16207810
Web Services Methods for Communication over IP
In this paper, we study Web services methods and approaches to enable real-time communication services over IP. This approach extends Web services methodologies from service integration to a service-oriented approach for communication. In particular, we describe the generic Web service based application session management, WS-Session, the two-way full duplex Web service interaction framework, and most importantly, the development of Web service initiation protocol (WIP) which is a full featured Web service and SOA based communication framework for multimedia and voice communication over IP. We show that WIP provides a service oriented architecture which can be extended seamlessly from a P2P endpoint to an endpoint with advanced call control and switching capabilities typically requiring the assistance of a dedicated PBX. A prototype of WIP system is fully developed. Architectural design and system implementation of Web service based communication endpoints are studied and applied to realize service-oriented communication over IP. Advances of WIP indicate the beginning of a full Web service and SOA based communication paradigm that can reshape the converged communication over IP.
11582687
Web service enablement of communication services
In this paper, we introduce Web service application session services, WS-session, for Web service based application session management in communication. A two-way Web service framework is described. It supports the use of Web service in the situation of telecommunication where the communication endpoint can be both a client and a peer-to-peer server. We describe the interface design in two-way Web service interaction based on the concept of tightly coupled interface and loosely coupled interface solutions. The proposed approach provides full support of asynchronous outbound operations and event notifications in communication services. It is implemented in a research prototype system that provides both standard based (ECMA-348) services and Avaya service extensions. In addition, we investigated the integration of our proposed approach with BPEL4WS. It allows the user to create new services through a drag-n-drop based service creation environment (ECLIPSE/BPEL4WS). It leads to a paradigm of service creation through Web service composition. More sophisticated telecommunication services are created from composing the basic services.
14744630
TARGET: Two-way Web Service Router Gateway
In this paper, we present the approach and architecture of TARGET: two-way Web service router gateway, for two-way Web service interaction crossing enterprise domain and firewall. It provides a full support for asynchronous outbound operation and event notification in communication services. TARGET addresses an acute issue for Internet applications that today's enterprise NATs and firewalls only allow outbound HTTP request from the inside to the outside and block any request from the outside to the inside, which is a serious problem for two-way Web services. TARGET is a generic solution to allow two-way Web service interaction to traverse legitimately through NATs and strictly configured firewalls; and it is based on two-way SOAP message tunneling, service local registry, and service routing to bridge two-way Web service interaction. A research TARGET system has been implemented and applied to real time communication services, e.g. conferencing. Extensive experiments on TARGET are performed, and its performance with various sizes of SOAP messages is studied. The applicability and feasibility of TARGET for two-way Web service interaction is verified
29911696
Web Service for Tele-Communication
In this paper, we introduce WNET/WSIP, a web service enabled converged communication infrastructure that is integrated with VoIP SIP (Session Initiation Protocol). WNET/WSIP consists of a network of WSIP node and it is based on two-way, full duplex web service interaction. WSIP is a new class of IP communication endpoints. Each WSIP node is both a SIP endpoint that communicates in the SIP world through SIP signaling, and a web service SOAP node that provides an application protocol layer alternative to SIP and a generic service integration environment for binding SIP based communication in web services. From service perspective, WNET/WSIP is an application layer protocol overlay for resilient and versatile communication services over IP. It allows dynamic service discovery and binding that integrate SIP services as a SOA component in business transactions. It separates service integration/extension environment from SIP signaling. The ubiquitous service integration nature of web service provides a disciplined solution to monitor the WNET/WSIP network. It supports dynamic service monitoring, provisioning, endpoint discovery and update, etc. In particular, we introduce the approach of using WSSecurity [12] to provide end-to-end message level security over IP in WNET/WSIP. These new capabilities are essential to the success of reliable communication services. The proposed approach was implemented in a prototype research system. Advantages of WNET/WSIP were realized and observed.
3230690
A new verification-based fast-match for large vocabulary continuous speech recognition
Acoustic fast-match is a popular way to accelerate the search in large-vocabulary continuous-speech recognition, where an efficient method is used to identify poorly scoring phonemes and discard them from detailed evaluation. In this paper we view acoustic fast-match as a verification problem, and hence develop an efficient likelihood ratio test, similar to other verification scenarios, to perform the fast match. Various aspects of the test like the design of alternate hypothesis models and the setting of phoneme look-ahead durations and decision thresholds are studied, resulting in an efficient implementation. The proposed fast-match is tested in a large vocabulary speech recognition task and it is demonstrated that depending on the decision threshold, it leads to 20-30% improvement in speed without any loss in recognition accuracy. In addition, it significantly outperforms a similar test based on using likelihoods only, which fails, in our setting, to bring any improvement in speed-accuracy trade-off. In a larger set of experiments with varying acoustic and task conditions, similar improvements are observed for the fast-match with the same model and setting. This indicates the robustness of the proposed technique. The gains due to the proposed method are obtained within a highly efficient 2-pass search strategy and similar or even higher gains are expected in other alternative search architectures.
1165057
An Extensible Three-tier XML Dialogue System Architecture for Multimodal Interaction and Automated Agent Services
15977207
Exploiting hierarchical CP-nets to increase the reliability of Web services workflow
Individual Web services can be composed together to form value-added composite Web services represented as business process workflow. However, the value of such composite Web services is directly influenced by the reliability of the composite services. Composing Web services is not an easy task and is error-prone, so there is a growing interest for the verification techniques which enable designers to find and repair design errors even before actual running of the service, or allow designers to detect erroneous properties such as deadlocks or livelocks and formally verify whether the service process design does have certain desired properties (such as consistency with the conversation protocols of partner service). In this paper, we present to analyze and verify Web services composition by using some kind of colored Petri nets (CP-nets) called hierarchical CP-nets, which combine the strengths of Petri nets with the expressive power of high-level programming and have sound mathematical semantics. Services composition proposals can be transformed by transformation rules into CP-nets, which can be simulated to analyze the performance and verified to investigate behavioral properties by exploiting existing CP-nets specialized tools
1036059
Neighbor Relationship and Optimization in Mesh Overlay Multicast
Nodes in mesh overlay multicast system don't have fixed parent-children relationship like that in trees and form neighbors. But in data-driven mesh and based on pulling method, for each packet, it still follows a certain tree and the parent-children relationship does exist. While having the powerful peers stay closer to the source may improve the performance, we make the peers of high out bandwidth preempt the neighbor of the peers near the source. In our paper, we describe the delivery trees set and construct the main distribution tree, which carries most of the data, to construct the signaling path and relay priority preemption message to reduce the cost. We model the neighbor relationship to decide which neighbor to be preempted based on the capacity of the node and the contribution it makes to the probed nodes. Our simulations show that after a temporary reduction in performance at the beginning, which for the optimization chaos of optimization procedure, the system converges to a stable state and gains better performance, especially for playback delay, and meanwhile the control overhead is in reasonable range.
195347610
Environment Lighting for Point Sampled Geometry
13519541
WS-SLA: A Framework for Web Services Oriented Service Level Agreements
Service level agreements (SLA) becomes the prevailing business model for delivery of a large number of products and services in telecommunication and IT arenas. We presents an integrated service level agreement model applied to operating supporting system (OSS), on the basis of WfMC workflow reference model and service oriented architecture (SOA). And an application scenario instance of SLA system architecture is described by a set of operations models by Business Process Execution Language (BPEL)
32348366
Stabilization of switched linear systems with bounded disturbances and unobservable switchings
This paper studies the stabilization problem of switched linear systems with bounded disturbances. It is assumed that the system switches among an infinite set of uniformly controllable linear systems, and that the switching signals are not observable, but the switching duration has a lower bound. It will be shown that by combining on-line adaptive estimation and control in the controller design, a feedback control law can be constructed which makes the switched linear system globally stable.