TK的一道新题，有高手解释一下吗？？

蓝色飞鱼

<FONT size=6>How does route poisoning work with holddown timers to prevent routing loops?<BR>A.Information learned from one source is not distributed back to that source.<BR>B.Routing updates from the poisoned source are ignored until a holddown timer expires.<BR>C.Failed routers are advertised with infinite metrics.<BR>D.New routing updates are ignored until the network has converged.<BR>E.A route is marked as unavailable when its time-to-live is exceeded.</FONT>

sky-worm

<P>请问，还有一种方法，是叫做 最大路由</P><P>它好象是将metric设置成16哦</P><P>跟路由中毒,有什么区别???</P>

王晓强

<P>这题是考查路由中毒的概念。</P><P>答案是Ｃ，路由中毒就是将路由通告给别人时加上一个无限大的ｍｅｔｒｉｃ值，使之认为不可达。</P><P>Ａ是水平分割的一种描述。<BR></P>