組播技術(shù)基礎(chǔ)(編輯修改稿)
2024-09-01 11:07 本頁面
【文章內(nèi)容簡介】 n Steve Deering39。s doctoral thesis, Multicast Routing in a Datagram Network, published in December 1991.Dr. Deering39。s thesis also described a Host Membership Protocol, which became the basis for today39。s Inter Group Membership Protocol (IGMP) that IP multicast hosts use to signal to the router on the work that they desire to join a multicast group. In addition, Dr. Deering39。s thesis described a distance vectorbased IP multicast routing protocol that was the basis for the Distance Vector Multicast Routing Protocol (DVMRP), also developed by Dr. Deering a few years later. These two protocols provided the first successful extensions to the IP packet work model to allow multicasting to be extended to Layer 3 of the OSI model. Since that time, advances in IP multicasting technology have continued and additional protocols such as Protocol Independent Multicasting (PIM) and multiprotocol extensions to the Border Gateway Protocol (BGP) have been developed. These protocols permit IP multicasting to scale beyond the initial limited implementations to large, enterprisewide multicast works and eventually on to a native, pletely multicastenabled Inter.n 組播基礎(chǔ)知識組播通信模型n 單播通信模型q 點(diǎn)到點(diǎn)q 以目的為中心，靠目的 IP地址來決定轉(zhuǎn)發(fā)。單播轉(zhuǎn)發(fā)項(xiàng)形式為 (目的網(wǎng)段 ,出接口 ,下一跳 )：n (,Ether0,)q 隨著通信參與者的增加，網(wǎng)絡(luò)帶寬消耗隨之增加123123n 組播通信模型q 點(diǎn)到多點(diǎn)123123n 組播通信模型q 組播四要素：– 源發(fā)現(xiàn)– 接收者發(fā)現(xiàn)– 拓?fù)浒l(fā)現(xiàn)（組播路由器之間的拓?fù)?、網(wǎng)絡(luò)單播路由信息）– 分發(fā)樹生成PIMSM/DM/SSM DVMRP MSDPIGMPDVMRP 單播： OSPF RIP BGP StaticRoutePIMSM/DM/SSM DVMRPn 組播通信模型q 以源和目的為轉(zhuǎn)發(fā)依據(jù)－ (S, G)，樹狀的轉(zhuǎn)發(fā)，網(wǎng)絡(luò)負(fù)載不隨用戶規(guī)模增加而增加（樹從根部開始一直到葉子都是一樣粗）。組播源接收者接收者 接收者 接收者n 組播通信模型q 轉(zhuǎn)發(fā)樹的構(gòu)建， RPF（ Reverse Path Forwarding）q 組播轉(zhuǎn)發(fā)項(xiàng)形式為：(組播源地址 , 組播組地址 , 入接口 , 出接口列表 )(,eth0,{eth1,eth2… })Eth0Eth1目的 下一跳 接口...S ... Eth0...單播路由表Eth0Eth1接收者 R1接收者 R2組播源 S216。 組播基本概念216。 組播基礎(chǔ)協(xié)議216。 組播應(yīng)用n 組播基礎(chǔ)協(xié)議q 用戶發(fā)現(xiàn)協(xié)議– IGMP（ V V V3），用于了解接口所連接的網(wǎng)絡(luò) 是否 有主機(jī)加入某組播組q 組播路由協(xié)議q 組播源發(fā)現(xiàn)協(xié)議q 組播拓?fù)浞蛛x協(xié)議q 二層組播協(xié)議q 組播協(xié)議典型組網(wǎng)組播網(wǎng)絡(luò)查詢報(bào)告IGMPn IGMP 組成員加入、維護(hù)查詢器X IGMP 報(bào)告 IGMP 查詢路由器發(fā)送查詢IP地址最小路由器選舉成為查詢器 主機(jī) 主機(jī) 路由器周期性維護(hù)組成員關(guān)系主機(jī) 路由器周期性維護(hù)組成員關(guān)系Xn IGMP 組成員離開查詢器 IGMP 報(bào)告 IGMP 離開 IGMP 查詢主機(jī) 主機(jī) 主機(jī) n IGMPv1 v2 v3的差別q IGMP v1– 沒有主動離開消息q IGMP v1 v2– 指定加入的組q IGMP v3– 指定加入的 源 組，配合 PIMSSM使用n 組播基礎(chǔ)協(xié)議q 用戶發(fā)現(xiàn)協(xié)議q 組播路由協(xié)議– 掌握網(wǎng)絡(luò)拓?fù)洌l(fā)現(xiàn)組播源，生成轉(zhuǎn)發(fā)樹q PIMSM/DM/SSMq DVMRP...q 組播源發(fā)現(xiàn)協(xié)議q 組播拓?fù)浞蛛x協(xié)議q 二層組播協(xié)議q 組播協(xié)議典型組網(wǎng)組播網(wǎng)絡(luò)組播路由協(xié)議組播源n PIM 協(xié)議密集模式Protocol Inde
公司管理相關(guān)推薦
鄂ICP備17016276號-1