TCP and UDP are transport layer protocols; the OSI layer is layer 4 (transport)
TCP is in the transport layer.
IP is in the network layer.
Transport layer -->TCP,UDP
TCP is a layer 4 (transport) protocol.
Hubs and repeaters operate at the Physical Layer of the OSI Model. The Physical Layer is the first layer of the OSI Model.
According to Cisco Curriculum Semester 4 1.2.1.1 As described in relation to the OSI reference model, WAN operations focus primarily on Layer 1 and Layer 2. WAN access standards typically describe both Physical layer delivery methods and Data Link layer requirements, including physical addressing, flow control, and encapsulation.
Layer 3
Network Layer
TCP, the Transmission Control Protocol, is a layer-4 protocol (in the 7-layer OSI model).
1. Repeaters (Operate at the OSI Physical Layer).2. Bridges (Operate at the OSI Data Link Layer).3. Routers {and Brouters} (Operate at the OSI Network Layer).
TCP operates at transport layer
Hubs are a physical layer (layer 1) device; most switches operate at the Data Link layer (Layer 2) of the OSI model.
UDP or User Datagram Protocol works on the Transport Layer (layer 4) in the OSI model.
Hubs and repeaters operate at the Physical Layer of the OSI Model. The Physical Layer is the first layer of the OSI Model.
The Application layer The Presentation layer The Session layer
A firewall generally works at layer 3 and 4 of the OSI model. Layer 3 is the Network Layer where IP works and Layer 4 is the Transport Layer, where TCP and UDP function. Many firewalls today have advanced up the OSI layers and can even understand Layer 7 - the Application Layer.
TCP/IP because the osi model has seven layer but in tcp/ip only four layers and most important is that the tcp/ip model is reduce the function of osi model.
Layer 3
According to Cisco Curriculum Semester 4 1.2.1.1 As described in relation to the OSI reference model, WAN operations focus primarily on Layer 1 and Layer 2. WAN access standards typically describe both Physical layer delivery methods and Data Link layer requirements, including physical addressing, flow control, and encapsulation.
The data-link layer The physical layer
3