Question

In: Advanced Math

In practice, an LFSR sequence would not be used as keystream for a stream cipher, due...

In practice, an LFSR sequence would not be used as keystream for a stream cipher, due to the linear complexity. Answer the following questions about linear complexity.

What is the linear complexity of a maximal length LFSR output sequence?
Describe one method using LFSRs to produce a binary output sequence but with increased linear complexity. Draw a diagram to illustrate your construction.

Expert Solution

a.

Linear complexity is also called linear span.If an LFSR sequence of n stages has the maximal period ,then it is called a maximal length sequence,shortened as m - sequence.

b.

One standed wa is as follows.Let, n primitive LFSR with lengths with ,

now we take the GCD

and take a nonlinear boolean function

with

for that we have a output of linear complexity

evaluted over the integers, where output of LFSR is input as the variable of the bolean function.this is called the combination generator,

example.

Colby Messinger answered 1 year ago

List the primitive operations used in the RC4 stream cipher algorithm for A) Key Stream Generation...

List the primitive operations used in the RC4 stream cipher algorithm for A) Key Stream Generation B) Bit Stream Encryption

Stream Cipher. A message is encoded by exclusive-or’ing each bit with a random bit stream. (In...

Stream Cipher. A message is encoded by exclusive-or’ing each bit with a random bit stream. (In exclusive or, 0⊕0 = 0, 1⊕0 = 1, 0⊕1 = 1, and 1⊕1 = 0.) a. Recover the original message from the random stream and encrypted stream, by filling in the blanks in the “Recovered” and “ASCII” rows. (In the ASCII column, interpret the byte as an ASCII character and write the value in that row.) Message: ? ? ? ? ? ? ?...

Problem 1. Write two computer programs to simulate a Unicode stream cipher that consists of both...

Problem 1. Write two computer programs to simulate a Unicode stream cipher that consists of both encryption and decryption algorithms. The encryption program accepts inputs from an existing text file, called “letter.txt.” The encryption program produces an output ciphertext file, called “secret” The decryption program takes “secret” as input and decrypts it into a plaintext, called “message.txt.” - The random “seed” must be known, but be kept secure, by the pseudorandom number generators in both encryption and decryption programs. Note...

A sequence detector is monitoring a serial input stream looking for either 0101 or 0110. The...

A sequence detector is monitoring a serial input stream looking for either 0101 or 0110. The output is two consecutive cycles of 1’s, with the first of the two being asserted in the same cycle as the last input matching the sequence; in other words, it has to be a Mealy machine. Draw the state diagram for this sequence detector Assign states and create the state table, showing next states and output as a function of current state and input....

If a Vigenere cipher uses the keyword CATS, what is the key used and what is...

If a Vigenere cipher uses the keyword CATS, what is the key used and what is the ciphertext that corresponds to the plaintext CATSCANS

Think about a bacterial cell entered the blood stream of a human. State the probable sequence...

Think about a bacterial cell entered the blood stream of a human. State the probable sequence of immunological interactions and responses that will occur in both innate and adaptive immune system and support your answer with molecules, receptors, pathways and cells involved. (200-300 words)

Write sequence of the DNA strand that would be complementary to the DNA sequence shown below....

Write sequence of the DNA strand that would be complementary to the DNA sequence shown below. Label the 3' and 5' ends ofthe new strand. 3' T A C C G A T G G 5'

Julius Caesar used one of the earliest known cipher systems to communicate with Cicero in Rome...

Julius Caesar used one of the earliest known cipher systems to communicate with Cicero in Rome while he was conquering Europe. Caesar knew that there was a very high risk of ambush or spies when sending messages; therefore, he developed a cryptographic system now known as the Caesar cipher. Primary Task Response: Please provide a detailed response to the below to include specific details and examples. What is the Caesar ROT3 Cipher? How does it work? Although the Caesar cipher...

A small village is located near a stream which is to be used as the source...

A small village is located near a stream which is to be used as the source of water supply for the community. The minimum flow in the stream is 550 m3/h. The population analysis reveals that the population is expected to increase linearly from a population of 10,000 in 2008 to 30,000 in 2058. The water consumption of the community is estimated to reach an annual average demand of 300 L/capita/day, a maximum daily demand of 1.8 times the annual...

A)A sequence of quarterly payments o P6,267 each, with the first payment due at the end...

A)A sequence of quarterly payments o P6,267 each, with the first payment due at the end of 2 years and the last payment at the end of 13 years. Find the present worth of these payments if money is worth 5% compounded quarterly. B)A manufacture borrows P2,211,340 with interest at 6% compounded monthly, and agrees to discharge the loan by a sequence of equal monthly payments for 4 years with the first payment at the beginning of the 4th year. Find...