OSI – Application, Presentation, Session, Transport, Network, Data Link, Physical
TCP/IP – Application, Presentation, Transport, Internet, Network Interface
Physical – Defines the electrical and Physical apps.
Data Link – Detects/corrects errors found at physical. Defines layer 2 protocols to establish and terminate a connection between two physically connected devices.
Network – Provides for logical network addressing, arp, to resolve layer 3 ip address to layer 2 mac ethernet address on lans.
Transport – Controls reliability of communication flow control mechanisms, TCP, for reliability, UDP for unreliability
Session – Controls connection between two systems it establishes, manages, and terminates connection between local and remote systems.
Presentation – layer ensures that network formats are converted in a way that application layer can understand them.
Application – services for end user apps so that communication with another app across network is effective
Data and header info are built at each of the layers.
Segments – Application
Packets – Presentation
Frames – Transport
Bits – Network Interface