Request for Comments: 5616

Streaming Internet Messaging Attachments This document describes a method for streaming multimedia attachments received by a resource- and/or network-constrained device from an IMAP server. It allows such clients, which often have limits in storage space and bandwidth, to play video and audio email content. The document describes a profile for making use of the URLAUTHauthorize

A SOAP Web Services-Based Architecture for Floor Control in Multimedia Conferencing

Multimedia conferencing applications are an important and widely-used category of Web applications. Floor control is a significant and advanced feature of multimedia conferencing applications. Floor control mechanisms, when introduced in audio/video conferencing, control the media streams such as identifying which participant is allowed to send and who can be seen or heard. This prevents conflict and ensures an optimized use of resources between the conference participants. Floor control is composed of three logical entities: a single floor control server (i.e. entity responsible for managing the floors and their status), one or more floor chairs (moderators), and any number of regular conference participants. This thesis proposes a SOAP Web services based architecture for floor control in multimedia conferencing. Web services are designed to support interoperable machine-to-machine interaction over a network. They are attractive because of their flexibility. There are two types of web services: SOAP Web services and RESTful Web services. In SOAP Web services, interactions between the entities are based on XML and use SOAP, which is embedded in HTTP. RESTful web services are an architectural design style that rely on HTTP, but do not use SOAP. XML is also optional. We propose a set of floor control requirements and use them to review the related work and pinpoint the weaknesses. The proposed architecture includes the main components of floor control. It also includes a comprehensive set of server-side and client-side SOAP web service APIs that expose the floor control capabilities to application developers. The proposed APIs are programming language-independent and provide a higher level of abstraction to the application developers, which enables the interoperability. Furthermore, in the proposed architecture the floor control clients do not interact directly with the floor control server (FCS) but through a gateway accessible using SOAP web services. This opens up the possibility to use different floor control protocols transparently to the floor control clients. Application portability is no longer a problem because floor clients access the floor capabilities independently of the protocol supported by the FCS. We have built a conferencing application with floor control as a proof of concept to demonstrate the new interface for floor control and the feasibility of the proposed architecture. In addition, performance measurements have also been made to evaluate the viability of the architecture

A criação de redes de próxima geração IMS usando produtos Open Source

Estágio realizado na PT InovaçãoTese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 200

A Virtualized Infrastructure for IVR Applications as Services

Interactive Voice Response (IVR) applications are ubiquitous nowadays. Automated attendant, bank teller and automated surveys are a few of many applications requiring IVR capabilities. Cloud computing is a paradigm gaining a lot of momentum. It has three major service models: Infrastructure as a service – IaaS, Platform as a service – PaaS, and Software as a Service – SaaS. It offers also several inherent benefits such as scalability, resource efficiency and easy introduction of new functionality. However, very few, if any, IVR applications are offered today in cloud-based settings despite of all its potential benefits. This thesis deals with IaaS. Accordingly, we propose a novel architecture for a virtualized IVR infrastructure that relies on RESTFul Web services. The architecture proposes IVR substrates that are virtualized, composed, and assembled on the fly to build IVR applications. As a proof of concept, we have implemented an IaaS prototype on which performance measurements have been done to evaluate our architecture concept. In addition, a simple proof of concept PaaS consisting of a graphical user interface (GUI)has been built to enable the development and management of simple IVR services in the SaaS layer

A study of XML in the library science curriculum in Taiwan and South East Asia

This paper aims to investigate the current XML-related courses available in 96 LIS schools in South East Asia and Taiwan’s 9 LIS schools. Also, this study investigates the linkage of library school graduates in Taiwan who took different levels of XML-related education (that is XML arranged as an individual course or XML arranged as a section unit in courses) and their professional qualification. Research questions include what is the availability of XML-related courses in countries in Taiwan and South East Asia? What are Taiwan LIS graduates’ views on degree of XML-related courses satisfaction, cognition of learning XML technology, and views of XML-related courses? What is the linkage of Taiwan LIS graduates who studied different levels of XML-related education and their professional qualifications? This study applies 3 research methodologies: information gathering from the internet; questionnaire surveys; in-depth interviews. Results of the analysis show that LIS schools should provide optional XML-related courses with practical sessions, and library associations should provide regular XML-related continuing education to enhance LIS students’ professional qualifications

SOAP-Based Web Services vs. RESTful Web Services for Multimedia Conferencing Applications: A Case Study

RESTful web services are now emerging as an alternative that may be more suitable than SOAP-based counterparts in some cases. In this paper, we contrast these two web programmatic interfaces for the development of multimedia conferencing applications, an important category of web applications. A RESTful web service that offers the same functionality as the standard Parlay-X multimedia SOAP-based web service is proposed. The two interfaces are prototyped in the same environment, and the same application is developed using both interfaces. The performance of each are compared and lessons learned are discussed. Fatna Belqasmi, Jagdeep Singh, Suhib Bani melhem, Roch H. Glith

A structural and functional specification of a SCIM for service interaction management and personalisation in the IMS

The Internet Protocol Multimedia Subsystem (IMS) is a component of the 3G mobile network that has been specified by standards development organisations such as the 3GPP (3rd Generation Partnership Project) and ETSI (European Telecommunication Standards Institute). IMS seeks to guarantee that the telecommunication network of the future provides subscribers with seamless access to services across disparate networks. In order to achieve this, it defines a service architecture that hosts application servers that provide subscribers with value added services. Typically, an application server bundles all the functionality it needs to execute the services it delivers, however this view is currently being challenged. It is now thought that services should be synthesised from simple building blocks called service capabilities. This decomposition would facilitate the re-use of service capabilities across multiple services and would support the creation of new services that could not have originally been conceived. The shift from monolithic services to those built from service capabilities poses a challenge to the current service model in IMS. To accommodate this, the 3GPP has defined an entity known as a service capability interaction manager (SCIM) that would be responsible for managing the interactions between service capabilities in order to realise complex services. Some of these interactions could potentially lead to undesirable results, which the SCIM must work to avoid. As an added requirement, it is believed that the network should allow policies to be applied to network services which the SCIM should be responsible for enforcing. At the time of writing, the functional and structural architecture of the SCIM has not yet been standardised. This thesis explores the current serv ice architecture of the IMS in detail. Proposals that address the structure and functions of the SCIM are carefully compared and contrasted. This investigation leads to the presentation of key aspects of the SCIM, and provides solutions that explain how it should interact with service capabilities, manage undesirable interactions and factor user and network operator policies into its execution model. A modified design of the IMS service layer that embeds the SCIM is subsequently presented and described. The design uses existing IMS protocols and requires no change in the behaviour of the standard IMS entities. In order to develop a testbed for experimental verification of the design, the identification of suitable software platforms was required. This thesis presents some of the most popular platforms currently used by developers such as the Open IMS Core and OpenSER, as well as an open source, Java-based, multimedia communication platform called Mobicents. As a precursor to the development of the SCIM, a converged multimedia service is presented that describes how a video streaming application that is leveraged by a web portal was implemented for an IMS testbed using Mobicents components. The Mobicents SIP Servlets container was subsequently used to model an initial prototype of the SCIM, using a mUlti-component telephony service to illustrate the proposed service execution model. The design focuses on SIP-based services only, but should also work for other types of IMS application servers as well

A Cloud Platform-as-a-Service for Multimedia Conferencing Service Provisioning

Multimedia Conferencing is the real-time exchange of media content (e.g. voice, video and text) between multiple participants. It is the basis of a wide range of conferencing applications such as massively multi-player online games and distance learning applications. For faster development as well as cost efficiency, developers of such conferencing applications can use conferencing services (e.g. dial-in audio conference) provided by third-parties. However, the third-party service providers face several challenges with respect to conferencing service provisioning (i.e. service development, deployment and management). One challenge is mastering complex low-level details of conferencing technologies, protocols and their interactions. Another challenge is resource elasticity. Number of conference participants varies during runtime. So resource utilization in an elastic manner is a critical factor to achieve cost efficiency. Cloud Computing can help tackle these challenges. It is a paradigm for swiftly provisioning a shared pool of configurable resources (e.g. services, applications, network and storage) on demand. It has three main service models: Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS). Using a PaaS, service providers can provision conferencing services easily and offer them as SaaS. Nonetheless, cloud-based provisioning of conferencing services still remains a big challenge due to the shortcomings of existing PaaS. In this thesis, a PaaS architecture for conferencing service provisioning is proposed. It is based on a business model from the state of the art. It relies on conferencing IaaSs that, instead of VMs, offer conferencing substrates (e.g. dial-in signaling, video mixer and audio mixer). The conferencing PaaS enables composition of new conferences from substrates on the fly. Moreover, it provides conferencing service providers, who are experienced in programming, with high-level interfaces to abstract the internal complexities of conferencing. In order for PaaS to scale ongoing conferences elastically, an algorithm is also presented in this thesis. The conferencing PaaS is prototyped and performance measurements are made. The proposed algorithm’s performance is also evaluated

Next Generation Emergency Call System with Enhanced Indoor Positioning

The emergency call systems in the United States and elsewhere are undergoing a transition from the PSTN-based legacy system to a new IP-based system. The new system is referred to as the Next Generation 9-1-1 (NG9-1-1) or NG112 system. We have built a prototype NG9-1-1 system which features media convergence and data integration that are unavailable in the current emergency calling system. The most important piece of information in the NG9-1-1 system is the caller's location. The caller's location is used for routing the call to the appropriate call center. The emergency responders use the caller's location to find the caller. Therefore, it is essential to determine the caller's location as precisely as possible to minimize delays in emergency response. Delays in response may result in loss of lives. When a person makes an emergency call outdoors using a mobile phone, the Global Positioning System (GPS) can provide the caller's location accurately. Indoor positioning, however, presents a challenge. GPS does not generally work indoors because satellite signals do not penetrate most buildings. Moreover, there is an important difference between determining location outdoors and indoors. Unlike outdoors, vertical accuracy is very important in indoor positioning because an error of few meters will send emergency responders to a different floor in a building, which may cause a significant delay in reaching the caller. This thesis presents a way to augment our NG9-1-1 prototype system with a new indoor positioning system. The indoor positioning system focuses on improving the accuracy of vertical location. Our goal is to provide floor-level accuracy with minimum infrastructure support. Our approach is to use a user's smartphone to trace her vertical movement inside buildings. We utilize multiple sensors available in today's smartphones to enhance positioning accuracy. This thesis makes three contributions. First, we present a hybrid architecture for floor localization with emergency calls in mind. The architecture combines beacon-based infrastructure and sensor-based dead reckoning, striking a balance between accurately determining a user's location and minimizing the required infrastructure. Second, we present the elevator module for tracking a user's movement in an elevator. The elevator module addresses three core challenges that make it difficult to accurately derive displacement from acceleration. Third, we present the stairway module which determines the number of floors a user has traveled on foot. Unlike previous systems that track users' foot steps, our stairway module uses a novel landing counting technique. Additionally, this thesis presents our work on designing and implementing an NG9-1-1 prototype system. We first demonstrate how emergency calls from various call origination devices are identified, routed to the proper Public Safety Answering Point (PSAP) based on the caller's location, and terminated by the call taker software at the PSAP. We then show how text communications such as Instant Messaging and Short Message Service can be integrated into the NG9-1-1 architecture. We also present GeoPS-PD, a polygon simplification algorithm designed to improve the performance of location-based routing. GeoPS-PD reduces the size of a polygon, which represents the service boundary of a PSAP in the NG9-1-1 system