Unit II - Data transmission (IGCSE) -key terms

What is packet switching?

• A method of transmission in which a message is broken into many data packets which can then be sent along pathways independently of each other.

• A technique used to send data in a continuous stream without breaking it into smaller packets.

• A process of encoding data to ensure secure transmission over a network.

• A method of routing data that relies on a single dedicated path for the entire message.

What is an eavesdropper?

• A type of malware that infects computers.

• Another name for a hacker who intercepts data being transmitted on a wired or wireless network.

• A software used to enhance network security.

• A device that boosts Wi-Fi signals.

What is a packet trailer?

• The part of a data packet that indicates the end of the data packet and includes the cyclic redundancy check (CRC) for error checking.

• The initial segment of a data packet that contains the source address.

• A type of network protocol used for data transmission.

• The section of a data packet that holds the payload data.

What does skewed data mean?

• Data that arrives at the destination with the bits no longer synchronized.

• Data that is evenly distributed across all categories.

• Data that has been altered to fit a specific model.

• Data that is collected from a biased sample.

What is the hop number in a data packet header?

• A number used to stop data packets that never reach their destination from clogging up the data paths/routes.

• A measure of the distance a data packet travels in a network.

• The total number of packets sent in a network session.

• A unique identifier for each data packet in a network.

What is ciphertext?

• A type of plaintext message that is easily readable.

• Encrypted data that is the result of putting a plaintext message through an encryption algorithm.

• A method of data compression for large files.

• A digital signature used for authentication.

What is half-duplex data transmission?

• Data that can be sent in both directions but not at the same time.

• Data that can only be sent in one direction at a time.

• Data that can be sent in both directions simultaneously.

• Data that is transmitted without any errors.

What is an echo check?

• A method used to check if data has been transferred correctly; data is sent to a receiver and then immediately sent back to the sender.

• A technique for measuring the speed of sound in different mediums.

• A process for verifying the integrity of a network connection by sending a ping.

• A method for compressing data before transmission.

What is simplex data transmission?

• Data that can be sent in one direction only.

• Data that can be sent in both directions simultaneously.

• Data that can be sent in both directions but not at the same time.

• Data that is transmitted with error correction.

What is a check digit?

• An additional digit appended to a number to check if the entered number is error-free.

• A digit that indicates the total number of digits in a number.

• A digit used to represent a specific value in a number system.

• A digit that is randomly generated to ensure uniqueness.