One of the most widely used routing protocols in IP networks is the Routing Information Protocol（RIP）. RIP is the canonical example of a routing protocol built on the（ ）algorithm.Routing protocols in internetworks differ slightly from the idealized graph model.In an internetwork，the goal of the routers to forward packets to various（ ）.
Routers running RIP send their advertisement about cost every （ ）seconds.A router also sends an update message whenever an update from another router causes it to change its routing table.
It is possible to use a range of different metrics or costs for the links in a routing protocol.RIP takes the simplest approach，with all link costs being equal （ ）. Thus it always tries to find the minimum hop route.Valid distances are 1 through（ ）.This also limits RIP to running on fairly small networks.
问题1选项
答案： A、D、B、A、C。
IP网络中广泛使用的路由协议之一是路由信息协议（RIP）。RIP是基于 路由算法的路由协议。网络中的路由协议与理想的图算法存在少量的差异。在互联网中，路由器的目的是将数据包转发给不同的 。
运行RIP协议的路由器每 秒广播一次路由信息，另外，每当路由器收到其他路由器的更新消息而导致其路由表变化时，就会发送更新消息。
路由协议使用不同的度量或成本来建立连接是可能的。RIP采用了最简单的方法，所有链路的成本都等于 。这样，它总是试图寻找跳数最少的路径。有效的距离范围是从1到 。这也限制了RIP只能在相当小规模的网络上运行。
