问答题
What are the three main types of networks that must be considered when defining a security policy？
Trusted， untrusted， unknown.
问答题 WhatisthepurposeoftheRouteTagfieldintheRIPv2message？
问答题 Youaresubnetinginthenetwork，outofnetworkaddress，what’sfeaturecanaddonemoreaddress？
问答题 ExplainRouteAggregationinBGP.
