What is the main purpose of a modem? Which transmission mode allows data to flow in both directions at the same time? The device used to connect multiple computers within a network is: Which type band

Here are the answers to the questions:

1. What is the main purpose of a modem? A modem (modulator-demodulator) converts digital signals from a computer into analog signals for transmission over communication lines, and converts analog signals back into digital signals for the computer.

   • The correct option is b) Convert digital signals to analog and vice versa.

2. Which transmission mode allows data to flow in both directions at the same time?

   • Simplex allows data flow in one direction only.
   • Half-duplex allows data flow in both directions, but not simultaneously.
   • Full-duplex allows data flow in both directions simultaneously.
   • The correct option is c) Full-duplex.

3. The device used to connect multiple computers within a network is: A switch is a networking device that connects multiple devices (like computers, printers, servers) within the same local area network (LAN) and forwards data only to the intended recipient.

   • The correct option is b) Switch.

4. Which type bandwidth refer to in data communication? In data communication, bandwidth refers to the maximum rate at which data can be transferred over a network connection in a given amount of time.

   • The correct option is b) Speed of data transfer.

5. Which protocol is used to send emails?

   • SMTP (Simple Mail Transfer Protocol) is the standard protocol for sending email messages between servers.
   • HTTP is for web browsing.
   • FTP is for file transfer.
   • TCP is a transport layer protocol, not an application layer protocol for email sending.
   • The correct option is c) SMTP.

6. Which type of d cable is usend emails? This question appears to have a typo and likely refers to a protocol, similar to question 5, given the options. Assuming it asks "Which protocol is used to send emails?", the answer is SMTP.

   • The correct option is b) SMTP.

7. Which type of cable is least affected by electromagnetic interference?

   • Fiber optic cables transmit data using light pulses, making them immune to electromagnetic interference (EMI) that affects electrical signals in copper-based cables (twisted pair, coaxial, copper wire).
   • The correct option is c) Fiber optic cable.

8. (Question 8 is not present in the image.)

9. A router operates at which layer of the OSI model? A router is a device that forwards data packets between computer networks. It makes decisions about where to send data based on IP addresses, which are part of the Network Layer.

   • The correct option is b) Network layer.

10. What is the function of an IP address? An IP (Internet Protocol) address is a unique numerical label assigned to each device connected to a computer network. Its primary function is to identify the device and its location on the network, enabling communication.

    • The correct option is a) Identify a device on a network.