A.P2P B.广播 C.NBMA D.P2MP
A.Broadcast B.NBMA C.Point-to-point D.Point-to-multipoint
A.IS-IS B.IGRP C.OSPF D.EIGRP
A.Local-preferance B.MED C.Origin D.Community
A.BGP B.IS-IS C.RIP D.OSPF
A.TCP B.UDP C.IP D.PPP
