網絡：練習題

Which network component is primarily responsible for connecting different networks, such as a Local Area Network (LAN) to the Internet, and forwarding data packets based on their Internet Protocol (IP) addresses?

Which of the following statements correctly identifies a feature of Internet Protocol version 6 (IPv6) addresses?

A network engineer needs to calculate the theoretical transmission time for an uncompressed image file over a dedicated network connection.

The image has dimensions of \(2048 \times 1536\) pixels with a colour depth of \(24\) bits per pixel (bpp).
The network connection has a constant bandwidth of \(100\text{ Mbps}\) (where \(1\text{ Mbps} = 10^6\text{ bits per second}\)).

Which of the following gives the exact theoretical transmission time for this image file?

A large organization is designing a wide-area network (WAN) that requires high-speed data transmission over long distances with minimal electromagnetic interference and high security. The transmission media must connect two offices located 50 kilometers apart. Based on the network transmission media characteristics, which option is the most appropriate?

Compare the address space capacity of Internet Protocol version 4 (IPv4) and version 6 (IPv6) in terms of bits.

An organization is deciding between copper twisted pair and fibre optic cables for a new high-speed backbone connection.
Evaluate why fibre optic is preferred over copper for long-distance transmissions and environments with high electromagnetic interference.

During a Voice Over Internet Protocol (VOIP) call, a user experiences intermittent audio gaps and delays.
Identify the network metric responsible for the variation in the delay of received packets and explain how it affects the quality of the real-time stream.

An international logistics company uses various network metrics and components to ensure efficient data transmission between its regional warehouses.

(a) Define the term latency and explain how high latency could negatively impact a real-time tracking system. (3 points)
(b) The company uses routers and gateways. Explain the specific role of a gateway when the internal network needs to communicate with an external system using a different protocol suite. (2 points)

A media enterprise operates a high-bandwidth distributed network across multiple regional hubs. Video files are transmitted across dedicated high-speed links, while voice-over-IP (VOIP) conferencing and database operations run continuously across the network.

(a) A raw uncompressed video file with a size of \(45\text{ GiB}\) needs to be transferred from a studio to a central data store over a network connection with an effective bandwidth of \(120\text{ Mbps}\). Calculate the theoretical minimum transmission time in seconds required to complete the transfer. Show all intermediate calculation steps, converting the file size to bits using standard IEC binary prefix definitions. (4 points)

(b) During peak hours, staff report significant quality degradation during VOIP calls, including stuttering audio and out-of-order words, even though the total bandwidth usage is well below capacity.
(i) State the specific network metric that causes this issue and explain how it affects VOIP communication. (2 points)
(ii) Explain the operational function of a network switch at the Data Link Layer (Layer 2) of the OSI model and describe how it prevents network congestion compared to a hub. (2 points)