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In(66)the strength of the carrier signal is varied to represent binary 1 or 0.(67)is a system that can map a name to an address and conversely an address to al name.(68)is a three-way handshaking authentication protocol that it's packets are encapsulated in the point-to-point protocol.(69)is an approach that enables an ATM switch to behave like a LAN switch.(70)is an guided media which is made of glass or plastic and transmits signals in the form. of light.

A．ASK

B．PSK

C．FSK

D．FDM

In(66)the strength of the carrier signal is varied to represent binary 1 or 0.(67)is a system that can map a name to an address and conversely an address to an name.(68)is a three -way handshaking authentication protocol that it's packets are encapsulated in the point - to -point protocol.(69)is an approach that enables an ATM Switch to behave like a LAN switch.(70)is an guided media which is made of glass or plastic and transmits signals in the form. of light.

A．FDM

B．DSK

C．FCK

D．ASK

● (71) In the strength of the carrier signal is varied to represent binary 1 or 0．

(72) is a system that can map a name to an address and conversely an address to an name．

(73) is a three-way handshaking authentication protocol that it's packets are encapsulated in the point-to-point protocol

(74) is an approach that enables an ATM Switch to behave like a LAN switch．

(75) is an guided media which is made of glass or plastic and transmits signals in the form. of light．

(71) A．ASK

B．PSK

C．FSK

D．FDM

(72) A．NAT

B．NCP

C．DDN

D．DNS

(73) A．PPP

B．PAP

C．CHAP

D．LCP

(74) A．VLAN

B．LANE

C．VPN

D．IPOA

(75) A．Coaxial cable

B．Optical fiber

C．Unshielded Twisted-pair Cable

D．Shielded Twisted-pair Cable

In(66)the strength of the carder signal is varied to represent binary 1 or 0.(67)is a system that can map a name to an address and conversely an address to an name.(68)is a three-way handshaking authentication protocol that it's packets are encapsulated in the point-to-point protocol.(69)is an approach that enables an ATM Switch to behave like a LAN switch.(70)is an guided media which is made of glass or plastic and transmits signals in the form. of light.

A．ASK

B．PSK

C．FSK

D．FDM

A．A.Relative signal strength

B．B.Absolute signal strength

C．C.Minimum signal strength

D．D.Sufficient signal strength

E．E.Quality

A．A.Receive Quality, Receive Signal Strength, Distance, Power Budget, Interference

B．B.Receive Quality, Interference, Receive Signal Strength, Distance, Power Budget

C．C.Receive Signal Strength, Receive Quality, Interference, Distance, Power Budget

D．D.Receive Signal Strength, Receive Quality, Distance, Power Budget, Interference