WLANs are increasingly popular because they enable...

第1题

To effectively eliminate MAI in mobile systems, __________ channel codes are usually used in CDMA systems.

第2题

Grid systems are important to locational analysis because they allow one to analyze spatial relationships with relatively simple mathematical tools.

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第3题

选出应填入下面一段英语中______内的正确答案。

WLANs are increasingly popular because they enable cost-effective connections among people, applications and data that were not possible, or not cost-effective, in the past. For example, WLAN-based applications can enable fine-grained management of supply and distribution(1)to improve their efficiency and reduce(2). WLANs can also enable entirely new business processes. To cite but one example, hospitals are using WLAN-enabled point-of-care applications to reduce errors and improve overall(3)care. WLAN management solutions provide a variety of other benefits that can be substantial but difficult to measure. For example, they can protect corporate data by preventing(4)through rogue access points. They help control salary costs, by allowing IT staffs to manage larger networks without adding staff. And they can improve overall network management by integrating with customers' existing systems, such as OpenView and UniCenter. Fortunately, it isn't ne essary to measure these benefits to justify investing in WLAN management solutions, which can quickly pay for themselves simply by minimizing time-consuming(5)and administrative chores.

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第4题

（73）

A.transportations

B.applications

C.connections

D.translations

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第5题

下面关于IPv6的描述中，最准确的是（）。

A. IPv6可以允许全局IP地址重复使用

B．IPv6解决了全局IP地址不足的问题

C．IPv6的出现使得卫星联网得以实现

D. IPv6的设计目标之一是支持光纤通信

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第6题

Border Gateway Protocol(BGP) is inter-autonomous system (71) protocol. BGP is based on a routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomous system routing because there are occasions on which the route with the smallest (72) count is not the preferred route. For example, we may not want a packet through an not secure even though it is the shortest route. Also, distance vector routing is unstable due to the fact that the routers announce only the number of hop counts to the destination without actually defining the path that leads to that (73) ．A router that receives a distance vector advertisement packet may be fooled if the shortest path is actually calculated through the receiving router itself. Link (74) routing is also not a good candidate for inter-autonomous system routing because an Internet is usually too big for this routing method. To use link state routing for the whole internet would require each router to have a huge link state database. It would also take a long time for each router to calculate its rousting (75) using the Dijkstra algorism.

（71）

A. routing

B. switching

C. transmitting

D. receiving

（72）

A. path

B. hop

C. route

D. packet

（73）

A. connection

B. window

C. source

D. destination

（74）

A. status

B. search

C. state

D. research

（75）

A. table

B. state

C. metric

D. cost

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第7题

(接上一题)用户端需要CABLE Modem，它提供的连接是 (52) 。

A.无连接

B.虚拟

C.临时

D.永久

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第8题

根据《综合布线系统工程设计规范GB50311-2007))相关规定，综合布线系统水平缆线与建筑物主干缆线及建筑群主干缆线之和所构成信道的总长度不应大于 () M.

A.90

B.100

C.650

D.2000

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第9题

在ARP工作过程中，请求包和应答包分别采用的传输方式是 () 。

A.单播、单播

B.广播、广播

C.单播、广播

D.广播、单播

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● WLANs are increasingly popular because they enable cost-effective connections among peop