A.物理層B.網(wǎng)絡(luò)層C.鏈路層D.應(yīng)用層
A.224.0.0.1 B.224.0.0.2 C.224.0.0.3 D.224.0.0.9
A.PIM B.IGRP C.IGMP D.DVMRP