Suppose that a disk unit has the following parameter: block size B = 1200 bytes Consider a STUDENT file with the following fields: NUMBER, 10 bytes; • LASTNAME, 20 bytes; FIRSTNAME, 20 bytes; BIRTHDATE, 10 bytes; The STUDENT file has r=10000 STUDENT records, fixed-length format, and unspanned blocking. Calculate the following values for the STUDENT file: (a) Calculate the record size R (b) Calculate the blocking factor bfr (c) Calculate the number of disk blocks b

Suppose that a disk unit has the following parameter: block size B = 1200 bytes Consider a STUDENT file with the following fields: NUMBER, 10 bytes; • LASTNAME, 20 bytes; FIRSTNAME, 20 bytes; BIRTHDATE, 10 bytes; The STUDENT file has r=10000 STUDENT records, fixed-length format, and unspanned blocking. Calculate the following values for the STUDENT file: (a) Calculate the record size R (b) Calculate the blocking factor bfr (c) Calculate the number of disk blocks b

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.10: Exponential Queues In Series And Open Queuing Networks

Problem 10P

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A file has r=30,000 EMPLOYEE records of fixed-length. Consider a disk with block size B=512 bytes. A block pointer is P=6 bytes long and a record pointer is P R =7 bytes long. Each record has the following fields: NAME (30 bytes), SSN (9 bytes), DEPARTMENTCODE (9 bytes), ADDRESS (40 bytes), PHONE (9 bytes), BIRTHDATE (8 bytes), SEX (1 byte), JOBCODE (4 bytes), SALARY (4 bytes, real number). An additional byte is used as a deletion marker. a) Calculate the record size R in bytes. b) Calculate the blocking factor bfr and the number of file blocks b assuming an unspanned organization. c) Suppose the file is ordered by the key field SSN and we want to construct a primary index on SSN. Calculate the index blocking factor bfr i.
Read question properly and give correct answer fastttt within 30 minutes.... will upvote Answer the questions below using the following information: Consider a disk with block size B = 512 bytes. A block pointer is P = 6 bytes long, and a record pointer is PR = 7 bytes long. A file has r = 30,000 EMPLOYEE records of fixed length. Each record hs the following fields: Name (30 bytes), SSN (9 bytes), Department_code (9 bytes), Address (40 bytes), Phone (9 bytes), Birth_date (8 bytes), Sex (1 byte), Job_code (4 bytes), Salary (4 bytes, real number). An additional byte is used as a deletion marker. Suppose that the file is not ordered by the key field SSN and we want to construct a B+-tree access structure (index) on SSN. Calculate: The orders p and pleaf of the B+-treeThe number of leaf-level blocks needed if blocks are approximately 69 percent full (rounded up for convenience)The number of levels needed if internal nodes are also 69 percent full (also rounded up)The total number of blocks…
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PART 2: you will try to use "brute force" to decrypt an encrypted message, where you only have the first 96-bits of the 128-bit secret key (last 4 bytes of the secret key are missing!) The program should be called "findk", and should deal with two files that contain the encrypted text as a stream of bytes and the first 96-bits of the key, respectively. The program should print out on standard output the missing 4 bytes of the key in hexadecimal, the decrypted message and the time it took to find the correct key.o To test this part, here is the encrypted file (ciphertext2.dat), and the first 96-bits of the key (partial-key.dat) Hint: the original message starts with the word "Salam". partial key is b'\x01{:\xec<\x8e\xfc\x8b\x19\xf8#\xc0' ciphertext2 is…
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With linked allocation, each file is a linked list of disk blocks; the disk blocks may be scattered anywhereon the disk. The directory contains a pointer to the first and last blocks of the file. Each block contains a pointerto the next block. Refer to the illustration below. Need help to fill in the codes in void main() --- #include<stdio.h>#include<stdlib.h>#define TOTAL_DISK_BLOCKS 32#define TOTAL_DISK_INODES 8int blockStatus[TOTAL_DISK_BLOCKS]; // free = 0int blockList[TOTAL_DISK_BLOCKS - TOTAL_DISK_INODES]; // list of blocks of a filestruct file_table {char fileName[20];int fileSize;struct block *sb;};struct file_table fileTable[TOTAL_DISK_BLOCKS - TOTAL_DISK_INODES];struct block {int blockNumber;struct block *next;};int AllocateBlocks(int Size) {---}void main(){int i = 0, j = 0, numFiles = 0, nextBlock= 0, ret = 1;char s[20]; struct block *temp;---for(i = 0; i < numFiles; i++) {---ret = AllocateBlocks(fileTable[i].fileSize);---}---//Seed the pseudo-random number…
Experimenting with AES-128 symmetric key cipher.using python please. PART 2: you will try to use "brute force" to decrypt an encrypted message, where you only have the first 96-bits of the 128-bit secret key (last 4 bytes of the secret key are missing!) The program should be called "findk", and should deal with two files that contain the encrypted text as a stream of bytes and the first 96-bits of the key, respectively. The program should print out on standard output the missing 4 bytes of the key in hexadecimal, the decrypted message and the time it took to find the correct key.o To test this part, here is the encrypted file (ciphertext2.dat), and the first 96-bits of the key (partial-key.dat) Hint: the original message starts with the word "Salam". partial key is b'\x01{:\xec<\x8e\xfc\x8b\x19\xf8#\xc0' ciphertext2 is…
Question #9 Is each of the following an absolute pathname, a relative pathname, or a simple filename? milk_co correspond/business/milk_co /home/max /home/max/literature/promo .. letter.0210 Question #10 Suppose you have a file that is linked to a file owned by another user. How can you ensure that changes to the file are no longer shared? Question #11 If /home/zach/draft and /home/max/letter are links to the same file and the following sequence of events occurs, what will be the date in the opening of the letter? Max gives the command vim letter. Zach gives the command vim draft. Zach changes the date in the opening of the letter to January 31, writes the file, and exits from vim. Max changes the date to February 1, writes the file, and exits from vim. Question #12 What is an inode? What happens to the inode when you move a file within a filesystem? Question #13 The ls –i command displays a filename…
Assume that each block has B = 1000 Bytes, and the buffer pool has m = 1001 frames. What is theexact size of the largest file external memory sorting can sort within 3 passes, i.e., pass 0 to pass 2with pass 2 producing only 1 run?
Experimenting with AES-128 symmetric key cipher.using python PART 2: you will try to use "brute force" to decrypt an encrypted message, where you only have the first 96-bits of the 128-bit secret key (last 4 bytes of the secret key are missing!) The program should be called "findk", and should deal with two files that contain the encrypted text as a stream of bytes and the first 96-bits of the key, respectively. The program should print out on standard output the missing 4 bytes of the key in hexadecimal, the decrypted message and the time it took to find the correct key.o To test this part, here is the encrypted file (ciphertext2.dat), and the first 96-bits of the key (partial-key.dat) Hint: the original message starts with the word "Salam". Answer you provided .from Crypto.Cipher import AESdef revpad(s):"""This function is to remove padding.parameters:s:strstring to be reverse padded"""k = ord(s[-1])temp = 0 # temporary variable to check paddingfor i in range(1, k): # for loop to…
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