61.Network frewalls are security devices used to stop or mitigate (71) access to private networks connected to the Internet, especially intranets. The only trafle alowed on thev network is defined via firewall (72)-any other taff attempting to access the network is blocke
D. Network firewalls sit at the (73) line of a network, acting as a communications
liaison between intemal and gxtemal devics, When properly configured, a firewall alws users to access any of the resources they need while simultaneously keeping out unwanted accesses. In addition to limiting access to a protected computer and network, a firewall can (74) all traffit coming into or leaving a network, and manage remote access to a private network through secure authentication grtificates and logins. (75) firewalls examine every packet that passes through the network and then accep or deny it as defined by rules set by the user.
(71) A unauthorized
B.authorized
C.normal
D. frequent
(72) A ports
B.policies
C.commandse
D. statuse
(73) A.front
B.back
C.second
D. last
(74) A. reply
B.block
C.log
D.encrypt
(75) A. Application-layer
B.Packet fitering
C.Circui-level
D.Proxy server
