standard OSI has 7 layers

ften used for data communications is the OSI (Open Systems Interconecting)

so with this application every computer with different operating systems will be able to communicate fluently and global data.
Another advantage to the vendor side of this standard will vendors promise their products will sell in the market.

standard OSI has 7 layers, seven layers has a function and responsibility of their own.
1. bottom layer is the physical layer, which is useful for
physical connection (cabling using RJ45)
2. data link layer (layer works on the side of the modem where
function to perform modulation and demodulation)
3. network layer (network layer)
4. transport layer (Serves for reliable data transfer,
responsible for the integrity of data in data transmission
data exchange in the relationship between transmitter
and receiver)
5. session layer (Serves to control the communication between
application, build, maintain and terminate sessions between
application)
6. presentation layer (Serves to overcome differences
data format, compression, and encryption of data)
7. application layer (As a user interface to the OSI environment,
examples of application layer is the e-mail, ftp and http).

example of data communication is the Internet.
with any Internet connection worldwide data exchange easier.
although different operating systems (Windows, Linux, MacOS, OS / 2, BSD) all can make data communications.
for all operating systems and devices to follow ISO standards that OSI.