The Border Gateway Protocol (BGP) is an interautonomous system （） protocol. The primary function of a BGP speaking system is to exchange network （） information with other BGP system. This network reachability information includes information on the list of Autonomous System (ASs) that reachability information traverses. BGP-4 provides a new set of mechanisms for Supporting （） interdomain routing. These mechanisms include support for advertising an IP （） and eliminate the concept of network class within BGP. BGP-4 also introduces mechanisms that allow aggregation of routes, including （） of AS paths. These changes provide support for the proposed supernettting scheme.
BGP-4 also introduces mechanisms that allow aggregation of routes, including （） of AS paths.
A．reservation
B．relation
C．aggregation
D．connection
参考答案：C
解析：
[分析]： 边界网关协议BGP是自治系统间的路由协议。BGP发布系统的基本功能就是与其他BGP系统交换网络可到达性信息。这种网络可到达性信息包含了可到达性信息穿越的自治系统的列表。BGP-4提供了一系列新的机制来支持无类别的域间路由。这些机制包括支持发布IP前缀，从而在BGP中排除了网络类别的概念。BGP-4也引入了路由聚合机制，包括AS通路的聚合。这些改变提供了对提议的超网方案的支持。