【正文】 l munication path, or virtual circuit, between processes exchanging a fullduplex stream of bytes. Each process is assumed to reside in an Inter host that is identified by an IP address. Each process has a number of logical, fullduplex ports through which it can set up and use as fullduplex TCP connections. 用戶數(shù)據(jù)報文協(xié)議 UDP ? User Datagram Protocol(DUP) ? UDP是 Inter網(wǎng)絡(luò)協(xié)議 IP的擴展 ， 它支持?jǐn)?shù)據(jù)報文的多路復(fù)合 。 它只提供多路復(fù)合及檢查和控制 。 使用UDP的高層協(xié)議必須自己提供重傳 、 打包 、 重組 、 漢控制和擁擠避免等 。 ? UDP is a simple extension to the Inter work protocol IP that supports multiplexing of datagrams exchanged between pairs of Inter hosts. It offers only multiplexing and checksumming, nothing else. Higherlevel protocols using UDP must provide their own retransmission, packetization ,reassembly, folw control, congestion avoidance, etc. ? 2． 實時傳輸協(xié)議 （ RTP） Realtime Transport Protocol(RTP) ? RTP是一種端對端協(xié)議 ， 提供網(wǎng)絡(luò)傳輸功能 ，適合于應(yīng)用系統(tǒng)傳輸實時數(shù)據(jù) ， 例如音頻 、 視頻或多點發(fā)送或單點發(fā)送網(wǎng)絡(luò)服務(wù)上的并發(fā)數(shù)據(jù) 。它由 A u d i o / V i d e o T r a n s p o r t W o r k i n g Group[SCFJ94]定義 。 ? RTP is an endtoend protocol providing work transport functions suitable for applications transmitting realtime data, such as audio, video or simulation data over multicast or unicast work services. It is specified and still augmented by the Audio\Video Transport Working Group[SCFJ94]. ? RTP有一相關(guān)協(xié)議 RTCP（ RTP控制協(xié)議 ） ，負(fù)責(zé)傳送有關(guān)會議參加者的信息 。 RTP提供諸如媒體編碼確定 、 同步 、 幀 、 錯誤檢測 、加密 、 定時和源標(biāo)識等功能 。 RTCP負(fù)責(zé)監(jiān)控某一正在進行的佳話的 QoS參數(shù)以及傳送參加者的信息 。 RTCP的第一部分 （ 監(jiān)控作用 ） 由稱為 QoS監(jiān)控器的應(yīng)用實現(xiàn) ， 它接收RTCP消息 。 監(jiān)控器估算當(dāng)前 QoS參數(shù) 、 錯誤診斷以及一段時間內(nèi)的統(tǒng)計信息 。 RTCP的第二部分用于基于 “ 松散控制 ” 的會話 。RTP和 RTCP住處通過不同的端傳輸 。 ? RTP has a panion protocol RTCP (RTPControl Protocol) to convey information about the participants of a conference. RTP provides functions, such as determination of media encoding, synchronization, framing, error detection, encryption, timing and source identification. RTCP is used for the monitoring of QoS and for conveying information about the participants in an ongoing session. The first aspect of RTCP, the monitoring ,is done by an application called a QoS monitor, which receives the RTCP messages. This monitor estimates the current QoS for monitoring, fault diagnosis and longterm statistics. The second aspect of RTCP is used for “ loosely controlled” sessions. RTP and RTCP information is transmitted through separate ports. ? 3． Xpress傳輸協(xié)議 （ XTP） ? Xpress Transport Protocol(XTP) ? XTP是一高效的協(xié)議 [SDW92]。 XTP專題討論會仍舊討論如何再提高它的性能 ， 為各種應(yīng)用提供更好的平臺 。XTP集成傳輸和網(wǎng)絡(luò)協(xié)議功能 ， 為它所操作的環(huán)境提供更多的控制 [Che94]。 ? XTP was designed to be an efficient protocol, taking into account the low error ratios and higher speeds of current works [SDW92]. It is still in the process of augmentation by the XTP Forum to provide a better platform for the ining variety of applications. XTP integrates transport and work protocol functionalities t have more control over the environment in which it operates[Che92]. ? 4. 其他傳輸協(xié)議 Other Transport Protocols ? ⑴ Te 傳輸協(xié)議 Te Transport Protocols ? 用于支持多媒體傳輸?shù)?Te 協(xié)議集由加利福尼亞大學(xué)伯克萊分校的 Te組開發(fā)成功 。 該協(xié)議中的傳輸協(xié)議是實時消息傳輸協(xié)議（ RMTP） 和連續(xù)媒體傳輸協(xié)議 （ CMTP） 。 它們在實時 Inter協(xié)議 （ RTIP） 之上運行 。 ? The Te protocol suite for support of multimedia transmission was developed by the Te Group at the University of California at Berkeley, The transport protocols in this protocol stack are the Realtime Message Transport Protocol (RMTP) and Continuous Media Transport Protocol(CMTP). They run above the RealTime Inter Protocol (RTIP). ? ⑵ Heidelberg傳輸系統(tǒng) （ HeiTS） Heidelberg Transport System(HeiTS) ? Heidelberg 傳輸系統(tǒng)（ HeiTS）用于多媒體通信的傳輸系統(tǒng)。它由位于 Heidelberg的 IBM Continuous media Realm (HeiCoRe)，那是工作站上處理多媒體數(shù)據(jù)的實時環(huán)境。 ? The Heidelberg Transport System(HeiTS) is a transport system for multimedia munication. It was developed at the IBM European Networking Center(ENC), Heidelberg. HeiTS provides the raw transport of multimedia over works. It uses the Heidelberg Continuous media Realm(HeiCoRe), which is a realtime environment for handling multimedia data within workstations. ? ⑶ METS：多媒體增強傳輸服務(wù) METS: A Multimedia Enhanced Transport Service ? METS是 Lancaster大學(xué)開發(fā)的多媒體傳輸服務(wù) [CCH93a]，在 ATM網(wǎng)的頂層運行。 ? METS is the multimedia transport service developed at the University of Lancaster[CCH93a]. It runs on top of ATM works. 謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAIT