WorksheetsCN Theory Quiz
Total questions: 11
Worksheet time: 7mins
Which of the following statements is TRUE about the OSI and TCP/IP reference models?
The OSI model has 5 layers, while the TCP/IP model has 7 layers.
The TCP/IP model combines the session and presentation layers into the application layer.
The OSI model defines protocols, but TCP/IP defines only architecture.
The data link layer in OSI corresponds to the physical layer in TCP/IP.
A message of 12,000 bits is to be sent from host A to host B over a path of 3 links using packet switching.
Each link has a bandwidth of 1 Mbps, and the propagation delay per link is 10 ms.
The message is divided into 6 packets of 2000 bits each. Ignore queuing and processing delays.
Assume store-and-forward packet switching.
Find the total end-to-end delay.
(a)
In a __________ topology, failure of a single link affects only the two directly connected devices,
whereas in a __________ topology, failure of a single node can bring down the entire network.
(a)
Which of the following statements is TRUE about network application architectures?
Hybrid models are only used for small-scale applications.
In a client-server model, each node has equal responsibilities and resources.
Peer-to-peer systems cannot use client-server components.
In a peer-to-peer model, scalability improves but reliability decreases due to lack of centralized control.
A client requests an HTML file that references 5 images from the same server.
Each object (HTML + 5 images) is 10 KB in size, link bandwidth = 100 kbps, and RTT = 100 ms.
Assume non-persistent HTTP (one TCP connection per object) with no parallel connections.
Ignore TCP slow start and transmission delay except for data transfer.
Find the total response time approximately.
(a)
The protocol used to send mail from a client to a mail server is __________.
The protocol used to retrieve mail and keep copies on the server is __________.
The format that allows sending multimedia data such as audio or images in e-mails is __________.
(a)
A sender uses Go-Back-N ARQ over a link with:
Bit rate = 1 Mbps
One-way propagation delay = 50 ms
Frame size = 1000 bytes
Window size = 10 frames
Find the maximum efficiency of the link.
(a)
A TCP sender starts transmission with slow start.
Initial threshold = 16 segments.
Each RTT, congestion window (CWND) doubles until threshold, then increases linearly.
Find the CWND growth (in segments) over each RTT if no packet loss occurs for first 8 RTTs.
(a)
The protocol used to map an IP address to a MAC address is __________.
The protocol used by a host to obtain an IP address automatically is __________.
The control message used by routers to report unreachable networks is sent via __________.
(a)
Match the following routing algorithms with their characteristics:
Algorithm Characteristic
1. Distance Vector A. Uses Dijkstra’s shortest-path algorith
2. Link State B. Uses Bellman-Ford equation
3. Path Vector C. Used in inter-domain routing (BGP)
1-B, 2-C, 3-A
1-C, 2-B, 3-A
1-A, 2-B, 3-C
1-B, 2-A, 3-C
You are given a network 192.168.10.0/24.
You must create 5 subnets, each capable of supporting at least 30 usable hosts.
Find:
(a) The new subnet mask
(b) The first three subnet addresses
(a)
