Alexander Gelman

Bio: Alexander Gelman is an academic researcher from Telcordia Technologies. The author has contributed to research in topics: Synchronization & Token passing. The author has an hindex of 4, co-authored 5 publications receiving 531 citations.

Communications Architecture and Buffer for Distributing Information Services

Abstract: A store-and-forward architecture which stores and distributes information programs to subscribers includes: information warehouses which archive information programs and dispense information programs in segments to central offices in bursts; central offices which manage subscriber's requests for service and buffer segments of information programs for delivery to subscribers in real-time under the subscriber's interactive control; and customer premises equipment. The central offices employ CO buffers, and each CO buffer includes: processors (402, 405), for administering internal buffer operations and processing subscribers requests based upon the service presentation script and a program presentation map; interfaces (43, 46) for providing external access; busses (411, 412) for internal transport; buffer storage (403, 404) for storing segments of information programs; and memory storage (407, 413) for storing the script and map.

XDSL-based internet access router

Abstract: An Internet Protocol based system (100) and method facilitate communication and improve the network performance between remote user terminals (15) and Web servers (28), that are configured by a communication network, including an asynchronous transfer mode (ATM) network (22). The system includes Local Area Networks (LANs) (12), each comprising a plurality of user terminals (15). The system further comprises at least one network switch (22), and at least one digital subscriber line (xDSL) multiplexor and access router (120), each connected between a corresponding LAN and the network switch. Thus, each user communicates directly with its default router obviating the requirement of communicating via the network switch to the default IP edge routers (126). Further, where Quality of Service is required, the xDSL access router serves as the default router for the Web server. XDSL access router helps to reduce the processing load on the Internet edge routers.

Scheduling transmission multimedia information in broadband networks using a token passing scheme

Abstract: A scheduling system and method, which employ a token passing scheme, for scheduling transmission of multimedia information between information warehouses (IWHs) and CO clusters (CCs) interconnected by ATM switch(es). Each CO cluster employs a CC schedule processor, which has means for receiving and means for storing requests for multimedia information, means for sorting and prioritizing the requests, means for forwarding requests to appropriate IWHs, and means for accepting or rejecting tokens offered by IWHs in response to a request. The IWH employs an IWH schedule processor which includes means for receiving and means for storing requests from CO clusters, means for selecting a request and generating a token to be sent to the CO cluster originating the request, and means for storing a list of CO cluster rejecting tokens. Requests received from multiple subscribers are stored, sorted, and prioritized at CC schedule processors, which forward the requests to appropriate IWHs. The schedule processor of each IWH receives and stores requests from CO clusters, selects a request to be serviced based on a first distance function and issues a token to the CO cluster originating the selected request. The CC schedule processor of each CO cluster selects a token to be accepted based upon a second distance function, and the requested multimedia information is transmitted from the IWH issuing the token to the CO cluster. Other tokens are rejected and returned to the issuing IWH. Each IWH may maintain a list of CO cluster rejecting its issued tokens.

A Path Reservation Protocol For An ATM/PVC-Based Video Retrieval Network

Abstract: A protocol to connect clusters of customers to Information Providers, via an ATM Virtual Path Crossconnect is presented. The traffic consists of bursts of cells at the peak rate of the carrier. The delivery of these bursts is subject to deadlines which are imposed by applications and are necessary to preserve the temporal properties of the information (e. g. video). An ongoing dialog between the clusters and the information providers must guarantee synchronization to achieve maximal throughput. We present a protocol which achieves fast synchronization even at high loads, for systems where the traffic patterns change slowly, such as video-on-demand systems. The protocol is distributed, in the sense that clusters do not talk among themselves, and likewise the information providers do not communicate among themselves. We examine what happens when customers change their requests from time to time. For example a customer watching a video might request a ‘fast forward’ or ‘rewind’. Some analytical results are obtained for this case, and verified by simulation. We check by simulation if the protocol can be implemented in real time, without serious degradation to the throughput. Finally we present an experimental formula to calculate the deadline miss rate.

Network controller for cable television delivery systems

Abstract: A novel network controller for use with a digital cable headend capable of monitoring and controlling set top terminals in a television program delivery system is described. The invention relates to methods and apparatus for a network controller that manages a configuration of set top terminals in a program delivery system. The invention is particularly useful in program delivery systems with hundreds of channels of programming, a menu driven program selection system, and a program control information signal that carries data and identifies available program choices. Specifically, the invention modifies a program control information signal at the cable headend before the modified signal is transmitted to each set top terminal. This signal is used with polling methods to receive upstream data from the set top terminals. The invention initiates such upstream data retrieval, gathers all data received and compiles viewer demographics information and programs watched information. The invention processes this data and information to generate packages of advertisements, as well as account and billing reports, targeted towards each set top terminal. The invention uses upstream data reception hardware, databases and processing hardware and software to accomplish these functions.

Audio and video transmission and receiving system

Abstract: A system of distributing video and/or audio information employs digital signal processing to achieve high rates of data compression. The compressed and encoded audio and/or video information is sent over standard telephone, cable or satellite broadcast channels to a receiver specified by a subscriber of the service, preferably in less than real time, for later playback and optional recording on standard audio and/or video tape.

System and method for delivery of video data over a computer network

Abstract: A video clip storage and retrieval system whereby video clips, stored locally and/or at a more remote location, can be requested and retrieved by a user at the user's multimedia terminal. When the user requests a desired video clip, the request is processed by a primary index manager ("PIM") via a Local Search and Retrieval Unit ("SRU"). Before the message is communicated to the PIM, the local SRU checks its own storage to see whether the requested video clips are available locally. If some of the video clips are local, the local SRU still forwards the request to the PIM so that the PIM may determine specific video clip usage. The PIM determines the extended SRU where the audio-visual data is stored and passes this information to a Data Sequencing Interface ("DSI"). The DSI collects the video clips and downloads the clips to the user's terminal. The user may then view, copy, or print the video clip as desired. In a preferred embodiment, a distributed digital video clip delivery system, according to the invention, provides video clips stored at local and/or remote locations, which can be requested from the Internet and retrieved at the user's multimedia terminal. When the user requests a desired video clip shown on a Web page, the request is diverted to a primary index manager ("PIM"). The PIM attempts to locate the closest server containing the requested clip, from which the download is completed. The system further includes means for uploading and distributing clips to geographically diverse servers, dynamic load balancing, subscription management mechanisms, and protection means to discourage unauthorized duplication of video clips.

Universal access multimedia data network

Abstract: A system and method for providing Internet access via a Public Switched Telecommunications Network (PSTN) using full time asymmetric digital subscriber line connections between subscriber premises processor terminals and a local area network (LAN) node and router gateway on Telco premises connected to a Telco digital packet network connected to Internet service providers and Internet information providers. A domain name server (DNS) and a dynamic host configuration protocol (DHCP) server are connected to the router to provide domain name to IP address translations and temporary assignment of IP addresses to said customer premises processor terminal. The customer or subscriber going on-line communicates with the DHCP using encryption and preferably public/private key encryption to both authenticate the customer and the DHCP. The DHCP updates the database in the DNS to maintain freshness. The digital packets in the network use several protocols with a TCP/IP payload encapsulated therein without the need for translation or conversion.

Digital information library and delivery system with logic for generating files targeting a playback device

Abstract: A computer network based digital information library system employing authentication and encryption protocols for the secure transfer of digital information library programs to a client computer system and a mobile digital information playback device removably connectable to the client computer system. The present invention is a computer network based library and information delivery system for accessing and obtaining selected digital information files. The library and information delivery system comprises: 1) a library server having a plurality of digital information files; 2) a client computer system coupled to the library server over a network; and 3) a mobile device removably connectable to the client computer system, the client computer system including logic for requesting a download of a selected one or more of the digital information files from the library server, the client computer system further including logic for downloading the selected one or more of the digital information files to the mobile device.