研究了在集成服务用于用户子网和区分服务结构用于主干网时,为保证服务质量而进行 服务映射的问题.基于已有的分类方法,建立了应用类与集成服务(integrated service,简称 IS)类、集成服务类和区分服务(differentiated service,简称DS)类、数据流和PHB(par ho p bahavior)的对应和映射关系.标识是服务映射中的关键,该文把它分为预标识和标识两个 过程,IS域确定的预标识码携带单个数据流的特性到DS域,DS域的边界路由器根据预标识码准 确地标识数据包和映射P
In this paper, the authors propose a method for mapping QoS (quality of service) guarantees between ISs (integrated services) and DSs (differentiated services) in the Internet environment. Based on the existing classification, this paper gi v es the mapping rules and relations between IS and DS, data flows and PHBs (per h op behaviors) according to different media streams. As the crux of mapping, mark ing is divided into two phases: pre-mark and mark. The pre-code marked in IS c onveys characteristics of individual flow into DS. According to this pre-code, boundary routers in DS remark packets and map it to relevant PHB. The authors al so propose a marking algorithm which is based on the TCA (traffic condition agre ement), taking account of the requirements of traffic control and fair link shar ing among different application traffics.
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