Encapsulation: each layer adds its own header and sometime a trailer as well to the data when the data is sent from the source
Decapsulation: each layer removes its own header as the data gets passed through each layer after it reaches its destination
each layer works independently from the other layers and uses pre defined interfaces to communicate with eachother. and this modularity lets the whole thing be really efficient
Differences:
the obvious first difference is the differing amount of layers in each model ig
the OSI model is more of a theoretical one. used to understand and design networks while the TCP-IP model is a more practical suite of protocols and stuff that can be used in the real world. it forms most if not all of the internet :3
the OSI model was developed by ISO (international organization for standardization) as a generic reference model while the TCP-IP model was developed by the US department of defense for robust and scalable communication
heres a neat table i copy pasted:
OSI Model
TCP/IP Model
OSI stands for Open Systems Interconnection.
TCP/IP stands for Transmission Control Protocol/Internet Protocol.
OSI model has 7 layers.
TCP/IP model consists of 4 layers.
Package delivery is guaranteed in OSI Model.
Package delivery is not guaranteed in the TCP/IP Model.
In the OSI model, only layers 1,2 and 3 are necessary for data transmission.
All layers of the TCP/IP model are needed for data transmission.
Protocols at each layer is independent of the other layer.
Layers are integrated; some layers are required by other layers of TCP/IP model.
OSI Model is a conceptual framework, less used in practical applications.
Widely used in actual networks like Internet and Communication Systems.