Data Link Layer

Network Layer

Transport layer

Application Layer

Go Back N ARQ rejects out-of-order packets

In Selective Repeat ARQ, out-of-order delivery can not happen

In Go Back N ARQ , number of retransmissions in case of packet drop is 1

In Stop and Wait ARQ, lost data problem is resolved by sequence number

23

24

25

26

<=receiver rate

maximum (network rate, receiver rate)

<=network rate

minimum(network rate, receiver rate)

RTT

250 ms

2*RTT

500 ms

Increases linearly

had a constant value

Increases exponentially

shows no change

Time wait timer

Keep alive timer

Retransmission timer

Persistent timer

solve silly window syndrome problem

handle out of order data problem

calculate dynamic time out timer

calculate static time

IP

ICMP

MQTT

NTP

2^16

2^8

2^24

2^32

62 subnets and 262142 hosts.

62 subnets and 1022 hosts.

64 subnets and 262142 hosts.

64 subnets and 1024 hosts.

514 subnets and 128 hosts per subnet

514 subnets and 126 hosts per subnet

512 subnets and 126 hosts per subnet

512 subnets and 128 hosts per subnet

255.255.255.0

255.255.255.128

255.255.255.192

255.255.255.224

AE82::1:800:23E7:F5DB

DE62:6A42:1:5AC::800:23E7:F5DB

FC80:2:7:1:800:23E7:A:F5DB

AEC6::1:600::23E7:F5DB

Transmission delay: 0.5sec, propagation delay: 1.51509sec

Transmission delay: 10.48576sec, propagation delay: 0.5sec

Transmission delay: 4sec, propagation delay: 1.31072

Transmission delay: 1.31072sec, propagation delay: 4sec

It is the agreement to maintain constant bitrate.

It is the agreement to maintain a reliable connection between two hosts.

It is the agreement to maintain QoS.

It is the agreement to maintain connectivity.

Denial of service

Buffer overflows

Backdoors

Snooping

Sampling, Encoding,Quantizing,

Sampling, Quantizing, Encoding

Quantizing,Sampling, Encoding

Quantizing, Encoding, Sampling

Provides different frequency bands to different data streams.

Provides different frequency bands to different data streams.

Provides different time slots to different transmitters.

Provides same frequency bands to different data streams.

The property of instantaneous decoding is a requirement for unique decodability.

The property of instantaneous decoding is same as unique decoding.

The property of instantaneous decoding is not a requirement for unique decodability.

A code in which no code word is a prefix to another codeword is not called a prefix code.

A code in which no code word is a prefix to another codeword is called a prefix code.

A code in which a code word is a prefix to another codeword is called a prefix code.

For a codeword to be uniquely decodable, the codeword lengths do not require to satisfy any inequality.

If a codeword is not uniquely decodable, the codeword lengths satisfy the Kraft-McMillan inequality.

If a codeword is uniquely decodable, the codeword lengths satisfy the Kraft-McMillan inequality.

In Huffman procedure, symbols that appear more frequently, will have shorter codewords.

In Huffman procedure, there are no relationships between symbols frequency of occurrence and codeword lengths.

In Huffman procedure, symbols that appear less frequently, will have shorter codewords.

The necessary condition for an optimal variable-length binary code is that, in the tree corresponding to the optimal code there must be tone branches stemming from each intermediate node.

The necessary condition for an optimal variable-length binary code is that, in the tree corresponding to the optimal code there must be two branches stemming from each intermediate node.

The necessary condition for an optimal variable-length binary code is that, in the tree corresponding to the optimal code there must be three branches stemming from each intermediate node.

Adaptive Huffman coding is based on the statistics of symbols already encountered.

Adaptive Huffman coding is based on the statistics of symbols to be encountered.

Huffman coding is based on the statistics of symbols already encountered.