Which three items are Cisco best-practice recommendations for securing a network？（）

单项选择题Examinethefollowingitems，whichoneoffersavarietyofsecuritysolutions，includingfirewall，IPS，VPN，antispyware，antivirus，andantiphishingfeatures？（）

A.Cisco IOS router
B.Cisco PIX 500 series security appliance
C.Cisco 4200 series IPS appliance
D.Cisco ASA 5500 series security appliance

单项选择题BeforeaDiffie-Hellmanexchangemaybegin，thetwopartiesinvolvedmustagreeonwhat？（）

A.Two secret keys
B.Two nonsecret keys
C.Two secret numbers
D.Two nonsecret numbers

单项选择题Based on the username global configuration mode command displayed in the exhibit. What does the optionsecret 5 indicate about the enable secret password？（）

A.It is hashed using MD5
B.It is encrypted using a proprietary Cisco encryption algorithm
C.It is hashed using SHA
D.It is encrypted using DH group 5

单项选择题Whichkindoftablewillbeusedbymostfirewallstodaytokeeptrackoftheconnectionsthroughthefirewall？（）

A.reflexive ACL
B.dynamic ACL
C.queuing
D.netflow
E.state

单项选择题TheenablesecretpasswordappearsasanMD5hashinarouter’sconfigurationfile，whereastheenablepasswordisnothashed（orencrypted，ifthepassword-encryptionserviceisnotenabled）.WhatisthereasonthatCiscostillsupporttheuseofbothenablesecretandenablepasswordsinarouter’sconfiguration？（）

A.The enable password is present for backward compatibility.
B.Because the enable secret password is a hash， it cannot be decrypted. Therefore， the enable password is used to match the password that was entered， and the enable secret is used to verify that the enablepassword has not been modified since the hash was generated.
C.The enable password is considered to be a router’s public key， whereas the enable secret password is considered to be a router’s private key.
D.The enable password is used for IKE Phase I， whereas the enable secret password is used for IKE Phase II.