OSI Model Flashcards
What is the OSI Model and what is it used for
Conceptual Framework used to describe the functions of a networking system and how applications communicate over a framework
Troubleshooting as you can identify where the problem is as the OSI Model serves as a reference model
What is level 1 of the OSI Model and What is it responsible for?
Physical Layer and It is responsible for breaking down frames into bits which can then either be sent or recieved over via physical media
What hardware is found on level 1 of the OSI Model?
Hubs, access points and media converters
Repeaters
What is layer 2 of the OSI Model And What is it Responsible for?
Data link layer
Packages the bits received from layer 1 into frames and transmits those frames on the network
Error Detection, Error Correction, Flow Control and identifying unique network devices using Mac Addresses
What devices is found on the Level 2 layer?
Network Interface Cards (NIC) Switches and Bridges
What is Level 3 of the OSI Model and what is it responsible for?
Network and How to forward traffic/data using logical addressing (not just IP)
What Devices are found in layer 3?
Routers, ICMP, IPv4 IPv6
How does layer 3 forward data?
Layer 3 forwards data through packet switching which is dividing data into packets and then forwarding based on its IP address, Packet switching cannot store data and may take different routes
What is Layer 4 and What is it responsible for?
Transport and The basic function of the Transport layer is to accept data from the layer above, split it up into smaller units, pass these data units to the Network layer, and ensure that all the pieces arrive correctly at the other end.
Isolates the upper layers
What Devices are found in layer 4?
TCP / UDP / FIREWALLS
What is TCP and UDP and what are their differences?
Protocols that establish how to establish and maintain a network conversation
TCP is a connection based protocol in which the client speaks to server and waits for an acknowledgment before sending out data in segments and then asks for acknowledgment it has been received
UDP is a connectionless protocol and sends out datagrams with no sequencing or acknowledgment or windowing.
What is Layer 5 and What is it responsible for?
Session and Preventing the intermingling of Data and responsible for controlling sessions by setting them up, maintaining and then tearing down sessions.
What devices are found in layer 5?
H.323 and NetBIOS
What is Layer 6 and what is it responsible for?
Presentation layer and responsible for formatting the data to be exchanged and securing data with encryption
Formatting is to have compatibility eg GIF
What are layer 6 devices?
Scripting languages, standard test ASCII
