StoRHm: a protocol adapter for mapping SOAP based Web Services to RESTful HTTP format

A protocol adapter ideally suited to enable enterprises to gradually transition from SOAP Web Services to RESTful HTTP Web Services without impacting existing clients is presented in this paper. The inherent advantage of such a transition is the visibility of RESTful HTTP messages to Web intermediaries such as caches. In contrast, SOAP messages are opaque, which disables Web intermediaries. While both approaches can use HyperText Transfer Protocol (HTTP) for message transfer, the paradigms contrast sharply. SOAP uses an interface specific approach whereas RESTful HTTP uses a Uniform Interface approach. SOAP marks up its payload with eXtensible Markup Language (XML) whereas in certain situations RESTful HTTP requires no XML. We present the disadvantages of the SOAP approach and outline how the RESTful HTTP approach solves these issues. We present results showing opaque SOAP messages transformed into transparent RESTful HTTP messages. We present StoRHm (SOAP to RESTful HTTP mapping), a protocol adapter which maps SOAP messages to RESTful HTTP format.     

一种高效的Web服务性能优化策略

Web服务是构建面向服务架构(SOA)的主流分布式计算技术.基于XML的数据传输格式在给Web服务带来众多优点的同时,严重影响了其性能,制约了Web服务的应用.众多研究表明,XML解析和数据绑定是Web服务的主要性能瓶颈.着眼于避免传统XML解析和运行时Java反射过程的开销,提出了一种新颖的Web服务性能优化策略.它为每个Web服务生成一个特定于该服务的SOAP消息处理器,通过在对SOAP消息的一遍扫描中高效地生成服务业务逻辑调用所需的参数对象.实验结果表明,该优化策略能够有效地提高Web服务的性能.     

XML语法检查的实现

XML是可扩展标记语言，开发者可根据需要定义合适的标记。由于其灵活性，已被广泛应用于各个领域。主要讨论XML语法检查的两种方法，着重分析其中的一种，并给出具体的实现算法。对XML语法进行检查包括两部分，XML的有效性检查和XML的结构良好性检查，首先对表示XML文档类型定义（DTD）的局部树语法进行改进，然后在DTD构造的语法基础上，对XML进行有效性检查，针对语法检查的两个部分分别构造了检查算法。实验结果表明，该语法检查算法是切实可行的。     

用WSE实现SOAP消息路由

SOAP是WebService的重要技术之一，它以XML形式提供了一个简单轻量的、用于在分散或分布环境中交换结构化和类型化信息的机制。但SOAP规范没有定义标准的路由协议，而只是提供了一个可扩展的框架。WSE为，NET框架开发人员提供了最新的Web服务功能，它支持数字签名、消息路由等。文章详细分析SOAP协议特点、SOAP消息框架、消息处理模型和SOAP的HTTP协议绑定，重点介绍并通过具体实验实现了用WSE进行SOAP消息路由的全过程。WSE为各种规范都提供了很好的支持，它将服务器端的WebMethods和客户端的代理巧妙地结合起来。     

一种基于SOA的SOAP消息安全传输机制

随着SOA技术的发展与普及应用,基于SOA的Web服务安全问题日益突出,而SOAP消息传输的安全性是决定Web服务安全的重要因素。目前SOAP消息的传输主要依赖于WS安全标准,但由于WS安全标准存在种种缺陷,因此SOAP消息在传输过程中会受到XML注入攻击等Web攻击。提出了一种新的SOAP消息安全传输机制,即在现有的基于WS安全标准的安全传输机制基础上添加SOAP Validation节点。最后通过实验验证,该安全传输机制能检测出XML注入攻击,提高SOAP消息传输的安全性。     

基于面向服务架构体系的WEB组合技术应用研究

Web服务是基于XML和HTTPS的一种服务,其通信协议主要基于简单对象访问协议(SOAP),服务的描述通过WSDL、UD-DI来发现和获得服务的元数据。Web服务建好以后,SOAP提供了标准的RPC方法来调用Web service,并意味着下面的Webservice是以对象的方式表示的。SOAP规范定义了SOAP消息的格式,以及怎样通过HTTP协议来使用SOAP。该文基于此,对面向服务架构体系的WEB组合技术应用进行了初步研究。     

基于Web services的XML引擎安全模型研究*

Web services提供软件接口,实现Internet上服务的调用。它以XML为基础,使用了基于XML语言的协议来描述要执行的操作或要与另一个Web服务交换的数据。SOAP是Web services的传输层协议,所有的SOAP消息均使用XML编码。XML engine是建立在Web service上的一种技术。在整个Web服务应用中,XML处于消息层的位置,而XML engine则针对Web服务应用中的XML进行操作,所以称做消息层网关。在XML engine平台上,通过动态共享对象(DSO)机制,将     

XCQ: A queriable XML compression system

XML has already become the de facto standard for specifying and exchanging data on the Web. However, XML is by nature verbose and thus XML documents are usually large in size, a factor that hinders its practical usage, since it substantially increases the costs of storing, processing, and exchanging data. In order to tackle this problem, many XML-specific compression systems, such as XMill, XGrind, XMLPPM, and Millau, have recently been proposed. However, these systems usually suffer from the following two inadequacies: They either sacrifice performance in terms of compression ratio and execution time in order to support a limited range of queries, or perform full decompression prior to processing queries over compressed documents.In this paper, we address the above problems by exploiting the information provided by a Document Type Definition (DTD) associated with an XML document. We show that a DTD is able to facilitate better compression as well as generate more usable compressed data to support querying. We present the architecture of the XCQ, which is a compression and querying tool for handling XML data. XCQ is based on a novel technique we have developed called DTD Tree and SAX Event Stream Parsing (DSP). The documents compressed by XCQ are stored in Partitioned Path-Based Grouping (PPG) data streams, which are equipped with a Block Statistics Signature (BSS) indexing scheme. The indexed PPG data streams support the processing of XML queries that involve selection and aggregation, without the need for full decompression. In order to study the compression performance of XCQ, we carry out comprehensive experiments over a set of XML benchmark datasets. Wilfred Ng obtained his M.Sc.(Distinction) and Ph.D. degrees from the University of London. His research interests are in the areas of databases and information Systems, which include XML data, database query languages, web data management, and data mining. He is now an assistant professor in the Department of Computer Science, the Hong Kong University of Science and Technology (HKUST). Further Information can be found at the following URL: . Wai-Yeung Lam obtained his M.Phil. degree from the Hong Kong University of Science and Technology (HKUST) in 2003. His research thesis was based on the project “XCQ: A Framework for Querying Compressed XML Data.” He is currently working in industry. Peter Wood received his Ph.D. in Computer Science from the University of Toronto in 1989. He has previously studied at the University of Cape Town, South Africa, obtaining a B.Sc. degree in 1977 and an M.Sc. degree in Computer Science in 1982. Currently he is a senior lecturer at Birkbeck and a member of the Information Management and Web Technologies research group. His research interests include database and XML query languages, query optimisation, active and deductive rule languages, and graph algorithms. Mark Levene received his Ph.D. in Computer Science in 1990 from Birkbeck College, University of London, having previously been awarded a B.Sc. in Computer Science from Auckland University, New Zealand in 1982. He is currently professor of Computer Science at Birkbeck College, where he is a member of the Information Management and Web Technologies research group. His main research interests are Web search and navigation, Web data mining and stochastic models for the evolution of the Web. He has published extensively in the areas of database theory and web technologies, and has recently published a book called ‘An Introduction to Search Engines and Web Navigation’.     

使用X509证书签名加密SOAP消息

将Web Services应用于商业开发,安全性能是必须要考以明文字符的方式在服务和客户之间传递,这样很容易造成信息的泄露和被恶意更改.文中介绍了在.NET平台下如何使用X509证书对SOAP消息进行签名和加密的具体方法,并通过具体实例,讲解了如何将一个使用明文SOAP消息的WebServices和客户端改进成使用X509证书进行签名和加密的服务和客户端调用,以达到安全Web Services的目的.     

Redundancy-aware SOAP messages compression and aggregation for enhanced performance

Many organizations around the world have started to adopt Web services as well as server farms and clouds hosted by large enterprise and data centers for various applications. Web Services offer several advantages over other communication technologies. However, they have high latency and often suffer from congestion and bottlenecks due to the massive load generated by web service requests from large numbers of end users. SOAP (Simple Object Access Protocol) is the basic XML-based communication protocol of Web services. XML is a verbose encoding language in comparison with other technologies such CORBA and RMI. In this paper, two new redundancy-aware SOAP Web message aggregation models - Two-bit and One-bit XML status tree - are proposed to enable the Web servers to aggregate SOAP responses and send them back as one compact aggregated message in order to reduce the required bandwidth, latency, and improve the overall performance of Web services. XML message compressibility, the Jaccard based clustering technique, and the vector space model are three similarity measurements that are proposed to cluster SOAP messages as groups based on their similarity degree. The clustering based similarity measurements enable the aggregation techniques to potentially reduce the required network traffic by minimizing the overall size of the messages. The experiments show significant performance for both aggregation techniques achieving compression ratios as high as 25 for aggregated SOAP messages.     

利用Web服务和XML实现数据库同步

XML（可扩展标记语言）以其自描述性和便于传输的优势迅速成为网络上交换数据的存储格式。Web服务的应用使得Web应用程序可以透明地访问服务,请求参数和响应结果是被序列化进入SOAP消息中的。结合Web服务和XML技术的各自特点 ,提出了利用Web服务和XML实现数据库同步的策略。     

基于Web Service代理的业务流程监控

为了能高效地从业务流程中抽取出所需的绩效指标,提出利用Web service代理(WS-Proxy)对基于Web service的业务流程进行监控。WS-Proxy提供单一的服务访问点,实现服务映射、消息转发和数据抽取。在YFilter的基础上开发基于DFA的抽取算法,WS-Proxy可以利用该算法高效地对Web service消息进行检查,对消息中的XML元素内容进行抽取。实验证明,WS-Proxy在处理SOAP消息时比YFilter具有更高的效率。     

移动电子政务平台中安全Web服务的研究

在移动电子政务平台中,使用Webservice是常见的部署方案,web服务是自包含、自描述、模块化的应用,可以通过Web调用它部署的服务,但要求慎重考虑安全性,Web服务使用SOAP协议进行消息传送,SOAP以XML格式在信道中传输,存在信息泄露的风险,传送敏感数据时一定要加密。为解决安全性问题提出一种基于．NET平台的解决方案,使用Web服务时,通过授权的用户经过身份验证可以访问网络信息,客户端在登录时,先获取服务端的公钥,再与服务端协商出用于SOAP消息加密用的非对称密钥与对称密钥,并获取加密后的SessionID,利用SOAP头实现身份验证,利用SOAP扩展实现SOAP消息的选择性加密,使移动电子政务安全性得到保障。     

一种基于AXIS的Web服务安全模型设计及实现

本文讨论了Web服务安全模型和SOAP消息安全框架的核心技术,利用AXIS引擎的处理器可扩展性,按XML数字签名和加密规范建立了SOAP消息安全处理机制,设计了一套基于AXIS的SOAP消息级Web服务安全模型,并且进行了实现。     

异步Web Services的可靠性探讨

Web服务是面向服务的开发模式和Web技术共同发展的结果,采用现有的网络协议如HTTP,FTP或者SMTP作为传输载体,使用基于XML的XML-RPC或者SOAP作为远程调用和消息传输的数据标准.由于其松散的噪成结构,可靠性成了Web服务推广的最大瓶颈.本文通过对异步Web Services的消息类型和事务管理进行了一定的探讨,给出了消息的分类标准和初步的事务模型.     

基于倒排表与B+树的联合索引技术

为提高XML文档的查询效率,提出一种基于倒排表与B+树的联合索引技术。DTD结构索引和内容索引采用倒排表作为索引单位,XML文档索引使用B+树作为索引基本组织。在DTD结构索引的结点编码中设置标识信息,便于确定需要查询的文档。通过建立DTD结构索引、XML文档索引和内容索引,实现混合型XML文档的查询。理论分析与实验结果表明,该技术具有较小的空间开销和较高的查询效率。     

Slicing XML Documents

Program slicing is a well-known technique to extract the program statements that (potentially) affect the values computed at some point of interest. In this work, we introduce a novel slicing method for XML documents. Essentially, given an XML document (which is valid w.r.t. some DTD), we produce a new XML document (a slice) that contains the relevant information in the original XML document according to some criterion. Furthermore, we also output a new DTD such that the computed slice is valid w.r.t. this DTD. A prototype implementation of the XML slicer has been undertaken.     

基于DTD节点自动机的XML模式验证方法

XML已经成为Web环境中数据表示和交换的标准。XML的模式验证在XML的使用中地位重要。DTD作为模式描述的一种方法,应用广泛,但使用DTD描述的模式不能正常表示同构的XML数据。文章扩展了DTD并提出了一种基于自动机的模式验证方法,将扩展的DTD中每个元素转换为一个自动机,将XML文档编码为字符串,并将字符串作为自动机的输入进行验证,可以有效地验证同构的XML。