Embed Size (px)
Citation preview
Interoperability
Interconnectivity
Remote connection
Logical connection
Local connection
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
The OSI ModelUser
1
2
3
4
5
6
7
Cable or other medium
The Physical Layer
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Provides electrical and mechanical
interfaces for a network.
Specifies type of medium used to connect
network devices.
Specifies how signals are transmitted on network.
The Data Link Layer
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Controls access to communication channel.
Controls the flow of data.
Organizes data into logical frames.
Identifies specific computer on the network.
Detects errors.
10010011 0000011 1010011 0010111
Data from upper layers010101010011001
The Network Layer
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Moves information to the correct address.
Assembles and disassembles packets.
Addresses and routes data packets.
Determines best path for moving data through the network.
The Transport Layer
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Takes action to correct faulty transmission.
Controls the flow of data.
Acknowledges successful receipt of data.
Fragments and reassembles data.
The Session Layer
Establishes and maintains
connection.
Manages upper layer errors.
Handles remote procedure calls.
Synchronizes communicating nodes.
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
The Presentation Layer
Encodes and decodes data.
Determines the format and structure of data.
Compresses and decompresses data.
Encrypts and decrypts.
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Adlfierwoeioriwe’
Adlfierwoeioriwe’
Alice Bob
The Application Layer
ApplicationApplication
PresentationPresentation
SessionSession
TransportTransport
NetworkNetwork
Data LinkData Link
PhysicalPhysical
Provides the user interface.
Connects the user to the network.
Provides file transfer service, email service, terminal
emulation, and other services.
A Network in ActionAlbert dictates the letter onto a tape. He
gives the tape to Penelope, who will translate it to German for him.
Penelope listens to the tape and translates it into German. Penelope gives the letter
to her assistant, Sam.
Sam puts the letter into an envelope and addresses it.
Mary gets the letter from Sam’s out box. She stuffs the letter, along with the other letters bound for
the office in Germany, into a large courier-service envelope. Mary fills out a slip on the large envelope
that will be returned by the courier in Germany to acknowledge successful delivery of the
large envelope.
Ned, the courier, brings the envelope to the local office of the courier service. He determines the best delivery
route to transfer it to its destination.
Ann, the shipping clerk, sorts through envelopes on the conveyor, ensuring that they do not get jammed up or damaged. She loads
envelopes to the correct vehicle for shipment.
The envelope is delivered to its destination.
File Transfer and the OSI Model
