下列关于上颌骨支架结构的描述，不正确的是

four choices and write down in the answer sheet.

The key to SNMP(66)is its simplicity. It has a small command set that does a good job of collecting information from(67)any network device. In a SNMP environment,(68)of the work is handled by the network management system. Devices that are being managed are not(69)with processing(70)that might affect their performance.

A．popularity

B．function

C．efficiency

D．power

four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private-key encryption methods are called(71)ciphers, information is encrypted with(72)both the sender and receiver hold privately. Public-key encryption methods are called(73)ciphers,(74)created for each user, encryption key and decryption key are(75)

A．synchronous

B．Asynchronous

C．symmetric

D．asymmetric

four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private-key encryption methods are called(71)ciphers, information is encrypted with(72)both the sender and receiver hold privately. Public-key encryption methods are called(73)ciphers,(74)created for each user, encryption key and deception key are(75)

A．synchronous

B．Asynchronous

C．symmetric

D．asymmetric

four choices and write down in the answer sheet.

The key to SNMP(71)is its simplicity. It has a small command set that does a good job of collecting information from(72)any network device. In a SNMP environment,(73)of the work is handled by the network management system. Devices that are being managed are not(74)with processing(75)that might affect their performance.

A．popularity

B．function

C．efficiency

D．power

four choices and write down in the answer sheet.The key to SNMP(76)is its simplicity. It has a small command set that does a good job of collecting information from(77)any network device. In a SNMP environment,(78)of the work is handled by the network management system. Devices that are being managed are not(79)with processing(80)that might affect their performance.

A．popularity

B．function

C．efficiency

D．power

four choices and write down in the answer sheet. Heterogeneous network environments consist of computer systems from(66)vendors that run(67)operating systems and communication protocols. An organization that(68)its computer resources is usually(69)the task of integrating its heterogeneous systems. Typically, each deparlment or division has defined its own network needs(70)OS, LAN topology, communication protocols,applications, and other components.

A．same

B．similar

C．different

D．difference

four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private - key encryption methods are called(66)ciphers, information is encrypted with(67)both the sender and receiver hold privately. Public - key encryption methods are called(68)ciphers,(69)created for each user, encryption key and decryption key ale(70).

A．synchronous

B．Asynchronous

C．symmetric

D．asymmetric

four choices and write down in the answer sheet. Heterogeneous network environments consist of computer systems from(66)vendors that run(67)operating systems and communication protocols. An organization that(68)its computer resources is usually(69)the task of integrating its heterogeneous systems. Typically, each deparlment or division has defined its own network needs(70)OS, LAN topology, communication protocols, applications, and other components.

A．same

B．similar

C．different

D．difference

four choices and write down in the answer sheet. Heterogeneous network environments consist of computer systems from(66)vendors that run(67)operating systems and communication protocols. An organization that(68)its computer resources is usually(69)the task of integrating its heterogeneous systems. Typically, each deparlment or division has defined its own network needs(70)OS, LAN topology, communication protocols, applications, and other components.

A．same

B．similar

C．different

D．difference

four choices and write down in the answer sheet.Open Shortest Path First(OSPF) is a(36)routing algorithm that(37)work clone on the OSI IS-IS intradomain routing protocol. This routing, as compared to distance-vector routing, requires(38)processing power. The(39)algorithm is used to calculate routes. OSPF routing table updates only take place when necessary,(40)at regular intervals.

A．distance-vector

B．link-state

C．flow-based

D．selective flooding