【摘要】 为了解决NAT所带来的穿越问题,业界提出多种方案如ALG,STUN,TURN等,但它们在网络拓扑和应用可扩展性上都具有一定的局限性。在此参考STUN协议和TURN协议,设计并实现了一个基于ICE方式的综合性解决方案,拥有ICE模块的客户端在发起和接收呼叫前会收集所有可能用于媒体流传输的地址,然后从中选择最优传输路径进行媒体流传输,从而克服了传统方案的不足,具有很强的适应能力,能工作在任何拓扑环境中。更多还原

【Abstract】 Numerous solutions including ALG,classic STUN,TURN etc,have been defined for allowing higher level singaling protocol such as the Session Initiation Protocol to work through NAT,but these techniques are limited to work only in certain network toplogies.A new completely solution to the NAT traversal-Interactive Connectivity Establishmentis(ICE) is introduced.ICE is a not a new method but making use of existing protocol such as STUN and TURN.Before initializing or answering a session,ICE-enabled UAs can collect all candidates that may be used for media transfer,and choose one optimal candidate-pair for mediastream.ICE can work in every topologies,overcome the shortcomings of traditional sulotions.更多还原