Question

Assume we encrypt a one “block” message (16 bytes) with a 128 bit OTP key. How...

Assume we encrypt a one “block” message (16 bytes) with a 128 bit OTP key. How long will it take to decipher the message if we are doing 12 x 10^16 XORs per second?

Engineering   Computer-Science   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

Size of message = 16 bytes

But 1 byte = 8 bits

Size of message in bits = 16 x 8 = 128 bits

Size of key = 128 bits

In OTP, we XOR every message bit with its corresponding key bit

It is given that we are doing 12 x 10^16 XOR operations per second.

Time taken by 1 XOR operation is :

Time taken to try 1 key is :

Now in order to decipher the message we need to try every possible key

Number of possible keys = 2^128

Time taken is :

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
DES uses a 56-bit key. Let's say you encrypt a message using single DES. With a...
DES uses a 56-bit key. Let's say you encrypt a message using single DES. With a 56-bit key there are 2^56 possible different keys. On average an attacker would only need to try half this number of keys to guess the correct key and break the system. If a cryptanalyst can try 1,000,000 keys per second, how long on average would it take to discover the key and recover the plaintext?
Assume one file has r = 10^6 records. Each record takes R = 100 bytes, of...
Assume one file has r = 10^6 records. Each record takes R = 100 bytes, of which 10 bytes are for the key of the record. Suppose the key values range from 1 through 1,000,000 inclusive. Assume the block size B is 1000 bytes for all files, and that an address (block pointer, tree node pointer, or data record pointer) takes 10 bytes. What is the blocking factor bfr i for the single level index ? How many index blocks...
Assume that a source sends a message containing 8 packets to the destination and there are...
Assume that a source sends a message containing 8 packets to the destination and there are 4 routers on the path. Assume the bandwidth of each link is 200 Mbps, and the size of each packet is 16 Kb. Assume the length of each link is 20 kilometers, and the propagation speed is 2 x 108 meters per second. Assume each router begins retransmitting a packet after it has finished receiving the packet and processed it for 4 microseconds (dproc...
At 4:35 AM, a covert channel with a bandwidth of 2 bit/sec gains access to a...
At 4:35 AM, a covert channel with a bandwidth of 2 bit/sec gains access to a 2048 byte plaintext message that reads “Bomb Location X at 6:05 AM”. How long will it take to transmit the plaintext of this message? If the covert channel has no access to the encryption key used for the communication, is the scenario a computationally secure one for the transmitter?
how much water we need for one block of cement given : grade of cement M5...
how much water we need for one block of cement given : grade of cement M5 (1 x 5 x 10) volume of dry cement = 0.347 m*3 volume of one block = 980400mm*3
1. The memory units that follow are specified by the number of words times the number...
1. The memory units that follow are specified by the number of words times the number of bits per word. How many address lines and input/output data lines are needed in each case? (a) 8K X 16 (b) 2G X 8 (c) 16M X 32 (d) 256K X 64 2. Give the number of bytes stored in each memory unit in question 1. 3. Word number 563 decimal in the memory shown in Fig. 7.3 (see Mano-Ch7.pdf) contains the binary...
Use python language please #One of the early common methods for encrypting text was the #Playfair...
Use python language please #One of the early common methods for encrypting text was the #Playfair cipher. You can read more about the Playfair cipher #here: https://en.wikipedia.org/wiki/Playfair_cipher # #The Playfair cipher starts with a 5x5 matrix of letters, #such as this one: # # D A V I O # Y N E R B # C F G H K # L M P Q S # T U W X Z # #To fit the 26-letter alphabet into...
Computer archieture 1. Let us assume we have such a machine. The physical RAM has 32...
Computer archieture 1. Let us assume we have such a machine. The physical RAM has 32 bytes, and is evenly divided into 4 pages. The virtual memory has 16 pages. The content in the page table and physical RAM is shown below Physical RAM Page Num Page data 3 11 ~QWERTYU 2 10 IOPASDFG 1 01 HJKLZXCV 0 00 BNM<>[]? Page table 15 0 14 0 13 0 12 1 01 11 0 10 0 9 1 11 8 0...
2) Allowing (or requiring) users to use numerical digits (including 0) and one of 28 “special...
2) Allowing (or requiring) users to use numerical digits (including 0) and one of 28 “special characters” dramatically increases the number of possible passwords. Furthermore, passwords often are case-sensitive, effectively doubling the size of the alphabet by defining 52 distinct letter characters.    Assuming that passwords are case-sensitive and can include numerical digits and special characters, how many possible 6, 8 and 10 character passwords can be created? (8 points) 3) Allowing digits and special characters creates an enormous number...
NWS620S Tutorial 1: Symmetric Encryption - DES Encryption is the translation of data into a secret...
NWS620S Tutorial 1: Symmetric Encryption - DES Encryption is the translation of data into a secret code so that only authorised entities can read it. Encrypting data is considered a very effective way of achieving data security. To access encrypted data, you must have access to a secret key that enables you to decrypt it. Unencrypted data is called plain text; encrypted data is referred to as cipher text. There are two types of encryption: • Symmetric encryption • Asymmetric...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT