee on Internet Architecture (IA), 2010-12-17.

[ 日本語のページ ]
[ Paper PDF file (C) IEICE (in Japanese) ]
[ Slides PDF file (in Japanese) ]

Abstract: The virtualization-node project at the National Institute of Information and Communications Technology (NICT) is developing 10-Gbps-class virtualization nodes (VNodes) that enables implementing non-IP protocols with any frame format using network-virtualization technology. In this project, because the VNodes have been introduced into the R & D test-bed network called JGN2plus, an important challenge is to improve usability for developers (JGN2plus users). There-fore, we developed and tested a non-IP protocol called IPEC (IP-Ether-Chimera) on the experimental network using the VNodes, described the procedure and experiments, and extracted the problems and knowhow concerning usability. A problem to solve is to develop methods for avoiding careless mistakes by developers, and an obtained knowledge is that a combination of a small-scale experiment using connected several Linux PCs and a scaled-up experiment on wide-area network reduced the complexity of the development. This experiment did not need wide bandwidth, but this method will enable scaling up the experiment utilizing 10-Gbps bandwidth relatively easier.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and Tarui, T., 10th International Conference on Networks (ICN 2011), 2011-1-24.

[ 日本語のページ ]
[ Paper PDF file (C) IARIA ]
[ ThinkMind Paper page ]
[ Slides PDF file ]

Abstract: Two network-virtualization architectures, namely, network segmentation and network paging, were investigated. They are analogical to two memory-virtualization architectures: segmentation and paging. Network paging, which is relatively new and is based on a type of network-address translation (NAT), is focused on. This architecture requires smaller packet size and has several more advantages over the conventional architecture (i.e., network segmentation). Intranet- and extranet- type communication methods based on this architecture are described. An address translators is placed at each edge router in the WAN and used to evaluate client-server communication under wide-area virtual-machine (VM) live migration as a case of extranet-type communication.

Introduction to this research theme: Policy-based Networking

Kanada, Y., and Tarui, T., 25th International Conference on Information Networking (ICOIN 2011), January 2011, http://dx.doi.org/10.1109/icoin.2011.5723191
[ 日本語のページ ]
[ Paper PDF file ]
[ IEEExplore Paper page ]

Abstract: In cloud-computing environments, migration of virtual machines (VMs) between data centers can solve many problems such as load balancing and power saving. One of the difficulties in wide-area migration, however, is the “address-warping” problem, in which the address of the VM warps from the source server to the destination server. This confuses or complicates the status of the WAN, and the LANs connected to the WAN. We propose two solutions to this problem. One is to switch an address-translation rule, and the other is to switch multiple virtual networks. The former is analogous to paging in memory virtualization, and the latter is analogous to segmentation. The “network-paging” based method is described and our evaluation results are shown. It took less than 100 ms in average to switch from the source to the destination server using this method.

Introduction to this research theme: Policy-based Networking

Kanada, Y., Tarui, T., and Shiraishi, K., IFIP/IEEE International Symposium on
Integrated Network Management (IM 2013), 2013-5.
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides ]

Abstract: A method for federating multiple network-virtualization platforms by creating and managing slices (virtual networks) is proposed. A cross-domain slice can be created, deleted, or modified by sending a slice specification to the domain controller (network manager) of one domain. The specification is then propagated to other domains. Two chal­lenges were addressed while this method was developed. The first challenge is to enable federation among multiple domains that do not support federation functions by only adding a few components without modification of the existing network-virtualization-platform architecture. A domain-dependent specification of a slice, containing a pseudo virtual node that encloses a part of the slice specification in the other domains, is used, and this part is handled by a proxy node that represents another domain and a control component that implements a federation API to create a cross-domain slice. The second challenge is to enable manageable non-IP (arbitrary-format) data communication on a cross-domain slice. For an inter-domain communication, underlay VLAN parameters including MAC addresses are negotiated in advance and data packets on a slice are tunneled between gateways in these domains. The proposed federation method was implemented on two network-virtualization platforms, federation between two homogeneous domains was successfully demonstrated, federation perfor­mance was measured, and several issues on functional restrictions and implementation difficulty were found.

Introduction to this research theme: Network virtualization

Kanada, Y., IEICE 7th Network Virtualization SIG, July 2013.
[ 日本語ページ ]
[ Paper PDF file ]
[ Slides ]

Abstract: Network processors are used for high-performance programmable networks. However, programs for net- work processors are limited in portability and number of developers, so the development cost is high. To solve this problem, open, high-level, and portable programming language called “CSP” and a development environment called “+Net” have been developed. In this environment, high throughput can be obtained without programmers’ signifi- cant awareness of SRAM/DRAM distinction. A prototype using Cavium Octeon, a network processor, has been de- veloped, and it performs 7.5 Gbps or more in simple programs in an evaluation using part of the network virtualization platform.

Introduction to this research theme: Network virtualization

Kanada, Y., and Tarui, T., Network Virtualization Symposium 2013, September 2013.
[ 日本語のページ ]
[ Poster PDF file ]

Summary: VNode enabled mutually independent evolution of programmers and redirectors. In this presentation, a method for evolving VNodes and developing new species of virtual links by using both control and data plug-ins and a publicly available testbed is proposed.

Introduction to this research theme: Network virtualization

Kanada, Y., 2013 Workshop on
Software Defined Networks for Future Networks and Services (SDN4FNS 2013), November 2013, http://dx.doi.org/10.1109/sdn4fns.2013.6702531
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides ]

Abstract: Virtualization nodes, i.e., physical nodes with network virtualization functions, contain computational and networking components. Virtualization nodes called “VNodes” enabled mutually independent evolution of computational component called programmer and networking component called redirector. However, no methodology for this evolution has been available. Accordingly, a method for evolving programmer and redirector and developing new types of virtualized networking and/or computational functions in two steps is proposed. The first step is to develop a new function without updating the original VNode, which continues services to existing slices, using a proposed plug-in architecture. This architecture defines predefined interfaces called open VNode plug-in interfaces (OVPIs), which connect a data and a control plug-ins to a VNode. The second step is to merge the completed plug-ins into the original programmer or redirector. A prototype implementation of the above plug-in architecture was developed, tested, and evaluated. The prototype extends the redirector by adding new types of virtual links and new types of network accommodation. Estimated throughputs of a VLAN-based network accommodation and a VLAN-based virtual link using network processors are close to a wire rate of 10 Gbps.

Introduction to this research theme: Network virtualization

Kanada, Y., 1st IEEE/IFIP International Workshop on SDN Management and Orchestration (SDNMO 2014), May 2014, http://dx.doi.org/10.1109/noms.2014.6838417
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides ]

Abstract – Network virtualization introduces two concepts: slice (i.e., virtual network), which consists of virtual nodes and links, and slice developer, which is the third role in networks. Slice developers can introduce new network services by using slices. A method for introducing new types of virtual nodes and links for new services into the slicedefinition language and the virtualization infrastructure by evolving physical nodes (i.e., “virtualization nodes” or VNodes) is proposed. This evolution consists of two stages: the experimental stage and the operational stage. In the experimental stage, data and control plug-ins are developed and tested by the operator or vendor by using experimental sliver definitions. In the operational stage, which is focused on in this study, the plug-ins are integrated into original components in the infrastructure and are available for slice development by using normal sliver definitions. By mapping type names to plug-in identifiers and parameters, the proposed method enables abstract and simple definitions of slices by slice developers and authorization of plug-ins by the operator, but it remains the loose integration of the new function, i.e., the plug-in architecture used in the experimental stage. Prototyping and evaluation demonstrates that this method greatly simplifies both slice developers’ tasks and operators’ tasks.

Introduction to this research theme: Network virtualization

Kanada, Y., 2nd International Workshop on Network Management and Monitoring (NetMM 2014), May 2014, http://dx.doi.org/10.1109/waina.2014.112
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides PDF file ]

Abstract – A network processor (NP) usually contains multiple packet processing cores (PPCs) and a control processing core (CPC), and the synchronization and communication between CPC and PPCs, which is required for controlling an NP, is very complex. To reduce the complexity, a method for controlling packet processing in NPs by using PPCs is proposed. By means of this method, complex control messages are partially processed and divided into simplified control packets by a CPU outside the NP chip, and these packets are sent to a control-processing PPC. The control-processing PPC controls data-processing PPCs by using data-exchange mechanisms, such as a shared memory or an on-chip network, which are more uniform and simpler than those between a CPC and PPCs. This control method is applied to a virtual-link controlprocessing task and packet-processing tasks in a network node with a virtualization function. Both tasks are described by a hardware-independent high-level language called “Phonpl,” and communication between the PPCs is programmed following normal and uniform shared-memory semantics. As a result, programming the control-processing task and porting the program become much easier.

Introduction to this research theme: Network virtualization

Yasusi Kanada, ACM SIGPLAN Workshop on Memory Systems Performance and Correctness (MSPC 2014), poster, June 2014.
[ 日本語のページ ]
[ Poster photo ]
[ Draft poster ]

Introduction to this research theme: Network virtualization

Kanada, Y., 29th edition of the International Conference on Information Networking (ICOIN 2015), January 2015, http://dx.doi.org/10.1109/ICOIN.2015.7057953.
[ 日本語のページ ]
[ Paper PDF file ]
[ Poster PDF file ]
[ Simulator program ]

Abstract – Many commercial and open-source network simulators are available; however, most of them are not suited for novices in college and school education or learning. Moreover, although Ethernet has recently become much more important, simulators that can be used for this purpose is rare because most simulators suited for education and learning are designed for IP communication. The author developed a simple CLI-based Ethernet simulator that can display contents of Ethernet packets to send or to receive in terminals and contents of MAC address tables in switches in “real time”, and used the simulator in a university class for learning computer networks. The simulator, which is in public domain, is written in Python and, thus, runs on Windows, Macintosh, Linux, and other operating systems. The use of this simulator was evaluated based on a report assignment. The evaluation result shows that the average score of the reports written by using the simulator was much better, although it is not statistically significant because the number of students is small. The simulator seems to be effective to learn behaviors of Ethernet-based networks.

Poster display photo

Kanada, Y., Communications and Network, Vol. 7, pp. 55-69, http://dx.doi.org/10.4236/cn.2015.71006
[ Japanese page ]
[ paper PDF file ]

Abstract – Network processors (NPs) are widely used for programmable and high-performance networks; however, the programs for NPs are less portable, the number of NP program developers is small, and the development cost is high. To solve these problems, this paper proposes an open, high-level, and portable programming language called “Phonepl”, which is independent from vendor-specific proprietary hardware and software but can be translated into an NP program with high perfor- mance especially in the memory use. A common NP hardware feature is that a whole packet is stored in DRAM, but the header is cached in SRAM. Phonepl has a hardware-independent abstrac- tion of this feature so that it allows programmers mostly unconscious of this hardware feature. To implement the abstraction, four representations of packet data type that cover all the packet op- erations (including substring, concatenation, input, and output) are introduced. Phonepl have been implemented on Octeon NPs used in plug-ins for a network-virtualization environment called the VNode Infrastructure, and several packet-handling programs were evaluated. As for the eval- uation result, the conversion throughput is close to the wire rate, i.e., 10 Gbps, and no packet loss (by cache miss) occurs when the packet size is 256 bytes or larger.

Kanada, Y., 13th SIG Meeting on Network Virtualization, March 2015.
[ 日本語ページ ]
[ Poster photo ]

Summary: In IP/Ethernet-based networks, redundant addresses, both IP and MAC addresses, are used. Problems caused by this redundancy can be solved by replacing IP/Ethernet by IP/null (IPON) protocol. It was implemented using VNodes.

Introduction to this research theme: Network virtualization

Kanada, Y., Journal of Information Processing, Vol. 24, No. 6, pp. 908–916, November 2016.

[ 日本語のページ ]
[ Paper PDF file ]
[ Paper PDF file (Japanese version (refereed) -- not published) ]

Abstract: When manufacturing or 3D-printing a product using a computer, a program that procedurally controls manufacturing machines or 3D printers is required. G-code is widely used for this purpose. G-code was developed for controlling subtractive manufacturing (cutting work), and designers have historically written programs in G-code, but, in recently developed environments, the designer describes a declarative model by using computer-aided design (CAD), and the computer converts it to a G-code program. However, because the process of additive manufacturing, of which FDM-type 3D-printing is a prominent example, is more intuitive than subtractive manufacturing, it is some- times advantageous for the designer to describe an abstract procedural program for this purpose. This paper therefore proposes a method for generating G-code by describing a Python program using a library for procedural 3D design and for printing by a 3D printer, and it presents use cases. Although shapes printable by the method are restricted, this method can eliminate layers and layer seams as well as support, which is necessary for conventional methods when an overhang exists, and it enables seamless and aesthetic printing.

Introduction to this research theme: 3D shape formation technologies