Global multimedia collaboration system

Global Multimedia Collaboration System Geoffrey Fox1, Wenjun Wu1, Ahmet Uyar2, Hasan Bulut1, Shrideep Pallickara1 gcf@indiana.edu, wewu@indiana.edu, auyar@syr.edu, hbulut@indiana.edu, spallick@indina.edu 1 Community Grids, Pervasive Technology labs, Indiana University 2 Department of Electrical Engineering & Computer Science, Syracuse University Abstract In order to build an integrated collaboration system over heterogeneous collaboration technologies, we propose a Global Multimedia Collaboration System (Global-MMCS) based on XGSP A/V Web-Services framework. This system can integrate multiple A/V services, and support various collaboration clients and communities. Now the prototype is being developed and deployed across many universities in USA and China. Keywords: Collaboration, Web-Services, XGSP, Admire, NaradaBrokering 1. Introduction Collaboration systems enable people in remote framework, which is not as mature as H.323. Since places to communicate and cooperate. And most XML and Web Services provide a very powerful collaboration systems are not designed in the capability approach of an open system and cannot communicate heterogeneous distributed systems, it is a very with each other. It will bring substantial benefits to promising solution to build a general collaboration Internet users if we can build an integrated framework based on XML and Web Services collaboration technology. environment, which combines conferencing, streaming, instant messaging as well as other collaboration applications into meta-dating and constructing In this paper, we propose to develop Global single Multimedia Collaboration System (Global-MMCS) However, based on the XGSP web-services framework [3]. traditional collaboration systems can only provide Global MMCS will integrate various services limited collaboration capabilities to a small group of including videoconferencing, instant messaging and people in a local or private community. They have streaming, features that sometimes can be compared but often technologies the and environments. The paper is organized as follows: In hamper Section 2, the architecture of Global-MMCS is interoperability and functionality. Therefore it is very introduced. Section 3 presents the design and important to create a more general framework to implementation of the prototype system. And we give cover the wide range of collaboration solutions and the conclusion in section 4. allow different users from different communities to 2. Global-MMCS Architecture easy-to-use, intuitive systems implementation make environment. implicit assumptions a for architecture that collaborate. support and multiple videoconferencing heterogeneous collaboration To build an integrated large-scale multimedia The ITU standard package, H.323 [7] defines a collaboration system over heterogeneous network complete framework for videoconferencing over environments, we have to design a scalable ISDN and IP networks. But its data and A/V computing architecture and a flexible software collaboration take different conference control framework. Figure 1 shows such a solution to our mechanism, and is not very scalable. SIP [9] as a Global-MMCS. The Messaging event services competing protocol against H.323 in VoIP is just provide publish-subscribe paradigm for all kinds of beginning to put forward its own conferencing group communications in collaboration applications. And it is implemented in a distributed messaging general architecture, which can integrate all possible broker middleware, which helps to ensure QoS collaboration requirements of various collaboration applications videoconferencing, streaming, IM as well as shared over application. On top of these services, all the services diverse network environments. The Collaboration Web services framework defines a services, for example can be described, implemented and deployed. Figure 1: Global-MMCS Architecture 2.1 Global-MMCS Services general session collaboration framework, which can Videoconferencing services may include different support various kinds of collaboration tools. This collaboration systems, such as H.323, SIP [9] and framework includes two parts: one is XGSP (XML AccessGrid [1] system. Real-Server will be added as based General Session Protocol), which defines a a streaming Web-Service. Global-MMCS has SIP general session protocol in XML. The other is proxies and Jabber servers to provide Instant WSDL-CI (WSDL Collaboration Interface), which Messaging service. We allow users to use multiple gives an interface definition of any collaboration types of clients to access Global-MMCS system, server. XGSP solves the issue of interconnecting the including H.323 terminals, SIP endpoints, MBONE different collaboration tools for the same session. For tools, Real and Windows Media Players. example, we have AccessGrid, H.323 as well as SIP Collaboration pattern usually can be divided into for videoconferencing. In order to make the servers two categories: ad-hoc mode, scheduled mode. and clients from different communities be able to Ad-hoc needs Instant Messenger to provide chat and communicate with each other, it is necessary to define remote presence services. And it can implement very only one session protocol which can be translated into dynamic membership, which is quite suitable for AccessGrid, H.323, SIP messages and vice versa. small group and informal collaborations. Scheduled WSDL-CI is used to describe the functionalities of mode needs meeting calendar to prepare the formal the particular collaboration server. When we try to collaboration. People have to log into some web site integrate the server into Global-MMCS, WSDL-CI or use emails to make reservation of some virtual provides the WSDL information to generate the meeting room, send invitations to other attendee in interface component through which Global MMCS advance. Scheduled mode is better for formal and session server can control this collaboration server large-scale will and add it into current active session. For example, support the hybrid collaboration pattern, which collaborations. Global-MMCS the global session server can schedule a third-party allows users to schedule formal meetings or to create H.323 MCU into the collaboration, if this MCU small group ad-hoc meetings. declares its interface in WSDL-CI, including the 2.2 Web Services Architecture methods The Session Web Service tries to provide a of session establishment, membership and session collaboration control. session There are different directories in Global-MMCS. The first is the directory of user account and media terminal. Unique authenticate valid users and bind the user to his media system across the sites in US and China. In China, we terminal. A user account may also include the have a partner group called Admire [2], also working information of user’s media capability, for example, on videoconferencing systems. Admire group comes the audio terminal that the user wants to use. Also it is from National Software Development Environment important to keep the directory of the active terminal, Lab of Beihang University. Now they are beginning which the participant will use to access the media to deploy the Admire videoconferencing system services. The second is the directory of different across the universities in China. Admire developers communities and collaboration servers. A community will build web-services of Admire system based on should be regarded as autonomous area that has its our framework. Indiana A/V research group will use own collaboration control servers and media servers. these web-services interface to integrate Admire with The community directories will be used to integrate H.323, SIP as well as Real Networks streaming different services from different communities. systems. 2.3 General Messaging (NaradaBrokering) 3.1 Admire Project in China Middleware Admire project has been started in 1999 and applications usually help & We plan to build a Global-MMCS prototype videoconferencing identifications Prototype to Collaboration user 3. Global MMCS Implementation for example finished a prototype system – Admire. The initial aim need group of the early project was to develop a large scale communication. But current Internet cannot support real-time multimedia interaction environment on top group communication very well even with IP of NSCFnet, which allows users distributed in multicast solution which seems to have a long time to different sites of NSCFnet to make distant seminars become ubiquitously available. Therefore messaging and middleware is definitely necessary for group collaboration tools. Now, the prototype system can communication over heterogeneous networks. Since support various collaboration tools and provide a topic-based complete publish-subscribe model defines a scientific collaboration conference through management as multiple well as general API for group communication, it seems to be conference archiving service. Furthermore, it can be a deployed on heterogeneous network environments, very good interface between collaboration applications and messaging middleware. supporting both unicast and multicast communication. NaradaBrokering [4] from the Community Grid By the end of 2002, Admire system has been Labs is adapted as a general event brokering deployed in over 20 sites in NSFCNET, CERNET middleware. supports China, and several sites in Japan and United States. publish-subscribe messaging models with a dynamic Admire system is also interoperable with Access Grid, collection of brokers. And it is able to provide the de facto Internet2 multimedia collaborative services for TCP, UDP, Multicast, SSL and raw RTP environment. clients. For accessing the remote resources behind of 3.2 Global MMCS Prototype System NaradaBrokering a firewall, NaradaBrokering provides the capability Figure 2 shows the architecture of Global-MMCS of the communication through firewalls and proxies. prototype system that we are developing. The XGSP It can operate either in a client-server mode like JMS Web Server, XGSP naming & directory server and or in a completely distributed JXTA-like peer-to-peer XGSP session server implement the web-services mode. By combining these two disparate models, framework NaradaBrokering optimized connection, the XGSP Web Server can invoke performance-functionality trade-offs for different web-services provided by other communities, such as scenarios. Admire and SIP. The XGSP Session Server translates can allow of Global-MMCS. Through SOAP the high-level command from the XGSP Web Server NaradaBrokering server. The distributed sets of into signaling messages of XGSP, and sends these NaradaBrokering nodes take the tasks of routing and signaling messages to the NaradaBrokering servers to forwarding create communities and collaboration clients. a publish/subscribe session Real Servers ( Real Producer, Helix Server) on the events to various XGSP Naming & Directory Server XGSP Web Server SIP Servers (Proxy, Registrar Gateway) iM ac video/audio SQL iM ac iM ac XGSP Session Server H.323 Servers ( Gatekeeper, Gateway ) H.323 Community RTP Proxy SOAP Connection Admire Community RTP Proxy SIP Community Access Grid Community ( Multicast ) Narada Broker Infrstructure RTP Channels Figure 2: Global MMCS Prototype System For different A/V clients, Global-MMCS has as windows media players can use RTSP to connect correspondent servers to accept their signaling the Helix Server and choose the multimedia streams requests and provide various services. The H.323 that they are interested in. Servers including a H.323 Gatekeeper and H.323 The NaradaBrokering servers provide a scalable gateway create a new H.323 administration domain distributed for individual H.323 endpoints, translate H.225 and communications H.245 signaling from these endpoints into XGSP applications. Whenever a new session is activated signaling messages, and redirect their RTP channels across Global-MMCS, the same “topic” will be to the NaradaBrokering servers. The SIP Servers created inside NaradaBrokering system by XGSP including a SIP Proxy, SIP Registrar and SIP Gateway session server. Any RTP client or server who wants to create a similar SIP domain for SIP terminals and join in this session, it can “subscribe” to this topic and perform SIP translation. In addition, the SIP Proxy “publish” its RTP messages through RTP Proxies in and SIP Gateway provide the services of Instant the NaradaBrokering system. After we made some Messaging and Chat room for IM capable clients such optimizations on the message transmission of as Windows Messenger. The Real Servers including a NaradaBrokering messaging in platform these system, A/V it for RTP collaboration shows excellent Real Producer and a Helix Server provide a streaming performance for A/V communication. We have tested service to real-player and windows media player. the performance of NaradaBrokering in the case of Enhanced with customer input plug in, our Real high bandwidth video transmission: A video client Producer can receive RTP audio and video packets sends a video stream to the NaradaBrokering server from network, encode them into Real format and and 400 receivers receive it. 12 of these clients run in submit them to the Helix Server. Real-players as well the same machine as the sender client and the rest of the clients run in another machine. We gather the measurement results. results from only those 12 clients, because if we run The tests we have conducted show that our messaging more clients in that machine, receivers introduce systems outpaces JMF reflector in the performance of delays. This video stream has an average bandwidth delay and jitter. It is good enough to be used for large of 600Kbps. So totally it takes up 240Mbps of scale videoconferencing applications. And one broker network bandwidth. We compare the results of can support more than a thousand audio clients or NaradaBrokering with the performance of a JMF more than 400 hundred video clients at one time reflector program written in Java. Figure 3 shows the providing a very good quality. Average delays/packet for 12 (of the 400 total) video-clients. NaradaBrokering Avg=80.76 ms, JMF Avg=229.23 ms 450 NaradaBrokering-RTP JMF-RTP Delay (Milliseconds) 400 350 300 250 200 150 100 50 0 0 200 400 600 800 1000 1200 Packet Number 1400 1600 1800 2000 Average jitter/packet for 12 (of the 400 total) video clients. NaradaBrokering Avg=13.38 ms, JMF Avg=15.55 ms Jitter (Milliseconds) 25 NaradaBrokering-RTP JMF-RTP 20 15 10 5 0 0 200 400 600 800 1000 1200 Packet Number 1400 1600 1800 2000 Figure 3: Comparison between the performance of NaradaBrokering and JMF Based on these XGSP servers and integrate different collaboration communities into a NaradaBrokering servers, Global-MMCS can support global collaboration platform. not only individual collaboration clients but also 5. Reference collaboration [1] Access Grid, http://www.accessgrid.org communities including AccessGrid, Admire, H.323 and SIP. For each community, we can [2]Admire, define its collaboration web-services using WSDL, and http://www.nlsde.buaa.edu.cn/projects/Admire implement these services based its own framework and [3]Geoffrey Fox, Wenjun Wu, Ahmet Uyar, and Hasan protocol. There are two approaches to build RTP Bulut A Web Services Framework for Collaboration channels between these communities. For Admire and Audio/Videoconferencing, The 2002 International community, the Multiconference in Computer Science and Computer web-services of Admire to notify the address of the Engineering, Internet Computing(IC’02), June 2002, rendezvous point. And Admire responds with its Las Vegas rendezvous point in SOAP reply. After that, both sides [4] Geoffrey C. Fox and Shrideep Pallickara, “The will create RTP agents on this rendezvous. For H.323 Narada Event Brokering System: Overview and and SIP community, in additional to web-services Extensions”, proceedings of the 2002 International commands, they have to rely upon H.323 and SIP Conference on Parallel and Distributed Processing Gatekeeper for signaling procedure, which means their Techniques and Applications (PDPTA'02) RTP agents will be created through H.323 or SIP [5] signaling procedure. We have built web-services of Pallickara,Ahmet Uyar and Wenjun Wu, Integration of HearMe [6], a SIP based Voice-over-IP system. Similar NaradaBrokering and Audio/Video Conferencing as a interface can also be implemented based on other SIP or Web Service, IASTED International Conference on H.323 collaboration systems. Now we are co-operating Communications, Internet, and Information Technology, with November 2002, US Virgin Islands. Admire XGSP Web Server research group to invokes build Admire Hasan Web-services. [6] 4. Related Work and Conclusion http://www.hearme.com, There are some research works on bridging SIP and HearMe Bulut, Geoffrey Audio Fox, conference Shrideep system, [7] International Telecommunication Union, “Packet H.323 [8] [10]. But these projects only deal with based interworking between one kind of A/V endpoint and Recommendation H.323, Geneva, Switzerland, Feb. another one. Columbia University group [8] defines the 1998. transformation of H.323 signaling procedure into SIP [8] Jiann-Min Ho, Jia-Chen Hu, and etc, “A Conference procedure and vice versa, which focus on VoIP service Gateway Supporting Interoperability between SIP and issue. And CMU group only implements a conference H.323”, ACM Multimedia 2001, September, 2001. gateway [10] which connects multiple H.323 terminals [9] J. Rosenberg et al., “SIP: Session Initiation and MBone clients. They don’t have an integrated Protocol”, RFC 3261, Internet Engineering Task Force, web-service framework and distributed event service June 2002, http://www.ietf.org/rfc/rfc3261.txt, middleware for heterogeneous collaborations. [10] K.Singh, H. Schulzrinne, “Interworking between In this paper, we presented the design and multimedia SIP/SDP and H.323”, communication Proceedings systems”, of the 1st implementation of a Global Multimedia Collaboration IP-Telephony Workshop (IP Tel’2000), April, 2000 System. Based on the XGSP framework, this system [11] Steve Graham, Simeon Simeonov, etc, Building can provide the services of videoconferencing, instant Web Services with Java, ISBN0-672-32181-5, Sams messaging and streaming to various clients, and publishing.