1. Networking Exercise Short Questions Answers
1. (a) 衞星寬頻和微波寬頻
Satellite broadband and microwave broadband
(b) 中學學校的網絡和家居辦公室的網絡
The network of a secondary school and The network of a home office
(c) 國際貨運公司的網絡，它連接了位於超過 30 個國家的所有貨倉內的局部區域網絡
國家超市企業的網絡，它連接了位於超過 20 個城市的所有分店內的局部區域網絡
The network of a worldwide delivery company that connects the LANs of the warehouses
in more than 30 countries
The network of a national supermarket enterprise that connects the LANs of the stores in
more than 20 cities
2. (a) 優點：
● 數據中央化，從而更易管理，用戶的存取更具效率。
Data is centralized for easier management and more efficient user access.
● 保安中央管控，可以更有效率地管理。
Security is controlled in a centralized manner that can be managed more efficiently.
缺點：
● 裝設費用較高，因為伺服器通常需要較高階的硬件。
The set-up cost is higher since servers need more advanced hardware usually.
● 需要較多技術知識來建立和維護伺服器。
More technical knowledge is required to set up and maintain servers.
(b) 集線器和交換器
Hub and switch
3. (a) 檔案/資訊、硬件和應用軟件
File / information, hardware and application software
(b) 內部通訊
Internal communication
(c) UTP 電纜和無線局部區域網絡
UTP cables and Wireless LAN
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2. 4. (a) (i) 同軸電纜 Coaxial Cables
(ii) RJ-45 電纜 RJ-45 Cables
(b) (i) PCI 和 USB
(ii) PCMCIA 和 USB
5. (a) 實體位址和硬件位址
Physical address and hardware address
(b) MAC 位址包含 6 個兩位的十六進制數字。
A MAC address consists of six 2-digit hexadecimal numbers.
每個設備的 MAC 位址都應是獨一的。
The MAC address of each piece of equipment should be unique.
(c) 網絡界面卡和交換器
Network interface card and switch
6. (a) (i) UTP 電纜和 STP 電纜
UTP cables and STP cables
(ii) 各 STP 電纜均的四組雙扭線電纜外面均有金屬外殼 而 UTP 電纜則沒有這些金
，
屬外殼。
Each STP cable has a metal wrapper around the four twisted-pairs of wire. It is
absent in UTP cables.
(iii) 金屬外殼可用於減少電磁干擾。
The metal wrapper is used to reduce the electromagnetic interference.
(b) 光纖電纜和同軸電纜
Optical fibre cables and coaxial cables
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3. 7. (a) 優點：
● 有線網絡的數據傳輸速度較高。
The data transmission speed of a wired network is higher.
● 有線網絡的可靠性較高。
The reliability of a wired network is higher.
缺點：
● 有線網絡的裝設費用通常較高。
The set-up cost of a wired network is higher usually.
● 對於流動設備而言，有線網絡較不方便。
It is not convenient for mobile devices.
(b) (i) 802.11g
(ii) 相同
8. (a) (i) 上載頻寬遠遠小於下載頻寬。
The upload bandwidth is much smaller than the download bandwidth.
(ii) 對稱數碼用戶線（SDSL）和電纜調制解調器
SDSL and cable modem
(b) T 載波 T-carrier
(c) 藍牙和紅外線 Bluetooth and Infrared
9. (a) 局部區域網絡 Local area network (LAN)
(b) 雙扭線電纜/同軸電纜 Twisted pair/coaxial cables
(c) 光纖電纜 Optic fibre cables
(d) 寬廣區域網絡 Wide are network (WAN)
(e) 軟件共用和視像會議 Software sharing and video conferencing
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4. 10. (a) (i) 表示層 Presentation
(ii) 傳輸層 Transport
(iii) 數據鏈路層 Data link
(iv) 實體層 Physical
(b) 檔案傳輸協定（FTP）和簡單郵件傳輸協定（SMTP）
File Transfer Protocol and Simple Mail Transfer Protocol
11. (a)
OSI 模型的通訊層 數據塊
OSI Model Layer Data Block
傳輸層 (i) 數據報 Datagram
Transport
網絡層 (ii) 數據包 Packet
Network
數據鏈路層 (iii) 幀 Frame
Data Link
(b) (i) 傳輸表頭 Transport Header
(ii) 網絡表頭 Network Header
(iii) 數據鏈路表頭/數據鏈路表尾 Data Link Header/Data Link Trailer
12. (a) 首先，若我們一次過傳輸整個檔案，只要傳輸過程有任何錯誤，便需要重新傳輸過
整個檔案。相反，若先將檔案分割成數據包，就只需要重新傳送損壞或遺失的數據
包。
Firstly, if a file was sent in one transmission, the whole file would be needed to be resent
even if there was just one transmission error. However, if the file was divided into packets,
only the corrupted or missing packet would be needed to be resent.
此外，若我們一次過傳輸一個大型檔案，便會長時間佔用傳輸媒介；其他電腦需要
等待一段時間，才可以開始它們的傳輸。
Also, if a large file was sent in one transmission, the transmission medium would be
occupied for a long time and the other machines would require to wait for a long time to
start their transmissions.
(b) (i) 傳輸層 Transport layer
(ii) 傳輸控制協定 Transmission control protocol（TCP）
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5. 13. (a) 傳輸控制協定/互聯網協定 Transmission control protocol/Internet protocol（TCP/IP）
(b) 用戶數據包協定/互聯網協定 User Datagram Protocol/Internet Protocol（UDP/IP）
即時視像傳輸（例如視像會議）Real-time video transfer (e.g. video conferencing)
(c) 優點： UDP 所用的處理時間較 TCP 為短。
UDP requires less processing time than TCP.
缺點： UDP 不能追蹤數據包在每次傳輸過程中的位置，而 TCP 則有此功能。
UDP does not keep track of the packets in every transmission while TCP does.
UDP 的回應（處理）時間較短，即使偶然會有數據幀丟失，仍能滿足視像會議的需
要。
Short response (processing) time of UDP is more important in video conferencing when
compared to its occasional frame drops.
14. (a)
通訊種類 傳輸信息種類
Type of communication Type of message transmitted
(i) 聊天室 Chat room 一對多的即時信息
One-to-many instant messages
(ii) 網絡電話 Internet phone 實時的流式音頻信息
Real-time streamed audio messages
(iii) 視像會議 Video conferencing 實時的流式視像信息
Real-time streamed video messages
(b) 網頁瀏覽器、新聞組、討論區 Web browser, Newsgroup, Discussion forum.
15. (a) 該檔案幀會重新組合為相應的數據包，並傳送至網絡層。
The frames will be reassembled into the corresponding packets that will be passed to the
network layer.
(b) 該數據包會重新組合為相應的數據報，並傳送至傳輸層。
The packets will be reassembled into the corresponding datagrams that will be passed to
the transport layer.
(c) 該數據報會重新組合為相應的檔案，並傳送至話路層（或應用層）。
The datagrams will be reassembled into the corresponding file that will be passed to the
session layer (or the application layer).
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6. 16. 完成以下與 IP 位址分級有關的表。
Complete the following table regarding the classification of IP addresses.
每個網址可供使用的主機數目
級別 在二進制中首個八位字節的起始數字
Number of hosts available for each
Class First octet (in binary) begins with
network address
0 16777214
A
10 65534
B
110 254
C
17. (a) 一般頂級域，例如「com」Generic-code TLD, example: .com
國家碼頂級域，例如「hk」Country-code TLD (1), example: .hk
(b) (i) 劃一資源定位的其中一個部分是網域名稱。
One component of a URL is domain name.
(ii) 網域名稱系統伺服器將網域名稱翻譯為對應的 IP 位址。
A DNS server translates a domain name into the corresponding IP address.
18. 全部無效 All are invalid
(a) IP 位址應包含四個 8 位元的數字，但這個 IP 位址只有三個 8 位元的數字。
An IP address should consist of four 8-bit numbers, but there are three 8-bit numbers only.
(b) 每個 8 位元數字的數值應在 0 至 255 之間。
Each 8-bit number should have a decimal value range from 0 to 255.
(c) IP 位址應包含四個 8 位元的數字，但此處有五個 8 位元的數字。
An IP address should consist of four 8-bit-numbers, but there are five 8-bit numbers.
19. (a) (i) 它是一個位於香港，並名為 HKU 的教育機構的網站。
It is the web site of an educational institution in Hong Kong with the name HKU.
(ii) 它是一個中華人民共和國政府的網站。
It is the web site of the government of the People’s Republic of China.
(b) www.sony.com.cn
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7. 20. (a) 因為 IP 位址是無意義和難以記憶的，所以人們為網絡上的主機設定一個網域名稱，
方便識別。
A domain name is given to a host for easy identification since IP address is meaningless
and difficult to remember.
(b) 網域名稱系統將網域名稱翻譯成對應的 IP 位址，或把 IP 位址翻譯成對應的網域名
稱。
A domain name system is used for translating the domain names into corresponding IP
addresses, or vice versa.
(c) 是，一個網站可以透過它的 IP 位址來識別及存取。
Yes. A web site can be identified and accessed by its IP address.
(d) 否，一個網站必須透過一個 IP 位址來識別及存取。
No. A web site must be identified by an IP address in order to access it.
21. (a) IP
(b) TCP
(c) TCP
(d) TCP
(e) IP
(f) IP
22. ● 蜘蛛查詢器程序 Spider program
它可用來在互聯網上搜尋資訊的程序。
It is a program used to search for information on the Internet.
● 數據庫管理系統 Database management system
它可用來貯存蜘蛛查詢器所找到的資訊。
It is used to store information searched by the spiders.
● 輸入處理程序 Access program / user interface program
可用來接收用戶要求和從數據庫提取相關的結果。
It is a program used to receive user requests and retrieve the corresponding results from
the database.
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8. 23. (a) 在互聯網上傳輸檔案。To transfer files on the Internet
(b) 伺服器和客戶 Server and client
(c) ● 任何人都可從支援匿名登入的 FTP 伺服器下載某些檔案。
Anyone can download certain files from an FTP server that supports anonymous
login.
● 用戶可以「anonymous」作為用戶名，並以其電子郵件地址作為密碼。
A user can log onto the FTP server using ‘anonymous’ as the username and his / her
e-mail address as the password.
24.
符號 / 運算符 描 述
Symbol/Operator Description
AND
NOT
OR
萬用符 Wildcard
引號內的語句必須按所指定的次序出現。
The phrase enclosed in the quotation marks must be included in the same
specified order.
必須不包括符號後的關鍵字。
The keyword after the symbol must be excluded.
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9. 25. (a) 傳統商貿的廣告是靠電視、報紙等作為媒介的，而電子商貿的廣告則是在網站上展
示的。
The advertisements of conventional commerce are broadcasted through TV, newspapers
and so on, while those of e-commerce are put on web sites.
(b) 在傳統商貿的模式中，顧客透過電話或傳真下訂單，而在電子商貿模式中，顧客則
利用網上表單下訂單。
In conventional commerce, orders are placed via phone or fax while online forms are used
in e-commerce.
(c) 傳統商貿的交易在商店或辦公室等地方進行，而電子商貿則在互聯網上進行。
Transactions of conventional commerce are done at places such as shops, stores, and
offices while those of e-commerce are done through the Internet.
26. (a) 優點：
● 電子商貿為賣家提供開拓環球市場的機會。
E-commerce allows sellers to gain access to global markets.
● 由於不需要辦公室和銷售人員，可以大大降低成本。
Since offices and salespersons are not required, huge costs can be reduced.
缺點：
● 賣方需要建立和維護電子商貿網站。
Sellers need to build and maintain e-commerce web sites.
● 向傳統保守的顧客推廣電子商貿並不容易。
It is difficult to promote e-commerce web sites to traditional customers.
(b) 優點： 在互聯網上尋找罕有物品較為容易。
It is easier to find rare items on the Internet.
缺點： 買家可能需要繳付運費和等候送貨。
Buyers may need to pay for shipping and wait for delivery.
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10. 27. (a) 優點：
● 由於不需印製教材，大批學生也可透過電腦使用相同的網上學習教材，因此，
電子學習的成本效益相當高。
It is cost-effective as online course materials can be used by a lot of students through
computers without printing them out.
● 學生可學到最新的知識。
It allows just-in-time knowledge acquisition.
● 可提供到即時評估和回饋。
It allows immediate assessments and feedbacks.
缺點：
● 不適用於需要學生團隊合作、分組討論或與人相處的課程。
It is not suitable for courses that require teamwork, group discussion or human
contact.
(b) 網上遊戲和網上電台 Online games and Internet radio
28. (a) 不需運送費用（例如：郵票）。
No delivery cost (e.g. stamp) is required.
傳送電子郵件只需極短的時間。
E-mails can be delivered in a very short time.
電子郵件可在任何時間同時傳送給多個收件人。
E-mails can be sent at any time and to a large group of people simultaneously.
(b) 用戶不需待整個視像檔案下載完畢便可播放視像。
The entire video file does not need to be downloaded before the user plays it.
在播放已下載的部分時，視像伺服器會同時傳送剩餘的部分，直至下載完畢。
When the downloaded portion is playing, the video server sends the rest portion
simultaneously until the video file ends.
(c) 外掛程序是一個整合在指定軟件上以提供額外功能的小型程序。
A plug-in is a program used to extend the functions of specific software.
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11. 29. (a)
寄件人 收件人
互聯網
Sender X Y Receiver
Internet
X: 發送郵件伺服器 Outgoing mail server
Y: 接收郵件伺服器 Incoming mail server
(b) (i) POP3/IMAP
(ii) SMTP
(c) 許多網絡郵件都包含多餘的廣告。Many webmails include unwanted advertisements.
在一般情況下，用戶在存取網絡郵件時，都需要保持連線。
Many webmails require users to stay online whenever the mails are accessed.
30. (a) 它防止用戶修改文件。
It prevents users from modifying the document.
(b) 網上作業、網上討論區和網上測驗 Online assignment, online forum and online test
(c) 優點： 可在家中學習/可按自己的進度學習
Each student can learn at home and can learn according to one’s pace.
缺點： 欠缺師生之間的互動
There are fewer interactions between students and teachers.
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