Which of the following are common issues that should be considered when establishing ortroubleshooting site-to-site VPNs？（Choose all that apply.）（）

A.Cisco proprietary
B.Standards-based protocol
C.Provides separate services for authentication， authorization， and accounting
D.Encrypts only the password
E.Uses UDP for a transport layer
F.Encrypts the entire packet

A.clear nat translations
B.clear ip nat translations*
C.clear ip nat statistics
D.clear ip nat transactions*
E.clear ip nat translations
F.clear ip nat translations all

A.EIGRP advertises the best routes to its neighbor
B.EIGRP uses "cost" to determine best path
C.EIGRP allows unequal cost load balancing
D.OSPF requires neighbor adjacencies before updates are sent
E.EIGRP advertises all routes to its neighbor
F.OSPF allows unequal cost load balancing