传输层的PDU叫（），网际层的PDU叫（），数据链路层的PDU叫（）。

PDU

RLCPDU类型包括控制PDU(RLCcontrolPDU)和数据PDU(RLCdataPDU)两种。

认证的类型有消息认证和身份认证，消息认证的目的是证实消息的（）。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

PDU在封装过程中加入的控制信息包含哪三个部分？

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。