Networks

Question 1

Circuit Switched Networks

Answer 1

creates a fixed path between two devices before data transfer, reserving bandwidth for the entire session

Efficient for continuous use but wasteful if idle
(e.g. PSTN phone call)

Question 2

Demultiplexing

Answer 2

routes received data to the correct application using identifiers like port numbers (e.g., a router directing packets to the appropriate application using TCP/UDP ports)

Question 3

server program

Answer 3

software application that provides services (e.g., web hosting, file storage) upon request from clients

runs continuously, waiting for client requests.

Question 4

client program

Answer 4

software that requests and uses services provided by a server (e.g., a web browser requesting a webpage from a web server)

Question 5

Processing Delay

Answer 5

Time taken by a router to examine packet headers and decide forwarding.

Question 6

Queuing Delay

Answer 6

Time spent in a router’s buffer awaiting transmission (depends on traffic load).

Question 7

Transmission Delay

Answer 7

Time to push all packet bits onto the link (depends on packet size and link bandwidth).

Question 8

Propagation Delay

Answer 8

Time for a signal to travel across a medium (depends on distance and speed).

Question 9

Packet Loss occurs

Answer 9

router’s buffer is full, discarding incoming packets (common in congestion).

Question 10

Packet switching

Answer 10

Data is broken into packets, each with a header containing control information.

Packets travel independently across the network, possibly taking different paths.

Routers forward packets based on destination addresses, reassembling them at the endpoint.

Question 11

Packet switching over circuit switching

Answer 11

Efficient bandwidth usage: no dedicated path so resources are shared dynamically

robustness: if a link fails, packets can reroute through alternative paths
(e.g. Sending an email)