Related Questions8 Items
Q1.MCQ
Identify the ONE CORRECT matching between the OSI layers and their corresponding functionalities as shown.
| OSI Layers | Functionalities |
| :--- | :--- |
| (a) Network layer | (I) Packet routing |
| (b) Transport layer | (II) Framing and error handling |
| (c) Datalink layer | (III) Host to host communication |
Q2.MCQ
A packet with the destination IP address $145.36.109.70$ arrives at a router whose routing table is shown. Which interface will the packet be forwarded to?
!image(https://uadmin.udsfgecw.tech/file/download/public/public:bf99f67c-2c0f-430f-a663-be1bd74f1c7b.jpg)
Q3.NUMERICAL
Suppose a message of size $15000$ bytes is transmitted from a source to a destination using IPv4 protocol via two routers as shown in the figure. Each router has a defined maximum transmission unit (MTU) as shown in the figure, including IP header. The number of fragments that will be delivered to the destination is \\\\\\\. (Answer in integer)
!image(https://uadmin.udsfgecw.tech/file/download/public/public:cae6ae61-604a-48e6-8de3-c7ad8db9c41f.png)
Q4.M-MCQ
Consider the 3-way handshaking protocol for TCP connection establishment. Let the three packets exchanged during the connection establishment be denoted as P1, P2, and P3, in order. Which of the following option(s) is/are TRUE with respect to TCP header flags that are set in the packets?
Q5.MCQ
Consider a network path P—Q—R between nodes P and R via router Q. Node P sends a file of size $10^6$ bytes to R via this path by splitting the file into chunks of $10^3$ bytes each. Node P sends these chunks one after the other without any wait time between the successive chunk transmissions. Assume that the size of extra headers added to these chunks is negligible, and that the chunk size is less than the MTU.
Each of the links P—Q and Q—R has a bandwidth of $10^6$ bits/sec, and negligible propagation latency. Router Q immediately transmits every packet it receives from P to R, with negligible processing and queueing delays. Router Q can simultaneously receive on link P—Q and transmit on link Q—R.
Assume P starts transmitting the chunks at time $t = 0$.
Which one of the following options gives the time (in seconds, rounded off to 3 decimal places) at which R receives all the chunks of the file?
Q6.NUMERICAL
Consider the entries shown below in the forwarding table of an IP router. Each entry consists of an IP prefix and the corresponding next hop router for packets whose destination IP address matches the prefix. The notation “/N” in a prefix indicates a subnet mask with the most significant N bits set to 1.
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This router forwards $20$ packets each to $5$ hosts. The IP addresses of the hosts are $10.1.1.16$, $10.1.1.72$, $10.1.1.132$, $10.1.1.191$, and $10.1.1.205$. The number of packets forwarded via the next hop router R2 is
Q7.NUMERICAL
Consider sending an IP datagram of size $1420$ bytes (including $20$ bytes of IP header) from a sender to a receiver over a path of two links with a router between them. The first link (sender to router) has an MTU (Maximum Transmission Unit) size of $542$ bytes, while the second link (router to receiver) has an MTU size of $360$ bytes. The number of fragments that would be delivered at the receiver is
Q8.MCQ
The information bit sequence $\{1 \ 1 \ 1 \ 0 \ 1 \ 0 \ 1 \ 0 \ 1\}$ is to be transmitted by encoding with Cyclic Redundancy Check - 4 (CRC-4) code, for which the generator polynomial is $C(x) = x^4 + x + 1$. The encoded sequence of bits is .
Computer Science And EngineeringComputer Networks (CN)Multiple Choice (MCQ)1 Mark
Q5.
Consider a network path P—Q—R between nodes P and R via router Q. Node P sends a file of size 106 bytes to R via this path by splitting the file into chunks of 103 bytes each. Node P sends these chunks one after the other without any wait time between the successive chunk transmissions. Assume that the size of extra headers added to these chunks is negligible, and that the chunk size is less than the MTU.
Each of the links P—Q and Q—R has a bandwidth of 106 bits/sec, and negligible propagation latency. Router Q immediately transmits every packet it receives from P to R, with negligible processing and queueing delays. Router Q can simultaneously receive on link P—Q and transmit on link Q—R.
Assume P starts transmitting the chunks at time t=0. Which one of the following options gives the time (in seconds, rounded off to 3 decimal places) at which R receives all the chunks of the file?
A
8.000
B
8.008
C
15.992
D
16.000