Network Networking-Basics Network-Structure
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OSI(Open Systems Inter-connection) model
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A standard way of how two and more computers communicate with each other. Layers:
- application
- presentation
- session
- transportation
- network
- Data link
- Physical Thats for outgoing signal, for ingoing it starts at physical and goes up.
Application Layer
Implemented in software. The data or message is sent from the application later to the presentation layer.
Presentation Layer
Turns the message from ascii and etc formats into machine readable binary format(EBCDIC), which is sent to the session layer
Session Layer
Helps setup and manages the connections. Enables sending and receiving data and terminating the connection. and then goes to the transport layer
Transport Layer
Has its own protocols of how the data will be transferred (TCP(Transmission Control Protocol), UDP(User Datagram Protocol)). Segmentation: it turns the data that it has received into segments. Flow control: controls the amount of data being transported.(like server is sending at 40mbps but client is receiving at only 10, so it has to slow down).
Network Layer
Works for the transmission of data segments transferred from a different network than the local one. ROUTER lives over here.
Logical Addressing (handling IP Addressing), moves data packets from source to destination.
Data Link Layer
Packets(contain the IP address of both the sender and the receiver, it also has subnet masking), it also adds the Mac Address of the device and forms a FRAME. Sends the frame to the physical layer
Physical Layer
Transmits the bits from the electrical signals.