When routing is based on some header characteristic such as explicit routing information that is carried in a routing header , the service requestor and proxy service implementations are coupled and must be kept up to date as the format of the routing header evolves 當(dāng)路由是基于頭標(biāo)記特征時(例如在路由頭中帶的直接路由信息) ,服務(wù)請求者和代理服務(wù)實現(xiàn)被聯(lián)系在了一起,而且它們必須隨著路由頭格式的發(fā)展而保持最新。