A network protocol describes a style of communication over a network, and are foundational to the way the modern Internet works. There are many protocols: like for sending email, receiving email, blogging, sharing files, text/instant communication.
The layered network model is an important abstraction for network programming. In this model, the programmer can write software without thinking about how the data is physically transmitted because it’s taken care of at lower levels. In other words, the hardware and network topology is not relevant to the programmer.
The ISO reference layered network model has the following layers:
- Application — supports networked applications.
- Presentation — allows applications to interpret the meaning of data (i.e., encryption, compression, machine-specific conventions).
- Session — synchronisation, checkpointing, recovery of data exchange.
- Transport — process to process data transfer.
- Network — routing of datagrams from source to destination.
- Data link — data transfer between neighbouring network elements (i.e., Ethernet, WiFi).
- Physical — bits on the wire.
Sub-pages
- Application layer
- Presentation layer
- Transport layer
- Network layer
- Link layer
- Physical layer