OSI MODEL Flashcards
LAYER 1 (3 cards)
Define the physical layer
This is where transmission of bits across the network occurs and it includes physical and electrical network characteristics
For copper wires like cat 5 or cat 6 network , there is zero voltage on the wire when you have zero bit. You might use +- 5V to represent a 1
Define transition modulation
If it changes during the clock cycle, then a 1 is represented , otherwise a 0 is represented
If we use a Cat 5 or Cat 6 cable, we may have a certain connector at the end called RJ45
There are 2 ways those connectors are wired:
1 Straight through cables
2 Crossover cables(On end TIA EIA/ 568A & the other end TIA /EIA 568B)
What is the difference between a synchronous transmission and an asynchronous transmission?
Asynchronous -> Eg You call someone, he doesn’t pick up, you leave a VM. Communication occurs out of sync or out of time. The intended receiver can always go back to the message and listen to it again. This happens through a start and stop bit.
