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A modem connects a computer to the Internet using telephone lines. It combines the modulation and
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demodulation functions by transforming a digital signal to an analog signal and vice-versa.
Routers are used for connecting various networks. A router may be used to interconnect several networks,
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possibly having different topologies.
A gateway connects the networks that use different protocols. Thus, a gateway may be thought of as a router
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with protocol conversion software.
Solved Exercise
A. Multiple Choice Questions
1. The devices on the network are connected to each other via _________.
a. Transmission Media b. keyboard c. Computer d. Mouse
2. Which device is also known as an intelligent hub?
a. Switch b. Hub c. Router d. Gateway
3. Which of the following can be a node in a network?
a. RJ45 b. Printer c. Data d. Cable
4. Which network device broadcasts the message received to all nodes in the network?
a. Router b. Hub c. Repeater d. Switch
5. Which of the following can be used for communication through a standard modem?
a. Cable lines
b. Telephone lines
c. Both A and B
d. None of the above
B. State whether the following statements are True or False:
1. Each participating node in a network has a unique MAC address. _________
2. In a mesh topology, every node is directly connected to every other node. _________
3. Bus topology uses a common backbone cable to connect all devices in the network. _________
4. Bus topology requires terminators at both ends of the network to avoid signal reflections. _________
5. Star topology relies on a single point of failure at the central hub or switch. _________
C. Fill in the blanks.
1. In _________ topology, all nodes are connected to a central device.
2. A collection of interconnected nodes that communicate via some channel is a _________.
3. A _________ is a discussion forum where users of related interest can post information and reply to others’ posts.
4. Devices in tree topology are connected in a _________ structure.
5. A _________ card provides wireless connectivity and is used to form wireless LANs.
6. A _________ can alternatively be defined as a router with protocol conversion software.
D. Answer the following questions:
1. Give any two applications of computer networks.
Ans. Collaborative learning and research, video-conferencing, online gaming, e-shopping, e-governance.
2. What is data communication?
Ans. Data communication is the exchange of data between two or more networked devices.
238 Touchpad Informatics Practices-XII

