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Network
OSI Model
The OSI (Open System Interconnect) Model was developed in 1984 as an open standard to promote network interconnection and interoperability.
| Layer | Function | Examples |
|---|---|---|
| 7. Application | Support for applications | HTTP, FTP, SMTP (email) |
| 6. Presentation | Protocol conversion, data translation | ASCII, JPEG, etc. |
| 5. Session | Establishes, manages and terminates sessions | NFS, SQL |
| 4. Transport | Ensures Error Free packets | TCP, UDP |
| 3. Network | Provides routing | IP, IPX |
| 2. Data Link | Provides for the flow of data | MAC |
| 1. Physical | Signals and media | cables and NIC |