软件水平考试
Networks can be interconnected by different devices.In the physical layer, networks can be connected by（ ） or hubs, which just move the bits from one network to an identical network.A.repeaters B.relays C.connectors D.modems
题目
B.relays
C.connectors
D.modems
相似问题和答案
第1题：
How could the Ezonexam corporation benefit from using VLANs on their network?
(Select three answer choices.)
A. VLANs allow access to network services based on department, not physical location.
B. VLANs utilize packet filtering to enhance network security.
C. VLANs provide a low-latency, high bandwidth internetworking alternative.
D. VLANs provide a method of communication between IP addresses in large networks.
E. VLANs establish segmented broadcast domains in switched networks.
F. VLANs can greatly simplify adding, moving, or changing hosts on the network.
A,E,F 解析：Explanation:
VLANs establish broadcast domains in switched networks, so by virtue of having the option to create many efficient broadcast domains, congestion is reduced and network throughput is greatly enhanced. VLANs allow networks to be divided by department or resource needs, rather then by physical location. When people move departments, leave a department, or join a department, administration is easy and convenient with a few keystrokes.
Incorrect Answers:
B, D. These would be router functions at layer 3. Switches and VLANs operate at layer 2 of the OSI model.
C. The use of VLANs may actually increase the latency in some cases, as traffic from one VLAN to the other will need to be routed.
第2题：
Networks can be interconnected by different devices in the physical layer networks can be connected by (71) or hubs．which just move the bits from one network to an identical network．One layer up we find bridges and switches which operate at data link layer．They can accept (72) ，examine the MAC address and forward the frames to a different network while doing minor protocol translation in the process in me network layer，we have routers that can connect two networks，If two networks have (73) network layer，the router may be able to translate betweenthe packer formats．In the transport layer we find transport gateway，which can interface between two transport connections Finally，in the application layer，application gateways translate message (74) ．As an example，gateways between Internet e-mail and X，400 e-mail must (75) thee-mail message and change various header fields．
(68)
A．reapers
B．relays
C．packages
D．modems
第3题：
●LANs can be connected by using bridges，which operate in the (67) .
(67) A．data-link layer
B．Physical layer
C．network layer
D．transport layer
【解析】译文：局域网可以使用网桥连接起来，它在数据链路层操作。
第4题：
Which one of the following characteristics is true regarding the use of hubs and switches?
A．Hubs can have their ports be configured with VLANs
B．Using hubs is costly with regard to bandwidth availability.
C．Switches can not forward broadcasts.
D．Switches are more efficient than hubs in processing frames.
E．Switches increase the number of collision domains in the network.
解析：Explanation:Switchesincreasesthenumberofcollisionsdomainsinthenetwork.SwitchesthatareconfiguredwithVLANswillreducethesizeofthecollisiondomainsbyincreasingthenumberofcollisiondomainsinanetwork,butmakingthemsmallerthanthatofonebig,flatnetwork.IncorrectAnswers:A.SwitchesarecapableofVLANconfigurations,buthubsarenot.B.Hubsaregenerallytheleastcostlymethodpossibletoconnectmultipledevicestogetherinanetwork.C.Switchesforwardbroadcastsandmulticasts,bydefault,toallportswithinthesameVLAN.Onlyroutersblockallbroadcasttrafficbydefault.D.Switchesandhubscanbeequallyefficientinprocessingframes,intheory.Inpractice,switchesaregenerallymoreefficientastheyusuallyhavemoreCPUandmemoryallocatedtothem,andaregenerallymuchmoreexpensivethanasimplehub.
第5题：
The IP network 210.106.14.0 is subnetted using a /24 mask. How many usable networks and host addresses can be obtained from this?
A．1 network with 254 hosts
B．4 networks with 128 hosts
C．2 networks with 24 hosts
D．6 networks with 64 hosts
E．8 networks with 36 hosts
解析：Explanation:Asubnetwith24bitsonwouldbe255.255.255.0.SincethisisaclassCnetwork,thissubnetcanhaveonly1networkand254usablehosts.
第6题：
●Networks can be interconnected by different devices．In the physical layer，networks can be connected by (66) or Hubs，which just move the bits from one network to an identical network．One layer up we find bridgas and swiehes,which operate at data link layer．They can accept (67) ，examine the MAC address，and forward the frames to a different network while doing minor protocol translation in the process．In the network layer，we have routers that can connect two netwoks．If two networks have (68) network layer，the router may be able to translate between the packet formats．In the transport layer we find transport gateway，which can interface between the two transport connections．Finally，in the application layer，application gateways translate message (69) ．As an example，gateways between Internet e-mail and X．400 e-mail must (70) the e-mail message and change various header fields．
(66) A．reapers
B．relays
C．connects
D．modems
(67) A．frames
B．bytes
C．packages
D．cells
(68) A．special
B．dependent
C．similar
D．dissimilar
(69) A．syntax
B．semantics
C．languages
D．format
(70) A．analyze
B．pairs
C．delete
D．create
【解析】网络可以用不同的设备互联。在物理层，用中继器或者集线器互联，这些设备只是在相同的网络之间传送比特串。在上面的数据链路层，可以使用网桥或者交换机，这些设备接收数据帧，检查MAC地址，并可以实现少量的协议转换，把数据帧转发到不同的网络中。在网络层，使用路由器连接两个网络。如果两个网络的网络层不同，路由器能够对分组格式进行转换。在传输层，使用传输网关，它可以在两个传输连接之间建立接口。最后，在应用层，应用网关实现消息语法之间的翻译。例如，在Internet邮件和X．400邮件之间的网关可以对邮件报文进行语法分析，对报文的各个头字段做出改变。
第7题：
Networks can be interconnected by different devices. In the physical layer, networks can be connected by(66)or hubs, which just move the bits from one network to an identical network. One layer up we find bridges and switches, which operate at data link layer. They can accept(67), examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two networks. If two networks have(68)network layer, the router may be able to translate between the packet formats. In the transport layer we fmd transport gateway, which can interface between two transport connections. Finally, in the application layer, application gateways translate message(69). As an example, gateways between Internet e-mail and X.400 e-mail must(70)the e-mail message and change various header fields.
A．repeaters
B．relays
C．connectors
D．modems
解析：网络可以用不同的设备互连。在物理层，用中继器或集线器互连，这些设备只是在相同的网络之间传关比特串。在上面的数据链路层，可以使用网桥或交换机，这些设备接收数据帧，检查MAC地址，并可以实现少量的协议转换，把数据帧转发到不同的网络中。在网络层，我们使用路由器连接两个网络。如果两个网络的网络层不同，路由器能够对分组格式进行转换。在传输层，我们使用传输网关，它可以在两个传输连接之间建立接口。最后，在应用层，应用网关实现消息语法之间的翻译。例如，在Internet邮件和X.400邮件之间的网关可以对邮件报文进行语法分析，对报文的各个报头字段做出改变。
第8题：
LANs can be connected by using bridges, which operate in the
A．physical layer
B．data link layer
C．network layer
D．transport layer
第9题：
A.PAT
B.NAT
C.Multicast
D.Subnetting
第10题：
A.Switches take less time to process frames than hubs take.
B.Switches do not forward broadcasts.
C.Hubs can filter frames.
D.Using hubs can increase the amount of bandwidth available to hosts.
E.Switches increase the number of collision domains in the network.