System for just-in-time retrieval of multimedia files over computer
networks by transmitting data packets at transmission rate determined
by frame size
    4.
    发明授权
    System for just-in-time retrieval of multimedia files over computer networks by transmitting data packets at transmission rate determined by frame size 失效
    通过以帧大小确定的传输速率传输数据包,通过计算机网络即时检索多媒体文件的系统

    公开(公告)号:US5822524A

    公开(公告)日:1998-10-13

    申请号:US505488

    申请日:1995-07-21

    摘要: A method in computer networks in which a client machine (playback client computer) requests multimedia files, such as compressed video clips, from a server (storage server computer). The transmission uses digital data packets. In the case of video files, the packet headers identify the video frame and the sequence number of each packet derived from the frame. The transmission timing is not based on a steady byte stream or an average of bytes to be transmitted. Instead, in the case of video, the frame rate determines normal transmission and a frame is transmitted during each frame time. The client agent has a normal packet buffer, normally holding 1-5 video frames. The transmission rate is adjusted to keep that buffer filled within its normal range. The timing information required for transmission, in one embodiment, is stored in a separate index file associated with each multimedia file.

    摘要翻译: 计算机网络中的方法,其中客户机(回放客户端计算机)从服务器(存储服务器计算机)请求诸如压缩视频剪辑的多媒体文件。 传输使用数字数据包。 在视频文件的情况下,分组标题标识从帧导出的每个分组的视频帧和序列号。 发送定时不是基于稳定的字节流或要发送的字节的平均值。 相反,在视频的情况下,帧速率确定正常传输,并且在每个帧时间期间发送帧。 客户端代理具有正常的分组缓冲区,通常保持1-5个视频帧。 调整传输速率以保持缓冲区在其正常范围内。 在一个实施例中,传输所需的定时信息被存储在与每个多媒体文件相关联的单独的索引文件中。

    Adaptive data link protocol
    5.
    发明授权
    Adaptive data link protocol 失效
    自适应数据链路协议

    公开(公告)号:US4970714A

    公开(公告)日:1990-11-13

    申请号:US294086

    申请日:1989-01-05

    摘要: A communication system provides high speed transmission of data over a link, such as a fiber optic link, between a first terminal and a second terminal. The architecture and protocol permits the use of dedicated hardware such as state machines constructed of programmable array logic units, to synchronize the transmission and reception of data packets and the retransmission of designated ones of these packets in the event of a faulty transmission. Packets to be transmitted and received are stored in an array of frames in sub-windows of a memory storage window in each of the termianls, the frame number being equal to the sequence number of the data packet. By embedding sequence and status bits in each packet within control words and bits appended to each packet, the state machine in each terminal can readily track the progress of each packet so as to request acknowledgement of error-free receipt, to send an acknowledgement, to request a retransmission of a packet designated by its serial number and to distinguish a retransmitted packet from an original packet transmitted with error.