Yih-Farn Chen

Personalized multimedia services using a mobile service platform

In this paper we address the research issues in providing personalized multimedia services, which enable a mobile user to remotely record video programs, control cameras, and request the delivery of pre-recorded or live video content to his or her own mobile device. We describe a mobile service platform that authenticates users who send service requests from various mobile devices, transcodes video content based on user and device profiles, and authorizes the delivery of content from a media server to the proper client device. The media server adapts automatically to the fluctuations of the wireless channel conditions for reasonable viewing on the client device. The mobile service platform essentially manages the control path, while the media server handles the actual content delivery. We discuss various aspects of the integration and report our successful experiments conducted on wireless LAN and CDPD networks.

iMobile EE: an enterprise mobile service platform

AbstractiMobile is an enterprise mobile service platform that allows resource-limited mobile devices to communicate with each other and to securely access corporate contents and services. The original iMobile architecture consists of devlets that provide protocol interfaces to different mobile devices and infolets that access and transcode information based on device profiles. iMobile Enterprise Edition (iMobile EE) is a redesign of the original iMobile architecture to address the security, scalability, and availability requirements of a large enterprise such as AT&T. iMobile EE incorporates gateways that interact with corporate authentication services, replicated iMobile servers with backend connections to corporate services, a reliable message queue that connects iMobile gateways and servers, and a comprehensive service profile database that governs operations of the mobile service platform. The iMobile EE architecture was also extended to provide personalized multimedia services, allowing mobile users to remotely control, record, and request video contents. iMobile EE aims to provide a scalable, secure, and modular software platform that makes enterprise services easily accessible to a growing list of mobile devices roaming among various wireless networks.

Clicker - An IPTV Remote Control in Your Cell Phone

This paper investigates a novel concept of providing seamless control and portability of an IPTV viewing session. A solution employing a middleware system, a secure hardware token and a cell phone are used to demonstrate how an IPTV session can be securely controlled remotely and moved between multiple viewing stations. We have built a prototype of the system and demonstrated its flexible features. Depending on the users protocol of choice, most remote control operations from a mobile device took less than 5 seconds to execute. An interesting capability of previewing content of other channels via the users device while still continuing to watch the program on the viewing station differentiates it from todays IPTV offers. Finally for mobile content delivery, we address the problem of dynamic device profile selection and content adaptation using a classification algorithm to match the best content alternative destined for a mobile.

MediaAlert - a broadcast video monitoring and alerting system for mobile users

We present a system for automatic monitoring and timely dissemination of multimedia information to a range or mobile information appliances based on each users interest profile. Multimedia processing algorithms detect and isolate relevant video segments from over twenty television broadcast programs based on a collection or words and phrases specified by the user. Content repurposing techniques are then used to convert the information into a form that is suitable for delivery to the users mobile devices. Alerts are sent using a number of application messaging and network access protocols including email, short message service (SMS), multimedia messaging service (MMS), voice, session initiation protocol (SIP), fax, and pager protocols. The system is evaluated with respect to performance and user experiences. The MediaAlert system provides an effective and low-cost solution for the timely generation of alerts containing personal, business, and security information.

VP2P: A Virtual Machine-Based P2P Testbed for VoD Delivery

Recent advances in P2P technology have made it a viable alternative for the delivery of rich media by both content and service providers. However, to better understand and utilize P2P technologies in building a scalable media distribution platform, the nature of the underlying network must be taken into consideration. Although many P2P simulations have been conducted previously, very few were evaluated on a real P2P testbed with the properties of the physical network in mind. In this paper, we describe VP2P, a virtual machine-based P2P testbed, which supports P2P studies with the consideration of typical service provider networks. We use four fully equipped MacPros to emulate 32 peers in the current implementation. Experiments of three P2P algorithms for Video On Demand (VoD) services: BitTorrent, Toast, and Zebra, were run on the testbed. We discuss the rationales behind the hardware and software architecture of VP2P, report our results, and conclude with lessons learned and future directions for VM-based testbeds.

iMobile ME - A Lightweight Mobile Service Platform for Peer-to-Peer Mobile Computing

As mobile devices become increasingly more powerful in storage, computation power, and communication capabilities, we anticipate an emerging need for a mobile device to access information or services on other mobile devices. A mobile device, however, may still be limited by its physical size, battery power, and intermittent communication capabilities. To facilitate information exchanges among these mobile devices, we propose a lightweight service platform on each mobile device and a network-based, always connected proxy that routes requests and responses among these devices. The lightweight platform adopts the notions of devlets and infolets in iMobile Standard Edition (SE), a proxy-based mobile service platform, to provide communication and information access interfaces on each mobile device. We call this lightweight platform iMobile Micro Edition (ME). ME devlets allow the local user and remote devices to communicate with the ME dispatcher through various communication protocols. ME infolets provide access to resources available on the mobile device. The ME dispatcher arbitrates communications among the front-end devlets and the backend infolets. To handle intermittent connections and varying bandwidths, each devlet or infolet with remote access is extended with an inbox queue that accumulates incoming messages and an outbox queue that accumulates outgoing messages — until a synchronization request with the network-based proxy (iMobile SE) is activated. The iMobile SE proxy synchronizes its message queues with those of mobile devices that attempt to communicate with each other. The collaboration of iMobile ME platforms and an SE proxy provides a lightweight infrastructure that enables new peer-to-peer mobile applications to be developed quickly for various mobile devices.

Empowering the battlefield with a mobile middleware platform

In this paper we analyze the utility of mobile middleware platform technology applied in a realistic military exercise scenario. The system was demonstrated to the Office of Naval Research in partial fulfillment of the US Marines Corps next generation ground logistics command and control (GLC2) platform. In particular, we will highlight four mission critical activities, namely a) alerting and notification of information to a wide variety of handheld devices, b) a publish and subscribe interface for mobile devices to an ontology driven knowledge dissemination (ODKD) system via the middleware platform, c) link/Status detection and seamless switchover from a secure wired to a secure wireless (802.11b) infrastructure and d) autonomic sensor data parsing and injection for use in a course of action tool simulator.