OSI Model — Set 4
Computers · OSI मॉडल · Questions 31–40 of 70
Which layer of the OSI model is responsible for 'Hop-to-Hop' delivery of data?
Correct Answer: D. Data Link Layer
The Data Link Layer manages the reliable transfer of data frames between two directly connected nodes. This is often called hop-to-hop or node-to-node delivery. The Network Layer, by contrast, manages source-to-destination delivery across multiple hops.
At which layer of the OSI model is data converted into signals such as light or radio waves?
Correct Answer: A. Layer 1
The Physical Layer (Layer 1) converts digital bits into the physical signals required by the transmission medium. This can be electrical pulses for copper wires, light for fiber optics, or radio waves for Wi-Fi. It is the only layer concerned with the physics of the connection.
Which layer manages the 'Checkpoints' for long file transfers to prevent starting over after a crash?
Correct Answer: A. Session Layer
The Session Layer inserts synchronization points into the data stream to act as checkpoints. If a network failure occurs during a large transfer, the session can be resumed from the last successful checkpoint. This is particularly useful for large downloads or database updates.
Encryption and decryption are key services provided by which layer?
Correct Answer: C. Presentation Layer
The Presentation Layer handles the encryption of data before it is sent to lower layers to ensure privacy. It also decrypts the incoming data for the application layer on the receiving system. This provides a transparent layer of security for network applications.
Which of the following describes the sequence of layers in the OSI model from top to bottom?
Correct Answer: A. A-P-S-T-N-D-P
The correct order from top (Layer 7) to bottom (Layer 1) is Application, Presentation, Session, Transport, Network, Data Link, and Physical. A common mnemonic for this is 'All People Seem To Need Data Processing'. Knowing this order is fundamental for troubleshooting network issues.
Which layer is responsible for 'Segmentation' of the data stream into smaller units?
Correct Answer: D. Transport Layer
The Transport Layer divides the data received from the Session layer into manageable units called segments. It also adds a header with sequence numbers to each segment to help the receiver reassemble them correctly. This process allows the network to handle data more efficiently.
At which layer of the OSI model does the Internet Protocol (IP) work?
Correct Answer: A. Layer 3
The Internet Protocol (IP) is the primary protocol of the Network Layer (Layer 3). It provides the rules for addressing and routing packets across the network. IP is the foundation upon which the modern internet is built.
Which layer provides 'End-to-End Flow Control' to ensure data is not lost due to congestion?
Correct Answer: C. Transport Layer
The Transport Layer monitors the amount of data being sent and received to prevent network congestion. It can tell the sender to slow down if the receiver's buffer is full. This ensures a reliable flow of data between the two communicating devices.
Which layer is responsible for determining the physical topology of the network, such as Bus or Star?
Correct Answer: D. Physical Layer
The Physical Layer defines how the devices are physically connected to form a network topology. It includes the layout of cables, hubs, and other hardware components. Physical topology is distinct from logical topology, which describes how data actually flows.
Which layer handles the 'Log-in and Log-off' procedures for a network session?
Correct Answer: A. Session Layer
The Session Layer manages the authorization and security protocols required to start a communication session. it handles the login process to verify the user's identity before allowing access. Similarly, it ensures that the session is gracefully closed during log-off.