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Unit 9 IPTV,Text IPTV Overview,Unit 9,原文： IPTV is an IP network application that supports several high quality video and audio standards (for example, MPEG and H.261) for live video, scheduled video, and video on demand.,譯文:IPTV 是IP網絡的應用，它為視頻直播、預約視頻、視頻點播提供多種高質量的視頻和音頻標準（例如MGEG 和H.261）支持。,Unit 9,原文： Generally speaking, IPTV refers to the distribution of television and video signals in parallel with the Internet connection supplied by a broadband operator using the same IP (and mostly the same VoIP ) packet network infrastructure. 譯文:一般來說，IPTV是指互聯(lián)網連接的并行電視和視頻信號的分配是由寬帶運營商提供的。他們使用相同的IP（大多是相同的VoIP）數據包和網絡基礎設施,Unit 9,原文：The users can receive and view the contents on a home TV, a PC, or even with a hand-held device on the move. The devices are loaded with an IPTV client. 譯文:用戶可以從家里的電視、PC機甚至是移動的終端上接收和觀看電子菜單。這設備需要從IPTV的機頂盒中下載（電子菜單）。,Unit 9,原文：Content servers house the title collections and the feeds from content producers. The TV contents are usually encoded in a standard format. 譯文:電子菜單的服務是從節(jié)目的制造商那取材并收集節(jié)目的標題，電視的節(jié)目表則常常是以一種特定的格式來編碼的。,Unit 9,原文：The contents can be broadcast or on demand distribution, all controlled by the schedule server. 譯文:電子菜單可以是廣播的，也可以是按照一定的服務表格控制的按需發(fā)送。,Unit 9,原文：The IPTV server handles user requests and the flows are chopped into a stream of IP packets. 譯文:IPTV服務負責用戶的請求并將該信號轉變?yōu)镮P數據包的數字流,Unit 9,原文：The IP packets flow through a core IP network. Unlike a vice stream that only requires 64 kbps or less with compression, a compressed video stream needs over a megabit per second to satisfy users’ TV experience. This is the reason for a broadband network connection. 譯文:IP數字包通過一個IP核心網。不同于只需64kbps或更小的壓縮的語音流，壓縮視頻流需要超過一個兆比特每秒來滿足用戶的電視體驗。這就是寬帶網絡的鏈接點。,Unit 9,原文：To ensure smooth delivery of the TV service, a service provider might need to provide dedicated connections and resources to ensure no interruption in the user experience. Therefore, a guaranteed path from the content source to the final distribution might have to be under watch by a network service provider 譯文:為了確保用戶電視節(jié)目的連續(xù)而流暢，服務提供商應提供連接和資源來確保用戶在視頻體驗時不會間斷。因此，從菜單資源到最終的分配之間的必定的路徑必須在網絡服務提供者的監(jiān)控之下。,Unit 9,原文：-Complex Operation Support Systems (OSS) are set up to fulfill service ordering ,service assurance, and billing functions. 譯文:為了實現(xiàn)業(yè)務的排序、業(yè)務的準確性以及工單的（整理）作用建立了綜合的運營支撐系統(tǒng),Unit 9,原文：There are a number of requirements for IPTV to be successful _Quality of service or QoS Some specific QoS mechanisms are required in a bandwidth-constrained access. A bandwidth allocation supported by a session-based admission control function is a reasonable assumption. A flow has to be set up along the whole transmission path. The quality requirements can be adjusted from time to time. Note that such a dynamic QoS scheme might require changes in the QoS policy to be propagated throughout the network infrastructure. 譯文:IPTV要成功必須具備以下的幾個必要條件： 服務質量 一些特殊服務質量的器件限制了帶寬的接入，按照會話來控制帶寬的分配是一個合理的假設。流量是按照整個的傳輸路徑來計算的。并且質量的要求要適應時代的發(fā)展。值得注意的是這種動態(tài)的服務質量標準要隨著那些在網絡基礎設施所宣傳的服務質量政策的改變而改變。,Unit 9,原文：_Multicast Use of multicast is a convenience for the operator to minimize network resources and not an essential component of the service definition. Protocol Independent Multicast (PIM) can help decouple the underlying routing protocol from broadcast services, using dense mode or sparse mode through the planning of IPTV coverage and usage in the network infrastructure. The IPTV service needs to be available whether the content is unicast (as in video on demand) or multicast (as in TV broadcast). 譯文:組播 組播的應用使得運營商很方便的優(yōu)化了網絡資源，并且這不是服務定義的主要部分。獨立多點協(xié)議可以通過廣播服務有效的減少下屬路由協(xié)議的損耗，它在網絡電視的覆蓋計劃中以密集模式或者稀疏的模式應用并使用在網絡基礎設施中。無論信息是單播的（像視頻的點播）或者組播的(像廣播電視)。,Unit 9,原文：_Authentication context This is similar to the presence service in VoIP convergence. The Internet TV stream can be one element within a communication context. Consider two teenagers watching the same movie (in their respective houses) and instant messaging each other at significant moments during the show. An alternative example is the TV stream as a picture-in-picture option within a multimedia conferencing service. 譯文:鑒定/授權/身份 網絡電視服務必須授于權一個特定的設備，更多復雜的個性化的授權模式需要一些特殊的服務。例如，家長控制。,Unit 9,原文：Nomadicity For an Internet TV service, nomadicity normally is interrupted as the user being able to access the same service profile from a different location. Performance-to-cost ratio changes are likely to result in handheld devices or portable terminals capable of participating in Internet TV sessions. 譯文:通信范圍 這就和現(xiàn)存的使用了互聯(lián)網協(xié)議的網絡上進行語音傳輸相類似，網絡電視的數據流是通信范圍中的一個元素。考慮到兩個青年同時觀看相同的電影（在各自的房間）并且在觀看期間每個重要的時刻瞬時的信息都是相同的。具體的例子就是電視流就像多媒體會議業(yè)務中的一幅一幅的畫面一樣。,Unit 9,原文：_Emergency IPTV needs to continue existing television services to provide content overlays notifying of emergency conditions (for example, a thunderstorm warming). 譯文:游牧 在網絡電視業(yè)務中，游牧通常被解釋為用戶可以從不同的側面來定義一些服務的一面。性能與開銷的比值的變化很可能直接影響在手持設備或移動終端在網絡電視會議中的是否可用。,Unit 9,原文：_Content and service discovery Assisted by a centralized or distributed directory, the user is able to search and locate the video content from the terminals. The search can be text-,picture-.or video-based. The content and the service available based on the content is reported back to the user as the result of search. As the cable and phone service providers are moving into the content service, they face integration of various servers, some of which might contain the same content with varying format, abbreviation, or technology. 菜單與服務的產生 通過集中的或分散的目錄的輔助，用戶可以從終端查找和定位視頻菜單，這種搜索可以是基于文本、基于圖片或是基于者視頻的。我們稱這種業(yè)務和基于菜單的可用服務是用戶搜索的結果。由于電報或者手機的服務總是在菜單服務中變化，他們面對著各種各樣的菜單的提供者的整合，例如，對一個電視節(jié)目的菜單的重新搜索要經過網際層對各種的服務層的復用，這也包括很多具有不用格式、縮寫、或者技術的同一個菜單。,Unit 9,原文：_Digital rights management IP network security and application security support DRM technology that allows certification of the legitimacv of the original source of the video content, authentication and authorization of the user to view the content, and clear accounting among content creators, producers, traders, and users. 譯文:數字化的管理 IP網絡安全和應用安全支持ＤＲＭ技術，它證明了最初的視頻目錄資源的合理性并且對與用戶觀看菜單予以授權，明確的闡釋了在菜單的創(chuàng)作者、制造者、交易商和用戶(的關系)。,Unit 9,原文：_Session management Standard session management control commands must be built on top of the SIP or RTCP or other protocols in order for users to initiate and control delivery. Examples include play, rewind, forward, pause, stop, fast rewind, and faster forward. 譯文:會話管理 會話管理控制協(xié)議是在SIP 或RTCP或者其他的協(xié)議的基礎上為了用戶的使用以及菜單的控制交付而創(chuàng)造的，其中包括向前、倒換、倒回、暫停、停止、快速倒回和快速倒換。,Unit 9,原文：To meet the IPTV service requirements, a set of enabling capabilities have to provide middleware in the SP space . those enabling technologies are directly supported by a number of IETF protocols including Real-Time Protocol Real-Time Control Protocol ,and Stream Control Transmission Protocol. 譯文:為了滿足IPTV的業(yè)務需求，在SP的容量中的中間設備中留有一系列可用的容量，這些可用的技術支持包括實時傳輸協(xié)議、實時傳輸控制協(xié)議、流量傳輸控制協(xié)議的一系列IETF協(xié)議。,Unit 9,原文： IPTV offerings stem from competing needs between cable and phone service providers . Of course, new IPTV technologies and applications ,in turn ,benefit content providers, as well as new user experence. 譯文: IPTV的產生起源于電報和電話服務提供者的競爭，當然，作為回報，新的IPTV的技術和應用使菜單的提供者和新用戶體驗得到了益處,Unit 9,原文：IP services provide a number of benefits: To the users, IPTV technology enables them to select the content they want and pick the time they want to wach. They can use the devices they want and available to them . thin clients will be embeded in various devices. 譯文:IP業(yè)務提供了下面的好處： 對于用戶，IPTV技術可以使他們去選擇他們想要的節(jié)目以及選擇自己的時間去觀看。他們可以用自己合適的設備來實現(xiàn)這些。所以便攜式電腦就鑲嵌在各種各樣的設備中。,Unit 9,原文：The content providers add new distribution opportunities. They can provide targeted custom TV services and commerce with the collection of usage data. 譯文:菜單提供者增加了很多分配的機遇，他們通過收集用戶的數據定向的和電視業(yè)務的用戶來進行進行貿易,Unit 9,原文：The application service providers can simplify intergration of IP content and services (such as IP packetized weather, games, photos, and music on TV). For example ,TV can be integrated with broadband home devices though a set-top box (STB). The IP STB is the TV’s gateway to digital music, home videos. and photos. 譯文:這種服務應用的提供者可以很容易的整合IP菜單和業(yè)務（像在電視上的天氣預報、游戲、圖片和音樂的IP 包得封裝）。例如，電視可以通過網絡機頂盒將寬頻的家庭設備整合起來，網絡機頂盒是電視接收數字音樂、家庭視頻和圖像的網關。,Unit 9,原文：The cable and phone service providers find a level play field to compete in triple-play for data, voice, and video. 電報和電話服務提供商發(fā)現(xiàn)了一個傳輸水平領域來競爭數據、語音和視頻的三倍速率的傳輸。,Unit 9,原文：Traditionally, cable and wireless offered separate (no overlap) services with different network infrastructures. As they move toward the same service space and with a common IP domain we (the authors) predic integration and mergers across cable and phone industry ,as a consequence of the same triple-play ground place. 譯文： 傳統(tǒng)的電纜和無線電波利用網絡底層結構提供了獨立（不重疊的）的服務。由與我們用相同的IP地址和同樣地設備通信時，（作者）預言可以整合和合并電報和電話行業(yè)，結果就是在地面空間的三倍的速率的傳輸。,作業(yè)： 1、本課的擴展閱讀1-2段翻譯 2、預習下一單元課文,Unit 9,Thank You !,