GRE是GenericRoutingEncapsulation通用路由封装的简称。()
第1题:
In IPv6 network, an IPv6 overlay tunnel is required to communicate with isolated IPv6 networks across the existing IPv4 infrastructurE. There are currently fiv e IPv6 overlay tunnel types.Which three IPv6 overlay tunnel statements are true?()
A. Overlay tunnels can only be configured between border routers capable of supporting IPv4 and IPv6.
B. An manual overlay tunnel supports point - to - multipo int tunnels capable of carrying IPv6 and Connectionless Network Service (CLNS) packets.
C. Overlay tunneling encapsulates IPv6 packets in IPv4 packets for delivery across an IPv4 infrastructure.
D. Overlay tunnels can be configured between border route rs or between a border router and a host capable of supporting IPv4 and IPv6.
E. Cisco IOS supports manual, generic routing encapsulation (GRE), IPv4 - compatible, 6to4, and Intra - Site Automatic Tunnel Addressing Protocol (ISATAP) overlay tunneling mechan isms.
F. Cisco IOS supports manual, generic routing encapsulation (GRE), IPv6 - compatible, 4to6, and Multiprotocol Label Switching (MPLS) overlay tunneling mechanisms.
第2题:
A.GRE实际上是第三层的一种隧道运载协议
B.有效报文被GRE封装,称之为GRE报文
C.GRE报文被封装在外层的承载网络层报文(如IP协议报文)中
D.承载网络层负责对GRE报文的传输
第3题:
GRE是由思科开发的隧道协议,可以在IP隧道内封装()。
第4题:
A.创建tunnel虚拟接口,使需要加封装的报文通过隧道接口进行转发
B.隧道源端对报文加封装
C.加封装处理结束后由GRE负责报文转发
D.隧道对端的解封装过程
第5题:
A.GRE用于对某些网络层协议(如:IP、IPX、AppleTalk等)的数据报进行封装,使这些被封装的数据报能够在IP网中传输
B.GRE是二层隧道协议
C.GRE在网络层之间采用了Tunnel(隧道)的技术
D.GRE是实现VPN所必需的协议