온톨로지 매핑 정보를 이용한 웹 서비스 자동발견

송재경,김도현,변영철,이상준 제주대학교 공과대학 첨단기술연구소 2004 尖端技術硏究所論文集 Vol.15 No.2

Web Service is a new model based on web to offer dynamic information for a user's request. Currently, the web service discovery mechanism is not efficient because it does not support automatic discovery based on the semantics or capabilities of a web service. The language for semantic web service, such as OWL-S, is being developed to express the capability of a web service semantically. Such semantics can support the more flexible discovery of web services. Web service discovery occurs when the provider's description matches to that of requester. But the matching can fail when the ontologies of service description differ from that of the requester although the requester wants that Web Service. In distributed environment service providers develope their semantic web services independently and tend to use their ontologies to describe web services. So a new approach must be required to avoid service discovery failure. In this paper, a method of annotating the query of requester and discovering semantic web services without service discovery failure is proposed.

CLAM 에이전트 기반 Directory Facilitator를 위한 효율적인 서비스 디스커버리 프로토콜 구현

이승현,신동렬,장경수,Lee, Seung-Hyun,Shin, Dong-Ryeol,Jang, Kyung-Soo 한국인터넷방송통신학회 2011 한국인터넷방송통신학회 논문지 Vol.11 No.6

현재, UPnP, Jini, SLP와 같은 서비스 디스커버리 프로토콜은 서비스의 표현과 기술, 그리고 메시지 교환 패턴과 같은 기본적인 서비스 디스커버리 기능만 제공한다. 이것은 서비스 디스커버리 프로토콜 사이에 서비스의 상호운영성을 저해하는 요소로 작용한다. 따라서, 본 논문에서는 이기종 서비스간의 상호운영성을 높일 수 있도록 CLAM (Component-based Autonomic Layered Middleware) 에이전트 플랫폼을 구성하고, 플랫폼 내의 DF (Directory Facilitator)의 기능을 확장하여 효율적인 서비스가 가능하도록 DF 에이전트를 설계하고 구현한다. 또한 DF 에이전트에서 확장성과 상호운영성을 보장하기 위해 DHT-Chord 알고리즘을 이용한 효율적인 서비스 디스커버리 메커니즘을 제안한다. Current service discovery protocols such as UPnP, Jini, SLP provide the basic function which is message exchange pattern, service representation and description, in service discovery. They does not guarantee service interoperability among service discovery. Therefore, in this paper, we design and implement CLAM (Component-based Autonomic Layered Middleware) agent platform to enable an efficient service discovery through extension of DF agent function in FIPA-compliant specification. Also, we propose an efficient service discovery mechanism using DHT-Chord algorithm to guarantee scalability and interoperability in DF agent.

IoT에서 효율적인 서비스 제공을 위한 이름 기반 서비스 탐색 메커니즘

조국현(Kuk-Hyun Cho),김정재(Jung-Jae Kim),류민우(Minwoo Ryu),차시호(Si-Ho Cha) 한국산학기술학회 2018 한국산학기술학회논문지 Vol.19 No.6

IoT는 다양한 디바이스들이 통신을 통해 사용자에게 서비스를 제공하는 환경이다. IoT의 특성으로 인해 데이터들은 이종간의 정보시스템에 분산되어 저장된다. 이러한 상황에서 IoT 엔드 애플리케이션은 데이터가 어디에 있는지 또는 스토리지의 형태가 어떠한지 알 수 없어도 데이터를 액세스할 수 있어야 한다. 이러한 메커니즘을 SD(Service Discovery)라고 한다. 그러나 현재까지의 SD 구조는 물리적 디바이스를 중심으로 탐색하기 때문에 몇 가지 문제점이 발생한다. 첫째, 물리적 위치에 따른 서비스 탐색으로 인해 반환시간이 증대된다. 둘째, 디바이스와 서비스를 따로 관리하는 데이터 구조가 요구된다. 이는 관리자의 서비스 구성복잡도를 증가시킨다. 이로 인해 디바이스 중심의 SD 구조는 실제 IoT에 적용하기에는 적합하지 않은 구조로 되어 있다. 이러한 문제점을 해결하기 위하여 본 논문에서는 NSSD(Name-based Service Centric Service Discovery)라는 SD 구조를 제안한다. NSSD는 이름 기반의 중앙집중형 SD를 제공하며 IoT 에지 게이트웨이를 캐싱 서버로 사용해 서비스 탐색속도를 향상시킨다. 기존의 DNS와 DHT 기반 DS 구조와의 시뮬레이션을 통해 NSSD가 평균 반환시간에 있어 약 2배 정도 향상된 성능을 제공함을 입증하였다. The Internet of Things (IoT) is an environment in which various devices provide services to users through communications. Because of the nature of the IoT, data are stored and distributed in heterogeneous information systems. In this situation, IoT end applications should be able to access data without having information on where the data are or what the type of storage is. This mechanism is called Service Discovery (SD). However, some problems arise, since the current SD architectures search for data in physical devices. First, turnaround time increases from searching for services based on physical location. Second, there is a need for a data structure to manage devices and services separately. These increase the administrator"s service configuration complexity. As a result, the device-oriented SD structure is not suitable to the IoT. Therefore, we propose an SD structure called Name-based Service-centric Service Discovery (NSSD). NSSD provides name-based centralized SD and uses the IoT edge gateway as a cache server to speed up service discovery. Simulation results show that NSSD provides about twice the improvement in average turnaround time, compared to existing domain name system and distributed hash table SD architectures.

A Platform of Service Registry to Discover Service Resources in Ubiquitous Network

BenYan,Hua-Ping Yao,Masahide Nakamura,Shinsuke Matsumoto,Hideharu Seto 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.9

In a ubiquitous network, a variety of things such as environmental sensor, home appliance and mobile phone are connected to an information network, which can be regarded as a service resource. Combined via network, these service resources can provide value-added ubiquitous services anywhere at anytime. In a future ubiquitous network, it is expected to achieve an adaptive service platform, which can dynamically integrate various service resources to provide adaptive and context-aware services. This paper presents a new service registry platform named UBI-REGI, which is used to support efficient and dynamic discovery of service resources in a ubiquitous network. To define the scope of operation within the real world and IT world, UBI-REGI divides every service operation into three categories: source service, transformation service and sink service. Furthermore, UBI-REGI specifies meta-data like physical location or device owner to manage physical devices, in addition to the conventional meta-data like service name, purpose and description. In order to enable UBI-REGI to be easily used by external program, this paper designs and implements UBI-REGI API by using Web service technologies. With this API, external applications can find service resources by queries of service category, location, purpose keywords, and so on. As a case study, this paper demonstrates an environment continue service in a home network system to prove the feasibility of this proposal.

ASESDP : An Efficient Service Discovery Protocol in Pervasive Computing Environments

Ma, Qianli,Liao, Minghong,Jiang, Shouxu,Hong, Wan-Pyo,Gao, Zhenguo The Korea Institute of Information and Commucation 2008 Journal of information and communication convergen Vol.6 No.4

Service discovery is the technology of finding needed services in networks, and a key point in pervasive computing environments. This paper presents a novel service discovery protocol: ASESDP(AIP and SRR Enhanced Service Discovery Protocol). In ASESDP, tow schemes are proposed to enhance its performance: AIP(Advertisement Information Piggybacked) and SRR(Shortest Reply Route). In AIP, parts of advertisement information are piggybacked in the service reply packet, which makes the advertisement information propagating along the reply path, and spreads its transmission area. In SRR, in order to reduce the service response time, the shortest reply route is chosen to forward the service reply packet to the source node sending the service request. With the theoretical analysis and Glomosim simulation results, it is verified that ASESDP can reduce the number of service request packets, save the response time, and improve the efficiency of service discovery.

모바일 애드 혹 네트워크에서 분산 해쉬 테이블 기반의 서비스 탐색 기법

정재훈(Jaehoon Jung),이승학(Seunghak Lee),김남기(Namgi Kim),윤현수(Hynsoo Yoon) 한국정보과학회 2008 정보과학회논문지 : 정보통신 Vol.35 No.1

Ad hoc 네트워크에서 필요한 서비스를 사용하려면 먼저 원하는 서비스를 어떤 노드가 제공하는지, 또한 이런 서비스를 호출하려면 어떠한 방법을 사용해야 하는지 등의 정보를 알아내야 한다. 본 논문에서는 이러한 문제점들을 해결할 수 있는 DHT(Distributed Hash Table) 기반의 서비스 발견 프로토콜을 제안한다. 제안하는 프로토콜은 중앙 룩업 서버를 요구하지 않고 멀티캐스트나 플러딩을 사용하지 않기 때문에 확장성을 지닌다. 성능평가 결과, 제안하는 프로토콜은 확장성이 있고 기존의 서비스 탐색 프로토콜에 비해 나은 성능을 가짐을 알 수 있었다. In order to get a desired service in such environments, we need a service discovery method for discovering a device providing that service. In this paper, we propose a service discovery protocol which is based on DHTs (Distributed Hash Tables) to solve these problems. Our protocol is scalable since it does not require a central lookup server and does not rely on multicast or flooding. Simulation results show that our protocol is scalable and outperforms existing service discovery protocols.

A Semantic Web Service Discovery System Based on UDDI and OWL-S

Li Peng 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.9

As a popular registry for Web services, UDDI provides a mature mechanism for service registration and search, but it does not support semantic operations on Web services, so its service discovery capability is not satisfactory. OWL-S overcomes UDDI’s shortcomings. Using OWL-S, service advertisements and requests based on capability description could be built in a uniform way, and the semantic matching between them could also be achieved. By means of these two technologies, a system was developed which is compatible with UDDI and supports the publication and discovery of semantic Web services. The matching performed by the system is divided into two parts: pre-matching and post-matching. The pre-matching is generally performed only in the course of service publication, so the time for service discovery is reduced. Experimental results show that the performance of the system is reliable. Furthermore, the system can produce query results ordered by priority according to the requester’s expectations.

분산되어 있는 OSGi 프레임워크에서 효과적인 서비스 공유 방안

윤기현,김은회,최재영 한국정보처리학회 2009 정보처리학회논문지. 컴퓨터 및 통신시스템 Vol.16 No.4

OSGi technology has applied to Home Network, but now it is loaded into even heterogeneous devices in various domains. Therefore, it is necessary to cooperate with each other framework for offering effective services in distributed OSGi frameworks. However until now, OSGi specification doesn’t provide any methodthat can share the services registered on remote OSGi frameworks. In order to solve this problem, there have been several researches that used existing distributed middleware technologies such as JXTA and Web Services. However these technologies have some weakness, that is, they consume lots of computing resources and need additional process to transform the services. A middleware called R-OSGi uses only OSGi technology for sharing remote OSGi services, but R-OSGi may have a communication bottleneck and SPOF (Single Point of Failure) problem, because it has a central service registry. In this paper we present RSP (Remote Service Provider), which is a P2P-based effective service sharing scheme on distributed OSGi framework. RSP doesn’t need to install additional software nor have the additional transformation process of the service representation, because it uses only OSGi technology. In addition it doesn’t have any bottleneck problem and improves scalability by providing the service discovery mechanism using P2P. RSP can also access remote services transparently and it can guarantee reliability by sending an immediate notice about changes of the remote services. 홈 네트워크 분야에서 주로 적용되었던 OSGi 기술은 현재 다양한 도메인의 이질적인 장치에 탑재되고 있다. 분산되어 있는 OSGi 프레임워크 환경에서 효과적인 서비스를 제공하기 위해서는 프레임워크들간의 상호작용이 필수적이다. 하지만 현재까지 공개된 OSGi 스펙에서는 원격 OSGi 프레임워크에 등록된 서비스를 공유할 수 있는 방안을 제공하지 않고 있다. 이와 같은 문제점을 해결하기 위하여 기존의 분산 미들웨어 기술인 JXTA 또는 Web Services를 활용하는 기술들이 연구되었으나, 이러한 기술들은 컴퓨팅 자원을 많이 소모하고 또한 부가적인 서비스 변환과정이 필요하다는 문제점이 있다. R-OSGi는 OSGi 기술만을 사용하여 원격 서비스를 공유할 수 있는 방안을 제공하지만, 중앙집중적인 구조를 가짐으로써 병목현상이나 SPOF (Single Point Of failure)가 발생할 수 있다. 본 논문에서는 P2P 기반의 효과적인 서비스 공유 방안인 RSP (Remote Service Provider)를 제안한다. RSP는 OSGi 자체 기술만을 사용하므로 서비스를 공유하기 위하여 추가적으로 다른 소프트웨어를 설치하거나, 그 소프트웨어를 사용하기 위한 변환과정이 필요 없다. 또한 P2P 방식의 서비스 발견 메커니즘을 사용하여 병목현상을 해결하고 확장성을 높일 수 있다. 그리고 RSP는 원격 서비스에 대한 투명성을 제공하고, 원격 서비스의 상태 변화를 즉각 통보하여 원격 서비스의 신뢰성을 보장하는 특징을 가진다.

Trustworthy Service Discovery for Dynamic Web Service Composition

( Yukyong Kim ),( Jong-seok Choi ),( Yongtae Shin ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.3

As the number of services available on the Web increases, it is vital to be able to identify which services can be trusted. Since there can be an extremely large number of potential services that offer similar functionality, it is challenging to select the right ones. Service requestors have to decide which services closelysatisfy their needs, and theymust worry about the reliability of the service provider. Although an individual service can be trusted, a composed service is not guaranteed to be trustworthy. In this paper, we present a trust model that supports service discovery and composition based on trustworthiness. We define a method to evaluate trust in order to discover trustworthy services. We also provide a method to perform trust estimation for dynamic service composition, and we present results of two experiments. The proposed model allows for service requestors to obtain the most trustworthy services possible. Our mechanism uses direct and indirect user experience to discover the trustworthiness of the services and service providers. Moreover, composing services based on quantitative trust measurements will allow for consumers to acquire a highly reliable service that meet their quality and functional requirements.

An Autonomic <K, D>-Interleaving Registry Overlay Network for Efficient Ubiquities Web Services Discovery Service

Ragab, Khaled Korea Information Processing Society 2008 Journal of information processing systems Vol.4 No.2

The Web Services infrastructure is a distributed computing environment for service-sharing. Mechanisms for Web services Discovery proposed so far have assumed a centralized and peer-to-peer (P2P) registry. A discovery service with centralized architecture, such as UDDI, restricts the scalability of this environment, induces performance bottleneck and may result in single points of failure. A discovery service with P2P architecture enables a scalable and an efficient ubiquities web service discovery service that needs to be run in self-organized fashions. In this paper, we propose an autonomic <K, D>-interleaving Registry Overlay Network (RgON) that enables web-services' providers/consumers to publish/discover services' advertisements, WSDL documents. The RgON, doubtless empowers consumers to discover web services associated with these advertisements within constant D logical hops over constant K physical hops with reasonable storage and bandwidth utilization as shown through simulation.