Govt. Exams
Entrance Exams
The Physical Layer (Layer 1) handles the conversion of data into physical signals (electrical, optical, or radio waves) and manages the hardware transmission of bits over the network medium.
The Network Layer (Layer 3) uses IP addresses to route packets across different networks.
A switch operates at the Data Link Layer (Layer 2) using MAC addresses to forward frames within the same network segment.
The Session Layer (Layer 5) establishes, maintains, and terminates connections between applications, managing the conversation flow.
The Physical Layer (Layer 1) deals with the transmission of raw bits over physical media like copper wires, fiber optics, or radio waves.
IP addresses (source and destination) are added at the Network Layer (Layer 3). This happens when the Network Layer encapsulates transport layer segments into IP packets.
The Physical Layer (Layer 1) is responsible for the actual physical transmission media including cables, connectors, voltage levels, and signal transmission. Cable issues are Layer 1 problems.
The Transport Layer (Layer 4) encapsulates data from the Application Layer into segments (TCP) or datagrams (UDP) with port numbers and reliability information.
The Session Layer (Layer 5) manages session establishment, maintenance, and termination. It handles dialog control between communicating devices.
TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) operate at Layer 4, the Transport Layer. TCP is connection-oriented while UDP is connectionless.