CN101095331A - System and method for selecting a multicast IP address - Google Patents

Abstract

The disclosed embodiments relate to a system and method for selecting a multicast IP address. More specifically, there is provided a method comprising: selecting a first IP address from a plurality of IP addresses; performing a hash calculation on the first IP address to create a first hash value corresponding to the first IP address; determining whether the first hash value corresponds to a second IP address being used; and assigning the first IP address if the first hash value does not correspond to the second IP address being used.

Description

Translated fromChinese

用于选择组播IP地址的系统和方法System and method for selecting a multicast IP address

技术领域technical field

本发明大体上涉及在网络上发送视频或其它数字数据。更具体地，本发明涉及一种选择用于在互联网协议(“IP”)网络上组播视频、音频或其它数据的组播组(multicast group)的系统。The present invention generally relates to sending video or other digital data over a network. More specifically, the present invention relates to a system for selecting a multicast group for multicasting video, audio or other data over an Internet Protocol ("IP") network.

背景技术Background technique

该章节意欲向读者介绍与下面描述和/或要求保护的本发明的多个方面有关的各种现有技术。相信该讨论有助于给读者提供背景技术以便于更好地理解本发明的多个方面。因此，应该理解到，要从这种角度阅读这些陈述，而不应该将其作为现有技术的陈述。This section is intended to introduce the reader to various prior art that may be related to various aspects of the present invention that are described and/or claimed below. It is believed that this discussion helps to provide the reader with a background in which to better understand aspects of the invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

在过去几年里，大多数人们认识到，诸如DirecTV的卫星电视系统越来越普遍。实际上，由于1994年DirecTV的引入，一千两百多万美国家庭开始成为卫星电视订户。这些订户中的多数独门独户地居住在相对容易安装和连接圆盘式卫星电视天线的地方。例如，圆盘式卫星电视天线可安装在屋顶上。Over the past few years, most people realize that satellite TV systems such as DirecTV have become more common. In fact, since the introduction of DirecTV in 1994, more than 12 million American households have become satellite TV subscribers. Many of these subscribers live alone where it is relatively easy to install and connect a satellite dish. For example, a satellite TV dish can be mounted on a roof.

然而，很多潜在的订户居住或暂时居住在多住户单元(“MDU”)中，例如旅馆或高层公寓大楼。不幸的是，给MDU内的各个居住单元提供卫星电视服务会涉及到额外的挑战。给每个住户提供并连接一个圆盘式卫星电视天线是不切实际的，并且/或者是极其昂贵的。例如，在拥有一千个公寓的高层公寓大楼中，在大楼楼顶安装一千个圆盘式卫星电视天线是不切实际的。一些传统的系统通过将数字卫星电视信号转换为可通过单根同轴电缆传送到多个住户的模拟信号，避免了这些问题。然而，这些系统提供有限的信道，与全数字系统相比，质量下降，并且无法提供独门独户居住的用户所习惯的卫星电视体验。However, many potential subscribers live or temporarily live in multi-dwelling units ("MDUs"), such as hotels or high-rise apartment buildings. Unfortunately, providing satellite television service to individual living units within an MDU involves additional challenges. It is impractical and/or prohibitively expensive to provide and connect a satellite television dish to each household. For example, in a high-rise apartment building with a thousand apartments, it is impractical to install a thousand satellite TV dishes on the roof of the building. Some traditional systems avoid these problems by converting the digital satellite TV signal to an analog signal that can be sent to multiple households over a single coaxial cable. However, these systems offer limited channels, reduced quality compared to all-digital systems, and do not provide the satellite TV experience that single-family users are accustomed to.

需要一种改进的系统和/或方法，用于给多住户单元提供卫星电视。What is needed is an improved system and/or method for providing satellite television to multi-dwelling units.

发明内容Contents of the invention

下面提出在范围上与最初要求保护的本发明相符合的某些方面。应该理解，这些方面仅提出用于给读者提供本发明也许呈现的某些形式的简要说明，并且这些方面并不意欲限制本发明的范围。实际上，本发明可包括下面未给出的多个方面。Certain aspects commensurate in scope with the originally claimed invention are presented below. It should be understood that these aspects are presented merely to provide the reader with a brief description of some forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may include various aspects not presented below.

所公开的实施例涉及用于选择组播IP地址的系统和方法。更具体地，提供了一种方法，包括：从多个IP地址中选择第一IP地址；对第一IP地址进行散列(hash)计算以创建与第一IP地址相对应的第一散列值；确定第一散列值是否与正在使用的第二IP地址相对应；以及如果第一散列值与正在使用的第二IP地址相对应，则分配第一IP地址。The disclosed embodiments relate to systems and methods for selecting a multicast IP address. More specifically, a method is provided, comprising: selecting a first IP address from a plurality of IP addresses; performing a hash calculation on the first IP address to create a first hash corresponding to the first IP address value; determining whether the first hash value corresponds to the second IP address in use; and assigning the first IP address if the first hash value corresponds to the second IP address in use.

附图说明Description of drawings

在结合附图阅读下面详细的说明时，本发明的优点将变得显而易见，附图中：Advantages of the present invention will become apparent when the following detailed description is read in conjunction with the accompanying drawings, in which:

图1是根据本发明一个实施例的示范性的卫星IP电视系统的框图；1 is a block diagram of an exemplary satellite IP television system according to one embodiment of the present invention;

图2是本发明的图1所示的示范性的卫星IP电视系统的另一实施例；Fig. 2 is another embodiment of the exemplary satellite IP television system shown in Fig. 1 of the present invention;

图3是本发明的示范性卫星网关的框图；以及Figure 3 is a block diagram of an exemplary satellite gateway of the present invention; and

图4是示出了根据本发明实施例的用于选择组播IP地址的示范性技术方案的流程图。Fig. 4 is a flowchart showing an exemplary technical solution for selecting a multicast IP address according to an embodiment of the present invention.

具体实施方式Detailed ways

下面将描述本发明的一个或多个特定实施例。为了提供这些实施例的简要描述，在说明书中未描述实际实施方式的所有特征。应该认识到，如在任意工程或设计项目中一样，在任何实际实施方式的开发中，必须作出多个实施方式特定决策，以实现开发者的特定目的，例如与系统有关和商业有关的限制的兼容性，而这对于不同实施方式是不同的。此外，应该认识到，这种开发也许是复杂且耗时的，但是对于受益于本公开的普通技术人员而言，是设计、制作和制造的例行工作。One or more specific embodiments of the invention are described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be recognized that, as in any engineering or design project, in the development of any actual implementation, a number of implementation-specific decisions must be made to achieve the developer's specific objectives, such as constraints related to the system and business Compatibility, which is different for different implementations. Furthermore, it should be appreciated that such development might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

转向图1，附图标记10大体上表示并示出了根据一个实施例的示范性的卫星IP电视系统的框图。如图所示，在一个实施例中，系统10可包括一个或多个圆盘式卫星电视天线12a至12m、例如卫星网关14的头端(head-end)单元、IP分发网络(IP distribution network)20以及一个或多个机顶盒(“STB”)22a至22n。然而，本领域的普通技术人员可认识到，图1所示的系统10的实施例仅仅是系统10的一个可能实施例。同样地，在可选实施例中，可重新设置或省略系统10的所示组件，或者可将附加组件添加到系统10。例如，在微小的修改的情况下，可将系统10配置为分布式的非卫星视频和音频服务。Turning to FIG. 1 ,reference numeral 10 generally designates and illustrates a block diagram of an exemplary satellite IP television system according to one embodiment. As shown, in one embodiment,system 10 may include one ormore satellite dishes 12a through 12m, a head-end unit such assatellite gateway 14, an IP distribution network ) 20 and one or more set-top boxes ("STB") 22a to 22n. However, one of ordinary skill in the art will recognize that the embodiment ofsystem 10 shown in FIG. 1 is only one possible embodiment ofsystem 10 . Likewise, illustrated components ofsystem 10 may be rearranged or omitted, or additional components may be added tosystem 10, in alternative embodiments. For example, with minor modifications,system 10 could be configured for distributed non-satellite video and audio services.

圆盘式卫星电视天线12a-12m可配置为接收视频、音频或从环绕地球的卫星发送的与电视有关的其它类型数据。在下面将描述，在一个实施例中，圆盘式卫星电视天线12a-12m配置用于接收在从10.7至12.75千兆赫兹(“GHz”)的KU波段上编制的DirecTV。然而，在可选实施例中，圆盘式卫星电视天线12a-12m可配置用于接收其它类型的直播卫星(“DBS”)或电视单收站(“TVRO”)信号，例如Dish网络信号、ExpressVu信号、StarChoice信号等。在其它不基于卫星的系统中，系统10中可省略圆盘式卫星电视天线12a-12m。Satellite television dishes 12a-12m may be configured to receive video, audio, or other types of television-related data transmitted from satellites orbiting the earth. As will be described below, in one embodiment,satellite dishes 12a-12m are configured to receive DirecTV programmed on the KU band from 10.7 to 12.75 gigahertz ("GHz"). However, in alternative embodiments, thesatellite dishes 12a-12m may be configured to receive other types of Direct Broadcast Satellite ("DBS") or Television Reception Only ("TVRO") signals, such as Dish Network signals, ExpressVu signal, StarChoice signal, etc. In other non-satellite based systems,satellite dishes 12a-12m may be omitted fromsystem 10.

在一个实施例中，圆盘式卫星电视天线12a-12m中的低噪声块(“LNB”)从绕地卫星接收输入信号，并将这些输入信号转换为950和2150兆赫兹(“MHz”)的L波段的频率。下面结合图2将进一步详细描述，卫星12a-12m中的每一个可配置用于接收在特定频率上并具有特定极化的一个或多个输入卫星电视信号(称为应答器(transponder))，并且用于将这些卫星信号转换为L波段信号，每一个L波段信号可包含多个视频或音频信号。In one embodiment, the low noise blocks ("LNBs") in thesatellite dishes 12a-12m receive input signals from orbiting satellites and convert these input signals to 950 and 2150 megahertz ("MHz") the frequency of the L-band. As will be described in further detail below in conjunction with FIG. 2, each of thesatellites 12a-12m may be configured to receive one or more incoming satellite television signals (referred to as transponders) on a particular frequency and having a particular polarization, And it is used to convert these satellite signals into L-band signals, and each L-band signal can contain multiple video or audio signals.

如图1所示，圆盘式卫星电视天线12a-12m可配置用于将L波段信号发送到头端单元或网关服务器，例如卫星网关14。在可选的非卫星实施例中，头端单元可以是有线电视接收机、高清晰电视接收机或其它视频分发系统。As shown in FIG. 1 ,satellite dishes 12a - 12m may be configured to transmit L-band signals to a headend unit or gateway server, such assatellite gateway 14 . In alternative non-satellite embodiments, the headend unit may be a cable television receiver, high definition television receiver, or other video distribution system.

卫星网关14包括卫星调谐、解调和解复用模块16以及IP包装器(wrapper)模块18。模块16可包括多个调谐器、解调器和解复用器，以将从卫星12a-12m发送来的经调制和复用的L波段信号转换为多个单一节目传输流(“SPTS”)，每一个SPTS均载有服务(例如电视频道的视频、电视频道的音频、节目指南等)。在一个实施例中，模块16配置用于针对圆盘式卫星电视天线12a-12m所接收的所有服务，产生单一节目传输流。然而，在可选实施例中，模块16可仅针对圆盘式卫星电视天线12a-12m所接收的服务的子集，产生传输流。Thesatellite gateway 14 includes a satellite tuning, demodulation anddemultiplexing module 16 and anIP wrapper module 18 .Module 16 may include a plurality of tuners, demodulators and demultiplexers to convert the modulated and multiplexed L-band signals transmitted fromsatellites 12a-12m into a plurality of Single Program Transport Streams ("SPTS"), Each SPTS carries services (eg, video of a TV channel, audio of a TV channel, program guide, etc.). In one embodiment,module 16 is configured to generate a single program transport stream for all services received bysatellite dishes 12a-12m. However, in alternative embodiments,module 16 may generate transport streams for only a subset of the services received bysatellite dishes 12a-12m.

卫星调谐、解调和解复用模块16可将SPTS发送到IP包装器模块18。在一个实施例中，IP包装器模块18将SPTS中的数据重新分组为适合在IP分发网络20上传输的多个互联网协议(“IP”)分组。例如，IP包装器模块18可将SPTS中的DirectTV协议分组转换为IP分组。此外，IP包装器18可配置用于从STB 22a-22n接收服务器请求，并将IP SPTS组播(即，通过IP地址向一个或多个STB 22a-22n广播)到请求特定服务的这些STB 22a-22n。The satellite tuner, demodulation anddemultiplexer module 16 may send the SPTS to theIP wrapper module 18 . In one embodiment,IP wrapper module 18 repackets the data in the SPTS into a plurality of Internet Protocol (“IP”) packets suitable for transmission overIP distribution network 20 . For example,IP wrapper module 18 may convert DirectTV protocol packets in SPTS to IP packets. Additionally,IP wrapper 18 may be configured to receive server requests fromSTBs 22a-22n and to multicast (i.e., broadcast by IP address to one ormore STBs 22a-22n) IP SPTS to thoseSTBs 22a requesting a particular service -22n.

在可选实施例中，IP包装器模块18还可配置用于组播STB22a-22n之一未请求的服务的IP协议SPTS。应该注意，模块16和18仅仅是卫星网关14的一个示范性实施例。在可选实施例中，例如下面结合图2和3所述的实施例，模块16和18的功能可以在多种适当的组件或模块中重新分配或组合。In an alternative embodiment, theIP wrapper module 18 may also configure the IP protocol SPTS for multicasting services not requested by one of the STBs 22a-22n. It should be noted thatmodules 16 and 18 are merely one exemplary embodiment ofsatellite gateway 14 . In alternative embodiments, such as the embodiment described below in conjunction with FIGS. 2 and 3 , the functionality ofmodules 16 and 18 may be redistributed or combined among various suitable components or modules.

IP分发网络20可包括一个或多个路由器、开关、调制解调器、分裂器或桥。例如，在一个实施例中，卫星网关14可与主配线架(distribution frame，“MDF”)相连，MDF与中间配线架(“IDF”)相连，IDF与以太网桥的同轴电缆相连，以太网桥与路由器相连，路由器与STB 22a-22n中的一个或多个相连。在另一实施例中，IP分发网络20可以是与数字用户线接入复用器(“DSLAM”)相连的MDF，DSLAM与DSL调制解调器相连，DSL调制解调器与路由器相连。在另一实施例中，IP分发网络可包括无线网络，例如802.11或WiMax网络。在这种实施例中，STB 2a-22n可包括配置用于接收组播IP地址的无线接收机。本领域普通技术人员可认识到，上述实施例仅仅是示范性的。同样，在可选实施例中，可在系统10中采用大量适当形式的IP分发网络。IP distribution network 20 may include one or more routers, switches, modems, splitters or bridges. For example, in one embodiment, thesatellite gateway 14 may be connected to a main distribution frame ("MDF") which is connected to an intermediate distribution frame ("IDF") which is connected to the coaxial cable of the Ethernet bridge , the Ethernet bridge is connected to the router, and the router is connected to one or more of theSTBs 22a-22n. In another embodiment, theIP distribution network 20 may be an MDF connected to a digital subscriber line access multiplexer ("DSLAM") connected to a DSL modem connected to a router. In another embodiment, the IP distribution network may include a wireless network, such as an 802.11 or WiMax network. In such embodiments, STBs 2a-22n may include wireless receivers configured to receive multicast IP addresses. Those of ordinary skill in the art will recognize that the above-described embodiments are exemplary only. Likewise, a number of suitable forms of IP distribution networks may be employed insystem 10 in alternative embodiments.

IP分发网络20可以与一个或多个STB 22a-22n相连。STB 22a-22n可以是任意适当类型的能够在IP分发网络20上接收例如IP SPTS的IP分组的视频、音频或其它数据接收机。可以认识到，这里使用的术语机顶盒(“STB”)不仅可包括位于电视机上的设备。而是，STB22a-22n可以是在电视机、显示器或计算机内部或外部的任意设备或装置，在此描述为可配置为包括但不局限于视频组件、计算机、无线电话或其它形式的视频记录器。在一个实施例中，STB 22a-22n可以是配置用于通过(其它输入中的)以太网端口来接收例如视频和/或音频的服务的DirectTV接收机。在可选实施例中，STB 22a-22n可以设计和/或配置用于接收同轴电缆、双绞线、铜线上的组播传输，或者经由例如IEEE 802.11标准的无线标准的无线传输。IP distribution network 20 may be connected to one ormore STBs 22a-22n. TheSTBs 22a-22n may be any suitable type of video, audio or other data receiver capable of receiving IP packets such as IP SPTS over theIP distribution network 20. It will be appreciated that the term set top box ("STB") as used herein may not only include devices located on televisions. Rather, theSTBs 22a-22n may be any device or device, internal or external to a television, monitor, or computer, described herein as being configurable to include, but not limited to, a video component, computer, wireless telephone, or other form of video recorder . In one embodiment, theSTBs 22a-22n may be DirectTV receivers configured to receive services such as video and/or audio through Ethernet ports (among other inputs). In alternative embodiments, theSTBs 22a-22n may be designed and/or configured to receive multicast transmissions over coaxial cable, twisted pair, copper wire, or wireless transmissions via a wireless standard such as the IEEE 802.11 standard.

如上所述，系统10可接收卫星在空间发送的视频、音频和/或其它数据，并且处理/转换该数据以便在IP分发网络20上分发。因此，图2是根据一个实施例的示范性的卫星IP电视系统10的另一实施例。图2示出了三个示范性的圆盘式卫星电视天线12a-12c。每一个圆盘式卫星电视天线12a-12c可配置用于接收来自一个或多个绕地卫星的信号。本领域的普通技术人员可认识到，通常以卫星所在的轨道槽(orbital slot)来提及卫星和从卫星发送来的信号。例如，圆盘式卫星电视天线12a配置用于接收来自位于101度的轨道槽的DirecTV卫星的信号。类似地，圆盘式卫星电视天线12b接收来自位于119度的卫星的信号，圆盘式卫星电视天线12c接收来自位于110度的轨道槽的卫星的信号。可以认识到，在可选实施例中，圆盘式卫星电视天线12a-12c可接收来自位于例如95度轨道槽的多个轨道槽的多个其它卫星的信号。此外，圆盘式卫星电视天线12a-12c还可以配置用于接收极化的卫星信号。例如，在图2中，圆盘式卫星电视天线12a配置用于接收左极化(图中示出为“101L”)和右极化(示出为“101R”)的信号。As described above,system 10 may receive video, audio and/or other data transmitted in space by satellites and process/convert the data for distribution overIP distribution network 20 . Accordingly, FIG. 2 is another embodiment of an exemplary satelliteIP television system 10 according to one embodiment. Figure 2 shows three exemplarysatellite television dishes 12a-12c. Eachsatellite dish 12a-12c may be configured to receive signals from one or more satellites orbiting the Earth. Those of ordinary skill in the art will recognize that satellites and signals transmitted from satellites are often referred to in terms of the orbital slots in which the satellites are located. For example,satellite dish 12a is configured to receive a signal from a DirecTV satellite located in an orbital slot of 101 degrees. Similarly,satellite dish 12b receives a signal from a satellite located at 119 degrees, andsatellite dish 12c receives a signal from a satellite located in an orbital slot at 110 degrees. It will be appreciated that, in alternative embodiments, thesatellite dishes 12a-12c may receive signals from a plurality of other satellites located in a plurality of orbital slots, for example 95 degree orbital slots. Additionally, thesatellite dishes 12a-12c may also be configured to receive polarized satellite signals. For example, in FIG. 2,satellite dish 12a is configured to receive signals of left polarization (shown as "101L" in the figure) and right polarization (shown as "101R").

如上面结合图1所述的，圆盘式卫星电视天线12a-12c可接收KU波段的卫星信号，并将这些信号转换为要发送到卫星网关14的L波段信号。然而，在一些实施例中，可在到达卫星网关14之前，将圆盘式卫星电视天线12a-12c所产生的L波段信号合并为更少的信号或分裂为更多的信号。例如，如图2所示，可通过开关24将来自圆盘式卫星电视天线12b和12c的L波段信号合并为单个L波段信号，该单个L波段信号包含来自110度的卫星和119度的卫星的L波段信号。As described above in connection with FIG. 1 ,satellite dishes 12 a - 12 c receive KU-band satellite signals and convert these signals to L-band signals for transmission tosatellite gateway 14 . However, in some embodiments, the L-band signals generated by thesatellite dishes 12a - 12c may be combined into fewer signals or split into more signals before reaching thesatellite gateway 14 . For example, as shown in FIG. 2, the L-band signals from thesatellite dishes 12b and 12c may be combined viaswitch 24 into a single L-band signal containing satellites from 110 degrees and 119 degrees. the L-band signal.

如图所示，系统10还可包括多个1∶2分裂器26a、26b、26c和26d，用于将从圆盘式卫星电视天线12a-12c发送来的L波段信号分为两个L波段信号，每个L波段信号包括分裂前的L波段信号的服务的一半。在可选实施例中，1∶2分裂器26a-26b可省略或集成到卫星网关14a和14b中。As shown, thesystem 10 may also include a plurality of 1:2splitters 26a, 26b, 26c, and 26d for splitting the L-band signal transmitted from thesatellite dishes 12a-12c into two L-band signals, each L-band signal comprises half of the service of the L-band signal before splitting. In alternative embodiments, the 1:2splitters 26a-26b may be omitted or integrated into thesatellite gateways 14a and 14b.

可将新分裂的L波段信号从1∶2分裂器26a-26d发送到卫星网关14a和14b。图2所示的系统10的实施例包括两个卫星网关14a和14b。然而，在可选实施例中，系统10可包括任意适当数目的卫星网关14。例如，在一个实施例中，系统可包括三个卫星网关14。The newly split L-band signals may be sent from 1:2splitters 26a-26d tosatellite gateways 14a and 14b. The embodiment ofsystem 10 shown in FIG. 2 includes twosatellite gateways 14a and 14b. However, in alternative embodiments,system 10 may include any suitable number ofsatellite gateways 14 . For example, in one embodiment, the system may include threesatellite gateways 14 .

卫星网关14a和14b还可进一步细分L波段信号，然后调谐到L波段信号上的一个或多个服务，以产生可重新分组为IP分组并在IP分发网络20上组播的一个或多个SPTS。此外，一个或多个卫星网关14a、14b还可与公共交换电话网络(“PSTN”)28相连。由于卫星网关14a、b与PSTN 28相连，所以STB 22a-22n可通过IP分发网络20和卫星网关14a、b，与卫星服务提供商进行通信。该功能有利地消除了对于将各个单独STB22a-22n直接与PSTN 28相连的需要。Thesatellite gateways 14a and 14b can further subdivide the L-band signal and then tune to one or more services on the L-band signal to produce one or more services that can be repackaged into IP packets and multicast on theIP distribution network 20. SPTS. Additionally, one ormore satellite gateways 14a, 14b may also be connected to a public switched telephone network ("PSTN") 28 . Since thesatellite gateways 14a, b are connected to thePSTN 28, theSTBs 22a-22n can communicate with satellite service providers through theIP distribution network 20 and thesatellite gateways 14a, b. This function advantageously eliminates the need for connecting eachindividual STB 22a-22n directly to thePSTN 28.

IP分发网络20还可与互联网服务提供商(“ISP”)30相连。在一个实施例中，IP分发网络20可以用于给STB 22a-22n和/或与IP分发网络20相连的其它适当的设备(未示出)提供互联网服务，例如高速数据接入。TheIP distribution network 20 may also be connected to an Internet Service Provider (“ISP”) 30 . In one embodiment,IP distribution network 20 may be used to provide Internet services, such as high-speed data access, toSTBs 22a-22n and/or other suitable devices (not shown) connected toIP distribution network 20.

如上所述，卫星网关14a、b可以配置用于接收多个L波段信号，以产生多个SPTS，并在IP分发网络20上组播所请求的SPTS。现在参照图3，图3示出了示范性的卫星网关14的框图。如图所示，卫星网关14a、b包括电源40、两个前端41a和41b以及后端52。电源40可以是多个工业标准AC或DC电源中的任意一个，可配置用于使前端41a、b和后端52能够执行下面所述功能。As mentioned above, thesatellite gateways 14a, b may be configured to receive multiple L-band signals, to generate multiple SPTSs, and to multicast the requested SPTSs over theIP distribution network 20 . Referring now to FIG. 3 , a block diagram of anexemplary satellite gateway 14 is shown. As shown, thesatellite gateways 14a,b include apower supply 40 , twofront ends 41a and 41b and aback end 52 . Thepower supply 40 may be any of a number of industry standard AC or DC power supplies, configurable to enable thefront end 41a, b andback end 52 to perform the functions described below.

卫星网关14a、b还可包括两个前端41a、b。在一个实施例中，每一个前端41a、b均可配置用于接收来自参考图2所述的1∶2分裂器26a-26d的两个L波段信号输入。例如，前端41a可接收来自1∶2分裂器26a的两个L波段信号，前端41b可接收来自1∶2分裂器26b的两个L波段信号。在一个实施例中，输入前端41a、b的每一个L波段均包括八个或更少的服务。Thesatellite gateways 14a,b may also include twofront ends 41a,b. In one embodiment, eachfront end 41a, b is configurable to receive two L-band signal inputs from the 1:2splitters 26a-26d described with reference to FIG. For example, thefront end 41a can receive two L-band signals from the 1:2splitter 26a, and the front end 41b can receive two L-band signals from the 1:2splitter 26b. In one embodiment, each L-band of the input front ends 41a, b includes eight or fewer services.

前端41a、b然后可使用1∶4 L波段分裂器42a、42b、42c和42d来进一步细分L波段输入。一旦细分了，则L波段信号可通过进入双调谐器链路的四个组(bank)44a、44b、44c和44d。组44a-44d中每个双调谐器链路均可配置用于调谐到由单独的双调谐器链路接收的L波段信号内的两个服务，以产生SPTS。每个双调谐器链路然后可将SPTS发送到低压差分信号(“LVDS”)驱动器48a、48b、48c和48d之一。LVDS驱动器48a-48d可配置用于放大L波段传输信号以发送到后端52。在可选实施例中，代替LVDS驱动器48a-48d，可采用不同形式的差分驱动器和/或放大器。其它实施例可采用将所有传输信号串行化，以一并路由到后端52。The front ends 41a, b may then use 1:4 L-band splitters 42a, 42b, 42c and 42d to further subdivide the L-band input. Once subdivided, the L-band signal may pass into fourbanks 44a, 44b, 44c and 44d of the dual tuner chain. Each dual-tuner link ingroups 44a-44d is configurable to tune to two services within the L-band signal received by the individual dual-tuner link to generate SPTS. Each dual tuner link may then send the SPTS to one of low voltage differential signaling ("LVDS")drivers 48a, 48b, 48c, and 48d. LVDS drivers 48 a - 48 d may be configured to amplify L-band transmission signals for transmission tobackend 52 . In alternative embodiments, instead of LVDS drivers 48a-48d, different forms of differential drivers and/or amplifiers may be used. Other embodiments may employ serialization of all transmission signals to be routed to thebackend 52 together.

如图所示，前端41a、b还可包括微处理器46a和46b。在一个实施例中，微处理器46a、46b可控制和/或中继命令到双调谐器链路的组44a-44d和1∶4L波段分裂器42a-42d。微处理器46a、b可包括采用ST微电子技术生产的ST10微处理器。微处理器46a、b可与LVDS接收机和发送机模块50a和50b相连。LVDS接收机/发送机模块50a、b可方便微处理器46a、b与后端52上的组件之间的通信，如下面所述。As shown, thefront ends 41a, b may also includemicroprocessors 46a and 46b. In one embodiment, themicroprocessors 46a, 46b may control and/or relay commands to thesets 44a-44d of the dual tuner chain and the 1:4 L-band splitters 42a-42d. Microprocessors 46a,b may comprise ST10 microprocessors produced by ST Microelectronics. Microprocessors 46a, b may be connected to LVDS receiver andtransmitter modules 50a and 50b. The LVDS receiver/transmitter modules 50a, b may facilitate communication between the microprocessors 46a, b and components on thebackend 52, as described below.

接下来转向后端52，后端52包括LVDS接收机54a、54b、54c和54d，LVDS接收机54a、54b、54c和54d配置用于接收LVDS驱动器48a-48d所发送的传输流信号。后端52还包括LVDS接收机/发送机模块56a和56b，LVDS接收机/发送机模块56a和56b配置用于与LVDS接收机/发送机模块50a、b进行通信。Turning next tobackend 52,backend 52 includesLVDS receivers 54a, 54b, 54c, and 54d configured to receive transport stream signals sent by LVDS drivers 48a-48d.Backend 52 also includes LVDS receiver/transmitter modules 56a and 56b configured to communicate with LVDS receiver/transmitter modules 50a, b.

如图所示，LVDS接收机54a-54d和LVDS接收机/发送机56a、b配置用于与传输处理器58a和58b进行通信。在一个实施例中，传输处理器58a、b配置用于接收在前端41a、b中由双调谐器链路所产生的SPTS。例如，在一个实施例中，传输处理器58a、58b可配置用于产生16个SPTS。传输处理器58a、b可配置用于将SPTS重新分组为可在IP分发网络20上组播的IP分组。例如，传输处理器58a、b可将DirecTV协议分组重新分组为IP协议分组，然后在IP地址上将这些IP分组组播到一个或多个STB 22a-22n。As shown,LVDS receivers 54a-54d and LVDS receiver/transmitters 56a, b are configured to communicate withtransport processors 58a and 58b. In one embodiment, thetransport processors 58a,b are configured to receive SPTS generated by the dual tuner link in thefront end 41a,b. For example, in one embodiment,transport processors 58a, 58b may be configured to generate 16 SPTS. Thetransport processors 58a, b may be configured to repacketize the SPTS into IP packets that may be multicast on theIP distribution network 20 . For example,transport processors 58a, b may repacket DirecTV protocol packets into IP protocol packets, and then multicast these IP packets to one ormore STBs 22a-22n on IP addresses.

传输处理器58a、b还可以与例如32位、66Mz外围组件互联(“PCI”)总线的总线62相连。通过总线62，传输处理器58a、b可以与网络处理器70、以太网接口84和/或扩展槽66进行通信。网络处理70可配置用于接收来自STB 22a-22n的针对服务的请求，并命令传输处理器58a、b组播所请求的服务。在一个实施例中，网络处理器是intel生产的IXP425网络处理器。尽管未示出，网络处理器70还可以配置用于将状态数据发送到卫星网关14a、b的面板(front panel)，或通过调试端口来支持对卫星网关14a、b的调试或监视。Thetransport processors 58a, b may also be connected to abus 62, such as a 32-bit, 66 Mz Peripheral Component Interconnect ("PCI") bus. Throughbus 62 ,transport processors 58 a , b may communicate withnetwork processor 70 , Ethernet interface 84 and/orexpansion slot 66 .Network processing 70 may be configured to receive requests for services fromSTBs 22a-22n and instructtransport processors 58a, b to multicast the requested services. In one embodiment, the network processor is an IXP425 network processor produced by Intel. Although not shown, thenetwork processor 70 may also be configured to send status data to the front panel of thesatellite gateway 14a, b, or to support debugging or monitoring of thesatellite gateway 14a, b through a debug port.

如图所示，传输处理器58a、b还可经由总线62与以太网接口68相连。在一个实施例中，以太网接口68是提供面向IP分发网络20的铜线或光纤接口的吉比特以太网接口。此外，总线62还可与例如PCI扩展槽的扩展槽相连，以便能够升级或扩展卫星网关14a、b。Thetransport processors 58a, b are also connected to anEthernet interface 68 via abus 62, as shown. In one embodiment,Ethernet interface 68 is a Gigabit Ethernet interface providing a copper or fiber optic interface toIP distribution network 20 . In addition, thebus 62 can also be connected to expansion slots, such as PCI expansion slots, so that thesatellite gateways 14a, b can be upgraded or expanded.

传输处理器58a、b还可与周线(host bus)64相连。在一个实施例中，周线64是将传输处理器58a、b连接到调制解调器72的16比特数据总线，其中调制解调器72可配置用于通过如上所述的PSTN 28进行通信。在可选实施例中，调制解调器72还可与总线62相连。Thetransport processors 58a,b are also connected to ahost bus 64. In one embodiment, thecontour 64 is a 16-bit data bus connecting thetransport processors 58a, b to amodem 72, which is configurable for communication over thePSTN 28 as described above. In an alternative embodiment, amodem 72 may also be connected to thebus 62 .

如上所述，卫星网关14可配置用于接收例如电视视频、音频或其它数据的服务，并通过IP分发网络20将这些服务组播到STB 22a-22n。在一个实施例中，STB 22a-22n采用以太网集成电路(“IC”)，针对STB22a-22n中每特定一个所感兴趣的组播，监控IP分发网络20。换言之，在STB 22a-22n的每一个中的以太网IC可针对为发送STB 22a-22n中每一个正使用的那些服务而正在使用的IP地址上的传输，监控IP分发网络20。例如，卫星网关14可将服务组播到一个IP地址上的第一组STB，并将第二服务组播到第二IP地址上的第二组STB。在该示例中，第一组STB内的以太网IC可针对第一IP地址上的活动来监控IP分发网络20，并且第二组STB内的以太网IC可针对第二IP地址上的活动进行监控。以太网IC可通过将输入分组的IP地址与正被监控的IP地址进行比较，来针对特定IP地址上的活动进行监控。As noted above,satellite gateway 14 may be configured to receive services such as television video, audio, or other data and to multicast these services overIP distribution network 20 toSTBs 22a-22n. In one embodiment,STBs 22a-22n employ Ethernet integrated circuits ("ICs") to monitorIP distribution network 20 for multicasts of interest to each particular one ofSTBs 22a-22n. In other words, the Ethernet ICs in each of theSTBs 22a-22n can monitor theIP distribution network 20 for transmissions on the IP addresses being used to deliver those services each of theSTBs 22a-22n are using. For example,satellite gateway 14 may multicast a service to a first set of STBs at one IP address, and multicast a second service to a second set of STBs at a second IP address. In this example, Ethernet ICs within a first set of STBs can monitorIP distribution network 20 for activity on a first IP address, and Ethernet ICs within a second set of STBs can monitorIP distribution network 20 for activity at a second IP address. monitor. The Ethernet IC can monitor for activity on a specific IP address by comparing the IP address of an incoming packet with the IP address being monitored.

然而，典型地，为了降低以太网IC的计算复杂度，对IP地址进行散列计算，缩减为更简单的数，以简化该比较。例如，32比特的IP地址可经过散列计算缩减为6比特的值。然而，本领域的普通技术人员将认识到，32比特的IP地址提供了上百万个不重复的标识值，而6比特的值仅提供了64个唯一值，这些唯一值可称为散列表元(hashbucket)。因此，尽管对IP地址进行散列计算降低了以太网IC的复杂度，但是会在系统10内引入额外挑战。例如，如果两个不相关的组播组采用经散列计算变为相同的6比特值的IP地址，则针对这些IP地址之一而进行监控的STB将对于两个地址都中断。这些不需要的中断会导致STB 22a-22n上的视频和/或音频的回放不连贯或失真。由此，希望降低组播组中的散列冲突。Typically, however, to reduce the computational complexity of the Ethernet IC, the IP address is hashed, reduced to a simpler number, to simplify the comparison. For example, a 32-bit IP address can be hashed down to a 6-bit value. However, those of ordinary skill in the art will recognize that a 32-bit IP address provides millions of unique identification values, while a 6-bit value provides only 64 unique values, which may be referred to as a hash table Yuan (hashbucket). Therefore, while hashing the IP address reduces the complexity of the Ethernet IC, it introduces additional challenges within thesystem 10 . For example, if two unrelated multicast groups employ IP addresses that hash to the same 6-bit value, a STB monitoring for one of these IP addresses will break for both addresses. These unwanted interruptions can cause choppy or distorted playback of video and/or audio on theSTBs 22a-22n. Thus, it is desirable to reduce hash collisions in multicast groups.

因此，图4是示出了根据一个实施例用于选择组播IP地址的示范性技术方案80的流程图。技术方案80可由卫星网关14执行。如下面进一步所述，技术方案80可方便卫星网关14对均匀分布在可用的多个散列表元中的组播IP地址进行选择。例如，技术方案80可在每个散列表元中选择一个组播IP地址，直到每一个散列表元均具有一个IP地址为止，然后在每个散列表元中选择不多于两个IP地址，直到存在与每个散列表元相对应的两个IP地址，如此等等。Therefore, FIG. 4 is a flowchart illustrating an exemplary technical solution 80 for selecting a multicast IP address according to one embodiment. The technical solution 80 can be executed by thesatellite gateway 14 . As further described below, the technical solution 80 can facilitate thesatellite gateway 14 to select the multicast IP addresses evenly distributed among the available multiple hash buckets. For example, technical solution 80 may select a multicast IP address in each hash bucket until each hash bucket has an IP address, and then select no more than two IP addresses in each hash bucket, Until there are two IP addresses corresponding to each bucket, and so on.

如图所示，技术方案80开始于设置等于1的计数器变量MaxBucketCount，将数组HashBuchetCount清零，并将剩余组播地址池重置。MaxBucketCount可指示由卫星网关14允许的散列计算到相同散列表元的IP地址的最大数目。HashBuchetCount数组可包含针对每个HashCount的位置(例如对于6比特的散列值，64个空间)。HashBuchetCount数组可存储当前分配的与每个散列表元相对应的组播IP地址的数目。例如，如果卫星网关14分配了与散列表元1和6相对应的IP地址，则数组位置1和6的每个将包含数1。剩余组播地址池可以是IP地址列表，其中如下面所述，所述IP地址是(1)当前未用于组播卫星服务的IP地址，和(2)暂时未从组播IP地址池中去除的IP地址。As shown in the figure, the technical solution 80 starts with setting the counter variable MaxBucketCount equal to 1, clearing the array HashBuchetCount, and resetting the remaining multicast address pools. MaxBucketCount may indicate the maximum number of IP addresses allowed bysatellite gateway 14 to be hashed to the same bucket. The HashBuchetCount array may contain a location for each HashCount (eg, 64 spaces for a 6-bit hash value). The HashBuchetCount array can store the number of currently allocated multicast IP addresses corresponding to each hash bucket. For example, ifsatellite gateway 14 was assigned IP addresses corresponding to hashbuckets 1 and 6, array positions 1 and 6 would each contain thenumber 1. The remaining multicast address pool may be a list of IP addresses, wherein, as described below, the IP addresses are (1) IP addresses not currently used for multicast satellite service, and (2) temporarily not selected from the multicast IP address pool Removed IP address.

接下来，如块84所示，卫星网关14可等待来自STB 22a-22n之一的服务请求。一旦接收到服务请求，则如块86所示，卫星网关14可确定在组播地址池中是否剩余有组播地址。如果在组播地址池中剩余有组播IP地址，则如块88所示，卫星网关14可选择剩余IP地址之一，并如块90所示，设置等于所选散列表元号的变量n。然后如块92所示，卫星网关14可检查HashBuchetCount数组，以确定存储在HashBuchetCount数组的位置n中的值是否超过MaxBucketCount。例如，如果MaxBucketCount为1，则卫星网关14确定与所选IP地址相对应的HashBuchetCount数组位置是否小于1(即等于0)。Next, as shown in block 84, thesatellite gateway 14 may wait for a service request from one of theSTBs 22a-22n. Once the service request is received, as indicated at block 86, thesatellite gateway 14 may determine whether there are multicast addresses remaining in the pool of multicast addresses. If there are multicast IP addresses remaining in the multicast address pool, then as shown in block 88,satellite gateway 14 may select one of the remaining IP addresses and, as shown in block 90, set the variable n equal to the selected hash bucket number .Satellite gateway 14 may then check the HashBuchetCount array to determine whether the value stored in position n of the HashBuchetCount array exceeds MaxBucketCount, as indicated by block 92 . For example, if MaxBucketCount is 1, thesatellite gateway 14 determines whether the HashBuchetCount array position corresponding to the selected IP address is less than 1 (ie equal to 0).

如果与剩余组播地址相关联的散列表元相对应的HashBuchetCount数组内的位置不小于MaxBucketCount，则如块94所示，卫星网关14可从剩余组播地址池中去除所选组播地址。在从剩余组播地址池中去除所选组播IP地址之后，如图4所示，技术方案80可循环回到块86。以这种方式，卫星网关14可继续检查剩余组播地址池中的组播IP地址，直到发现与HashBuchetCount数组中值小于MaxBucketCount的位置相对应的组播IP地址为止，或者直到从组播地址池中去除所有剩余组播IP地址为止。If the position within the HashBuchetCount array corresponding to the hash buckets associated with the remaining multicast addresses is not less than MaxBucketCount, then as shown at block 94, thesatellite gateway 14 may remove the selected multicast address from the pool of remaining multicast addresses. After removing the selected multicast IP address from the pool of remaining multicast addresses, as shown in FIG. 4 , technical solution 80 may loop back to block 86 . In this way, thesatellite gateway 14 can continue to check the multicast IP addresses in the remaining multicast address pool until the multicast IP address corresponding to the position where the value in the HashBuchetCount array is found to be less than MaxBucketCount is found, or until the multicast IP address is selected from the multicast address pool. until all remaining multicast IP addresses are removed.

回到块92，如果与所选IP地址的散列值相对应的HashBuchetCount数组的值小于MaxBucketCount，则如块96所示，卫星网关14可分配所选组播地址，并在与所选组播地址的HashBucket相对应的位置处使HashBuchetCount数组递增。在使HashBuchetCount数组递增之后，技术方案80可循环回到块84，并等待来自STB 22a-22n之一的另一个服务请求。Returning to block 92, if the value of the HashBuchetCount array corresponding to the hash value of the selected IP address is less than MaxBucketCount, then as shown in block 96, thesatellite gateway 14 may assign the selected multicast address and communicate with the selected multicast address Increment the HashBuchetCount array at the position corresponding to the HashBucket of the address. After incrementing the HashBuchetCount array, technical solution 80 can loop back to block 84 and wait for another service request from one ofSTBs 22a-22n.

如上所述，卫星网关14可循环回到块86，直到其分配了一个组播IP地址为止，或者直到从剩余组播地址池中去除了所有IP地址为止。一旦从组播地址池中去除了所有组播地址，则技术方案80可使MaxBucketCount变量递增(这使得再将一个IP地址分配给每一个散列表元)，并且重置剩余组播地址池，以包含当前未由卫星网关14使用的所有组播地址。在重置剩余组播地址池之后，如上所述，技术方案80可返回到块86。以这种方式，技术方案80通过每个表元分配一个IP地址，直到所有散列表元具有一个IP地址，或者剩余组播地址池中没有可用IP地址为止，方便了在散列表元中平均分配IP地址。As described above, thesatellite gateway 14 may loop back to block 86 until it is assigned a multicast IP address, or until all IP addresses are removed from the pool of remaining multicast addresses. Once all multicast addresses are removed from the multicast address pool, technical solution 80 can increase the MaxBucketCount variable (this makes an IP address be assigned to each hash bucket), and reset the remaining multicast address pool to Contains all multicast addresses not currently in use by thesatellite gateway 14 . After resetting the remaining multicast address pools, technical solution 80 may return to block 86 as described above. In this way, the technical solution 80 allocates an IP address by each bucket until all the buckets have an IP address, or there is no available IP address in the remaining multicast address pool, which facilitates even distribution among the buckets IP address.

可以容易地对本发明进行多种修改并采用多种可选形式，同时附图中举例示出了特定实施例，并在此对其进行了详细描述。然而，应该理解，本发明并不意欲受限于所公开的特定形式。而是，本发明覆盖落入由所附权利要求限定的本发明精神和范围内的所有修改、等同物和可选物。While the invention can readily be modified in many ways and in alternative forms, specific embodiments are illustrated in the drawings and described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention covers all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Claims (20)

1. method comprises:

From a plurality of IP address, select an IP address;

Hash is carried out in the one IP address to be calculated to create and corresponding first hashed value in an IP address;

Determine whether first hashed value is corresponding with the 2nd IP address of using; And

If first hashed value is not corresponding with the 2nd IP address of using, then distribute an IP address.

2. method according to claim 1 wherein, is carried out hash to an IP address and is calculated and to comprise an IP address is calculated as 6 bit values from 32 bit value hash.

3. method according to claim 1 comprises: if first hashed value is not corresponding with the 2nd IP address of using, then use an IP address that satellite service is multicast to set-top box (22).

4. method according to claim 3 wherein, determines whether to use the 2nd IP address to comprise: to determine whether to use the 2nd IP address multicast satellite services.

5. method according to claim 3 comprises: receive the request at satellite service from set-top box (22).

6. method according to claim 3, wherein, multicast satellite services comprises: multicast DirecTV service.

7. method according to claim 1 comprises:

If first hashed value is corresponding with the 2nd IP address of using, then select the 3rd IP address; And

Hash is carried out in the 3rd IP address to be calculated to create second hashed value.

8. a head-end unit (14), configuration is used for:

From a plurality of IP address, select an IP address;

Hash is carried out in the one IP address to be calculated to create and corresponding first hashed value in an IP address;

Determine whether first hashed value is corresponding with the 2nd IP address of using; And

If first hashed value is not corresponding with the 2nd IP address of using, then distribute an IP address.

9. head-end unit according to claim 8 (14), wherein, satellite gateway (14) configuration is used for an IP address is calculated as 6 bit values from 32 bit value hash.

10. head-end unit according to claim 8 (14), wherein, satellite gateway (14) configuration is used for: if first hashed value is not corresponding with the 2nd IP address of using, then use an IP address that satellite service is multicast to set-top box (22).

11. head-end unit according to claim 10 (14), wherein, satellite gateway (14) configuration is used to determine whether using the 2nd IP address multicast satellite services.

12. head-end unit according to claim 10 (14), wherein, satellite gateway (14) configuration is used for receiving the request at satellite service from set-top box (22).

13. head-end unit according to claim 10 (14), wherein, satellite gateway (14) configuration is used for multicast DirecTV service.

14. head-end unit according to claim 8 (14), wherein, satellite gateway (14) configuration is used for:

If first hashed value is corresponding with the 2nd IP address of using, then select the 3rd IP address; And

Hash is carried out in the 3rd IP address to be calculated to create second hashed value.

15. a head-end unit (14) comprising:

Be used for selecting the device of an IP address from a plurality of IP address;

Being used for that hash is carried out in an IP address calculates with the device of establishment with corresponding first hashed value in an IP address;

Be used for determining first hashed value whether with the corresponding device in the 2nd IP address that is using; And

Be used for when first hashed value is not corresponding with the 2nd IP address of using, distributing the device of an IP address.

16. head-end unit according to claim 15 (14) wherein, is carried out hash to an IP address and is calculated and to comprise an IP address is calculated as 6 bit values from 32 bit value hash.

17. head-end unit according to claim 15 (14) comprising: be used for when first hashed value is not corresponding with the 2nd IP address of using, using an IP address satellite service to be multicast to the device of set-top box (22).

18. head-end unit according to claim 17 (14) wherein, is used to determine whether to use the device of the 2nd IP address to comprise: the device that is used to determine whether to use the 2nd IP address multicast satellite services.

19. head-end unit according to claim 17 (14) comprising: be used for receiving device at the request of satellite service from set-top box (22).

20. head-end unit according to claim 17 (14) comprising:

Be used for when first hashed value is corresponding with the 2nd IP address of using, selecting the device of the 3rd IP address; And

Being used for that hash is carried out in the 3rd IP address calculates to create the device of second hashed value.

Images