A. Generic Router Encapulation
B. Generic Routing Encapulation
C. General Routing Encapulation
D. General Router Encapulation

A.創(chuàng)建tunnel虛擬接口，使需要加封裝的報(bào)文通過隧道接口進(jìn)行轉(zhuǎn)發(fā)
B.隧道源端對報(bào)文加封裝
C.加封裝處理結(jié)束后由GRE負(fù)責(zé)報(bào)文轉(zhuǎn)發(fā)
D.隧道對端的解封裝過程