Schneider Electric XPSMF2DO801 manual Following table describes the seven OSI layers bottom-top

				Equipment Description
		The following table describes the seven OSI layers (bottom-top):
Number	Layer		Data	Description
Media Layers
1	Physical layer		Bits	Defines all electrical and physical specifications for the
	Media, Signal, and Binary			devices.
	Transmission
2	Data link layer		Frames	Provides the functional and procedural means to transfer
	MAC and LLC			data between network entities and detect and correct
				errors that may occur in the Physical layer.
3	Network layer		Packets	Provides the functional and procedural means of
	Path Determination and IP			transferring variable length data sequences from a
				source to a destination via one or more networks.
Host Layers
4	Transport layer		Segments	Provides transparent transfer of data between end users.
	End-to-End Connections and
	Reliability
5	Session layer		Data	Provides the mechanism for managing the dialog
	Interhost Communication			between end-user application processes.
6	Presentation layer		Data	Relieves the Application layer of concern regarding
	Data Representation and			syntactical differences in data representation within the
	Encryption			end-user systems.
7	Application layer		Data	Interfaces directly to and performs common application
	Network Process to			services for the application processes.
	Application

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