OSI

Question 1

Layer 1

Answer 1

Physical

Question 2

Layer 1 - Asynchronous communication

Answer 2

Uses start and stop bits to indicate when transmissions occur from sender to receiver
-references their own internal clocks

Question 3

Layer 1 - Synchronous communication

Answer 3

Uses reference clock to coordinate the transmissions by both sender and receiver
-network devices agree on clocking method

Question 4

1 - Broadband

Answer 4

Divided bandwidth into separate channels
- Cable TV
-FDM

Question 5

1 - Baseband

Answer 5

Uses all frequencies available and uses reference clock to coordinate transmission
- Ethernet

Question 6

Isochronous communication

Answer 6

Network devices use common reference clock source and create time slots for transmission
-less overhead than synchronous and asynchronous

Question 7

1 - TDM (Time-Division Multiplexing)

Answer 7

Easy sessions takes turns using time slots

Question 8

1 - StatTDM (Statistical Time-Division Multiplexing)

Answer 8

More efficient version of TDM
-dynamically allocates time slots on as-needed basis instead of statically assigning

Question 9

1- FDM (Frequency-Division Multiplexing)

Answer 9

Medium divided into various channels based on frequencies and each session is transmitted over a different channel
-Broadband

Question 10

3 - Packet/circuit/message switching

Answer 10

How should data be routed/forwarded:
Packet - data divided into packets

Circuit - dedicated communication link established between 2 devices

Message - data divided into messages, similar to packet, except these may be stored then forwarded.