7) Physical Layer:-
- It is truly hardware layer which deals with the signal strength, Transmission mode i.e full duplex or half duplex, transmission rate, transmission topology i.e Ring, star etc.
- It defines the physical and mechanical properties of transmission media.
SUMMARY
NOTE(1):- IP addresses are globally unique address where as MAC addresses are locally unique addresses.
NOTE(2):- Physical layer & Data link layer operates locally.
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