There is no disadvantage.
It will add 16 bytes per packet of overhead(8 bytes UDP header, and 8 bytes of NON-IKE Marker).
It will add 36 bytes per packet of overhead (20 bytes of IP header, 8 bytes of UDP header, 8 bytes of NON-IKE Marker).
It will require that both crypto peers support this feature in the IOS version. Both crypto peers must also have this feature enabled.
第1题：
A. VPN establishment
B. packet-based forwarding
C. stateful packet processing
D. network address translation
第2题：
A. The summarized address for all internal subnetted addresses.
B. A private IP address assigned to a host on the inside network.
C. A registered address that represents an inside host to an outside network.
D. A unique IP address used on an internal network
E. Non of the above
第3题：
What refers to the protocols used to determine who goes next on a multi-access channel?(29)
A．MAC(medium access control)
B．ARP(address resolution protocol)
C．NAT(network address translation)
D．CIDR(classless interdomain routing)
第4题：
What are disadvantages of Network Address Translation Transparency?（）
第5题：
What are the advantages and disadvantages of grammar-translation method?
The main advantages of this method are: first, comparison between two languages helps students to have a better understanding of the meaning of abstract words and complicated sentences. Second, systematic study of grammatical rules plays an important role in fostering students' ability of reading comprehension and producing grammatically correct sentences. Understanding and manipulating the morphology and syntax will develop students' ability of analyzing and solving problems. Third, the focus on understanding literary texts provides the situation in which reading and writing abilities are well trained. Fourth, it makes few demands on teachers although it often creates frustration for students. It is relatively easy to apply.
Disadvantages in this method are: First, overemphasis on translation can never emancipate the learners from dependence on the first language. Second, knowing a large number of grammatical rules cannot ensure that students can use them appropriately in real communicative situation. Third, it puts too much emphasis on reading and writing and neglects listening and speaking. Fourth, the texts are mostly taken from literary works. The language learned often doesn't meet the practical needs of the learners. Fifth, memorizing grammar rules and bilingual word lists does not motivate students to actively communicate in the target language.
略
第6题：
A router that performs Network Address Translation (NAT) is installed between your computer and the Internet.The router fails. You connect the computer directly to the Internet.You need to ensure that the computer is connected to the Internet in the most secure manner possible.What should you do?（）
A.A
B.B
C.C
D.D
第7题：
A.201.100.5.0
B.201.100.5.32
C.201.100.5.64
D.201.100.5.65
E.201.100.5.31
F.201.100.5.1
第8题：
A network administrator has configured source NAT, translating to an address that is on a locally connected subnet.The administrator sees the translation working, but traffic does not appear to come back.What is causing the problem?（）
A. The host needs to open the telnet port.
B. The host needs a route for the translated address.
C. The administrator must use a proxy-arp policy for the translated address.
D. The administrator must use a security policy, which will allow communication between the zones.
第9题：
What parameters must you specify when you enable EIGRP routing?（）
第10题：
What is the purpose of a network mask?（）