Both bus and tree topologies are characterized by the use of multipoint (1).For the bus, all stations attach, through appropriate hardware (2) known as a tap, directly to a linear transmission medium, or bus. Full-duplex operation between the station and the tap allows data to be transmitted onto the bus and received from the(3). A transmission from any station propagates the length of the medium in both directions and can be received by all other (4). At each end of the bus is a (5) , which absorbs any signal, removing it from the bus.空白（2）处应选择（） A.processing。 switching。 routing。 interfacing。
论网络管理中的灾难备份和容灾技术 由于技术不断的发展和人们对灾难、意外事故的认识越来越深刻。灾难备份和容灾技术方案的可选择性也越来越多。作为信息中心和网络中心的设计人员需要结合自身的条件而采取合适的灾难备份和容灾技术。 请围绕"网络管理中的灾难备份和容灾技术"论题，依次从以下三个方面进行论述。 （1）概要叙述你参与分析和设计的灾难备份方案、采用的容灾技术以及你所担任的主要工作。 （2）深入地讨论在项目中选择灾难备份方案、采用的容灾技术的原则。 （3）详细论述所选择的灾难备份方案、采用的容灾技术，并对之进行详细的评论。
论网络系统的安全设计 网络的安全性及其实施方法是网络规划中的关键任务之一，为了保障网络的安全性和信息的安全性，各种网络安全技术和安全产品得到了广泛使用。 请围绕"网络系统的安全设计"论题，依次对以下三个方面进行论述。 （1）简述你参与设计的网络安全系统以及你所担任的主要工作。 （2）详细论述你采用的保障网络安全和信息安全的技术和方法，并着重说明你所采用的软件、硬件安全产品以及管理措施的综合解决方案。 （3）分析和评估你所采用的网络安全措施的效果及其特色，以及相关的改进措施。
A transport layer protocol has several responsibilities, One is to create a process-to-process (program-to-program) communication; TCP uses port (1) to accomplish this. Another responsibility of a transport layer protocol is to create a (2) and error-control mechanism at the transport level. TCP uses a sliding (3) protocol to achieve flow control. It uses the acknowledgment packet, time-out, and retransmission to achieve (4) control. The transport layer is also responsible for providing a connection mechanism for the application program. The application program sends (5) of data to the transport layer. It is the responsibility of the transport layer at the sending station to make a connection with the receiver.空白（4）处应选择（） A.packet。 time。 error。 phase。
A transport layer protocol has several responsibilities, One is to create a process-to-process (program-to-program) communication; TCP uses port (1) to accomplish this. Another responsibility of a transport layer protocol is to create a (2) and error-control mechanism at the transport level. TCP uses a sliding (3) protocol to achieve flow control. It uses the acknowledgment packet, time-out, and retransmission to achieve (4) control. The transport layer is also responsible for providing a connection mechanism for the application program. The application program sends (5) of data to the transport layer. It is the responsibility of the transport layer at the sending station to make a connection with the receiver.空白（3）处应选择（） A.path。 window。 frame。 diagram。
Both bus and tree topologies are characterized by the use of multipoint (1).For the bus, all stations attach, through appropriate hardware (2) known as a tap, directly to a linear transmission medium, or bus. Full-duplex operation between the station and the tap allows data to be transmitted onto the bus and received from the(3). A transmission from any station propagates the length of the medium in both directions and can be received by all other (4). At each end of the bus is a (5) , which absorbs any signal, removing it from the bus.
空白（1）处应选择（）
