Interactive information services control system
    1.
    发明授权
    Interactive information services control system 失效
    互动信息服务控制系统

    公开(公告)号:US5481542A

    公开(公告)日:1996-01-02

    申请号:US149929

    申请日:1993-11-10

    摘要: A digital video, audio and data distribution system which enables a set-top terminal (STT) associated with a customer's television set or other information presentation device to request interactive digital video, audio and data services from a service provider (SP) through the use of control system messages transmitted via a hi-directional signalling path. The requested interactive service is transmitted from the service provider over a portion of the bandwidth of a broadband transmission network which is dedicated to interactive digital services. A Video Session Connection (VSC) is provided for setting up and maintaining interactive sessions between the set-top terminal and a video service provider during the time the interactive programming is provided to the customer. The set-top terminal and service provider establish the Video Session Connection via a two-way signalling path within the bandwidth of the transmission medium into the customer's home. Applications of the system of the invention include "movie on demand" services where the set-top terminal not only requests a movie to be transmitted from the service provider for immediate transmission, but also the bi-directional command channel permits the set-top terminal to control the video presentation by sending commands such as Play, Pause, Fast-Forward and the like to the Service Provider while the movie is being transmitted. Other applications of the invention include on-line data retrieval services, shop at home services and other services which require the use of an interactive connection.

    摘要翻译: 一种数字视频,音频和数据分发系统,其使与客户的电视机或其他信息呈现设备相关联的机顶终端(STT)能够通过使用从服务提供商(SP)请求交互式数字视频,音频和数据服务 经由高频信令路径发送的控制系统消息。 所请求的交互服务是通过专用于交互式数字服务的宽带传输网络的一部分带宽从业务提供商发送的。 提供视频会话连接(VSC),用于在向客户提供交互式节目编排时,在机顶终端和视频服务提供商之间设置和维护交互式会话。 机顶终端和服务提供商通过传输介质的带宽内的双向信令路径建立视频会话连接到客户的家中。 本发明的系统的应用包括“电影点播”服务,其中机顶终端不仅要求从服务提供商发送电影以供立即发送,而且双向命令信道允许机顶终端 通过在电影发送时向服务提供商发送诸如播放,暂停,快进等命令来控制视频呈现。 本发明的其他应用包括在线数据检索服务,家庭服务商店和需要使用交互式连接的其他服务。

    Methods and apparatus for time stamp correction in an asynchronous
transfer mode network
    2.
    发明授权
    Methods and apparatus for time stamp correction in an asynchronous transfer mode network 失效
    在异步传输模式网络中进行时间戳校正的方法和装置

    公开(公告)号:US5467342A

    公开(公告)日:1995-11-14

    申请号:US318124

    申请日:1994-10-05

    摘要: Packets of data, some of which may carry a timestamp value, are transmitted through an Asynchronous Transfer Mode (ATM) network. Prior to transmission, each packet of data is encapsulated in a respective convergence sublayer protocol data unit (CS-PDU) having a header portion and a payload portion. The header portion of each CS-PDU contains a time correction indicator (TCI), which indicates whether the CS-PDU carries a packet of data having a timestamp value that may require correction after the CS-PDU passes through the network, and a time reference correction (TRC) field. Each CS-PDU is then segmented into a plurality of successive segments; a first one of the segments of each CS-PDU contains the CS-PDU header. Each segment is then inserted into the payload section of a respective ATM cell for transmission through the network. At each node in the network, cells are examined to determine if they contain a CS-PDU header. If a cell contains a CS-PDU header, any variable delays imposed upon that cell as it passed through the node are measured and added to the TRC field in the CS-PDU header prior to sending the cell to the next node. At a destination node, the accumulated TRC value may be added to the time stamp value of the packet carried in the CS-PDU in order to compensate for the variable delays imposed upon that packet as the cells carrying the packet traversed the network.

    摘要翻译: 通过异步传输模式(ATM)网络传输数据包,其中一些可能携带时间戳值。 在传输之前,每个数据包被封装在具有报头部分和有效负载部分的相应的汇聚子层协议数据单元(CS-PDU)中。 每个CS-PDU的标题部分包含时间校正指示符(TCI),其指示在CS-PDU通过网络之后,CS-PDU是否携带可能需要校正的时间戳值的数据分组,并且时间 参考校正(TRC)字段。 然后将每个CS-PDU分段成多个连续的段; 每个CS-PDU的段中的第一个包含CS-PDU报头。 然后将每个段插入相应ATM信元的有效载荷部分,以通过网络进行传输。 在网络中的每个节点处,检查小区以确定它们是否包含CS-PDU报头。 如果小区包含CS-PDU报头,则在将该小区通过节点之前施加到该小区的任何可变延迟测量并在将该小区发送到下一个节点之前添加到CS-PDU报头中的TRC字段。 在目的地节点,可以将积累的TRC值加到CS-PDU中承载的分组的时间标记值中,以便补偿在携带分组穿过网络的小区时对该分组施加的可变延迟。

    Method for indicating packet errors in a packet-based multi-hop
communications system
    3.
    发明授权
    Method for indicating packet errors in a packet-based multi-hop communications system 失效
    在基于分组的多跳通信系统中指示分组错误的方法

    公开(公告)号:US5457701A

    公开(公告)日:1995-10-10

    申请号:US177943

    申请日:1994-01-06

    IPC分类号: H04L1/00

    CPC分类号: H04L1/0083

    摘要: A method is disclosed for providing packet error indication in a multi-hop communications system in which packets of data are transmitted from a transmission site to a reception site via a plurality of successive physical links. According to the method, at the transmission site, a pre-defined bit in a packet to be transmitted is set to a first value, the first value indicating that no errors are present in the packet. Then, at each successive physical link in the communication system, after transmission of the packet over that physical link, the following steps are performed: (a) detecting whether any uncorrectable errors occurred in the packet during transmission over that physical link; (b) if an uncorrectable error is detected, setting the pre-defined bit in the packet to a second value wherein the second value is indicative of an uncorrectable error in the data of the packet; and (c) relaying the packet to the next successive physical link for transmission over that next link. A decoder at the reception site may, upon receiving a given packet, examine the value of the pre-defined bit to determined the integrity of the data contained in that packet.

    摘要翻译: 公开了一种用于在多跳通信系统中提供分组错误指示的方法,其中数据分组经由多个连续物理链路从传输站点发送到接收站点。 根据该方法,在发送站点,将要发送的分组中的预定义位设置为第一值,第一值表示分组中不存在错误。 然后,在通信系统中的每个连续的物理链路上,在通过该物理链路传输分组之后,执行以下步骤:(a)在通过该物理链路的传输期间检测在分组中是否发生任何不可校正错误; (b)如果检测到不可校正的错误,则将分组中的预定义位设置为第二值,其中第二值表示分组的数据中的不可校正的错误; 和(c)将分组中继到下一个连续的物理链路,以便在该下一个链路上传输。 在接收站点处的解码器可以在接收到给定的分组时检查预定义比特的值,以确定该分组中包含的数据的完整性。

    Partial Dual-Encryption Using Program Map Tables
    7.
    发明申请
    Partial Dual-Encryption Using Program Map Tables 有权
    使用程序映射表进行部分双加密

    公开(公告)号:US20090147954A1

    公开(公告)日:2009-06-11

    申请号:US12352712

    申请日:2009-01-13

    IPC分类号: H04N7/167 H04L9/00

    摘要: Systems and method for partial encryption are disclosed. One example method comprises: creating a program association table to include a first program number which identifies a program encrypted in accordance with a first encryption scheme, and a second program number which identifies the same program encrypted in accordance with a second encryption scheme; and creating a program map table for the same program to include first audio and video identifiers associated with the first encryption scheme and second audio and video identifiers associated with the second encryption scheme.

    摘要翻译: 公开了用于部分加密的系统和方法。 一个示例性方法包括:创建程序关联表以包括标识根据第一加密方案加密的程序的第一程序号和标识根据第二加密方案加密的相同程序的第二程序号; 以及创建用于相同程序的程序映射表,以包括与第一加密方案相关联的第一音频和视频标识符以及与第二加密方案相关联的第二音频和视频标识符。