OSI Model — Set 5
Computers · OSI मॉडल · Questions 41–50 of 70
What is the primary function of the 'LLC' sublayer in the Data Link Layer?
Correct Answer: C. Flow and error control
The Logical Link Control (LLC) sublayer acts as an interface between the Network Layer and the MAC sublayer. It handles flow control, error control, and the identification of protocols in the network layer. This allows the Data Link Layer to support multiple network protocols simultaneously.
Which layer is responsible for 'Source-to-Destination' delivery of a complete message?
Correct Answer: D. Transport Layer
The Transport Layer is responsible for the overall delivery of the entire message from the source application to the destination application. It tracks segments and ensures that they are all received and reassembled correctly. The Network Layer only handles the delivery of individual packets.
Which OSI layer is responsible for the bit-by-bit delivery of data?
Correct Answer: A. Physical Layer
The Physical Layer is purely concerned with the transmission of individual bits over the physical medium. It does not understand the meaning or structure of the data. It ensures that a '1' sent at one end is received as a '1' at the other end.
At which layer are 'Bridges' commonly found in a network?
Correct Answer: C. Data Link Layer
Bridges operate at the Data Link Layer to connect two separate network segments into a single logical network. They use MAC addresses to filter traffic and reduce congestion by only forwarding necessary data. Modern switches have largely replaced simple bridges in local area networks.
Which layer is responsible for 'Token Management' to prevent data collisions?
Correct Answer: D. Session Layer
The Session Layer provides a mechanism for token management to control whose turn it is to perform a certain action. This is crucial in networks where devices share a common medium and need to avoid sending data at the same time. it essentially coordinates the dialogue between systems.
The 'ICMP' protocol used for diagnostics like 'Ping' operates at which layer?
Correct Answer: D. Network Layer
The Internet Control Message Protocol (ICMP) is a vital part of the Network Layer. It is used by network devices to send error messages and operational information. Tools like 'ping' and 'traceroute' rely on ICMP to test network connectivity.
Which layer of the OSI model is responsible for providing 'Translation' between different character sets?
Correct Answer: D. Presentation Layer
The Presentation Layer translates data between the format used by the application and the standard network format. This includes converting between character sets like ASCII and EBCDIC. This ensures that computers with different internal representations can still exchange information.
Data units at the Data Link Layer are commonly called?
Correct Answer: A. Frames
A 'Frame' is the protocol data unit at the Data Link Layer. It consists of the payload from the Network Layer wrapped in a header and a trailer. Frames are the units of data that are physically transmitted between local network nodes.
Which layer is responsible for 'Congestion Control' within a single network subnet?
Correct Answer: D. Network Layer
The Network Layer implements strategies to manage and reduce congestion across the entire network. It can use techniques like load balancing or dropping low-priority packets during peak traffic. Congestion control at this layer focuses on the health of the routers and links.
What is the standard unit of data at the Transport Layer?
Correct Answer: B. Segment
A 'Segment' is the data unit at the Transport Layer when using TCP. When using the connectionless UDP protocol, it is often referred to as a 'Datagram'. Segments contain port numbers and sequence information necessary for end-to-end delivery.