Layer 4 usually uses segments, layer 3 are packets, layer 2 are frames. Layer 4 uses either tcp (SYN and ACKS) and UDP (connectionless) with port numbers
Layer 3 i.e, network layer of the OSI model is used to IP addressing.
Networking layer of the OSI model
DHCP runs at the application layer of the OSI model.
Primarily at layer 1 and 2. The frame adds this information for these layers.
Layer 3 (network layer).
The Physical layer is responsible for the actual hardware connection. The physical addressing is handled by the Data Link Layer.
Data Link
physical addressing media access control
The OSI model has seven layers whereby each layer has its function. The Data Link Layer is responsible for addressing data messages so that they reach their destination correctly.
Only the Network Layer (Layer 3) portion of the datagram is used by the Network Layer (Layer 3) portion of the TCP/IP Model. The network portion of the datagram includes IP Addressing information, and things such as TTL (Time to Live), and Datagram Priority markings.
Core, Distribution, and Access.
Physical and MAC addressing are found in the OSI layer 2?