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in many books such as [11.1], [11.2] but, as a sample, suf cient for our needs, we note that in .NET Generating USS Code 128 in .NET in many books such as [11.1], [11.2] but, as a sample, suf cient for our needs, we note that




How to generate, print barcode using .NET, Java sdk library control with example project source code free download:
chapter 11 generate, create code 128 barcode none on .net projects Web application framework 29 61. Figure 11.1. M otion control in the SZ42.

The 5 wheels at the top and the 61-wheel moved every time a letter was enciphered. The 61-wheel controlled the 37-wheel which controlled all the 5 wheels at the bottom..

in many books such as [11.1], [11.2] but, as a sample, suf cient for our needs, we note that A is 11000 B is 10011 ...

P is 01101 .net vs 2010 barcode code 128 Q is 11101 ..

. Z is 10001 (there is no obvious relationship between representations of consecutive letters of the alphabet). Although the 61- and 37-wheels determined the motion of the wheels in set C they played no direct part in the actual encipherment process, which involved only the ve binary components of the plaintext letter and the current ve pins of set A and the current ve pins of set C.

A schematic diagram of the motion control in the SZ42 is shown in Figure 11.1. The encipherment of a letter on the SZ42 was carried out as follows:.

(1) the plaint ext letter, P, was converted to its ve-bit binary equivalent in the ITA code; (2) the ve bits of P were each enciphered separately; (3) each bit of P was added (mod 2) to the value of the current pin on one of the wheels of set A, the value being 0 for an inactive pin and 1 for an active pin;. Beyond the Enigma Figure 11.2. E ncipherment process in the SZ42.

The ve streams of the plaintext letter, P, were separately added (mod 2) to the bits produced by the 2 corresponding wheels below to produce the ve streams of the cipher letter Z.. (4) the ve bi barcode code 128 for .NET ts from stage (3) were added separately (mod 2) to the value of the current pin on one of the wheels of set C, the value being 0 or 1 as at stage (3); (5) the resulting ve-bit character, Z, was converted back, via the ITA code, to give the cipher letter on a printing mechanism; (6) each wheel moved in accordance with the motion control mechanism..

The encipherme nt of each stream depended on just 2 of the 10 wheels: 1 from set A and 1 from set C. For example, the rst stream was enciphered by the 41-wheel in set A and the 43-wheel in set C, whilst the fth stream was enciphered by the 23-wheel in set A and the 59-wheel in set C. A schematic diagram of the encipherment process on the SZ42 is shown in Figure 11.

2. As only (mod 2) addition of the plaintext and keys was involved the processes of decipherment and encipherment were identical since addition and subtraction are the same (mod 2). As an illustration of the encipherment process: Example 11.

1 If the pin values on the wheels of sets A and C are Set A Set C 01011 10010. and the plaint Code 128 Code Set C for .NET ext letter is S ( 10100 in ITA) what will be the cipher letter Verify that decipherment yields the original plaintext letter..

chapter 11 Solution Plaintext letter (S) Set A pin values (mod 2) sum Set C pin values (mod 2) sum 1 0 1 1 0. 0 1 1 0 1. 1 0 1 0 1. 0 1 1 1 0. 0 1 1 0 1 P.. So the cipher visual .net barcode code 128 letter will be P. If we now start with the cipher letter, P, then, with the same pin values the decipherment process gives Cipher letter (P) Set A pin values (mod 2) sum Set C pin values (mod 2) sum.

0 0 0 1 1. 1 1 0 0 0. 1 0 1 0 1. 0 1 1 1 0. 1 1 0 0 0 S,. con rming the original plaintext letter. Breaking and setting the SZ42 Assuming that code 128 barcode for .NET the cryptanalyst knew the design details of the SZ42, as given in Figure 11.1, and that it was being used, how many possibilities would he have to consider before he could be certain of being able to decipher a message The answer is easily obtained.

The motion of the wheels and the encipherment are completely determined by the pins on the 12 wheels. Since there are 501 pins in all and each of them can be placed in either of two states, active or inactive , the number of possibilities is 2501 10151..

This is the b reaking work factor and it is so large that if every particle in the Universe was a computer and had been assigned full time ever since the Big Bang to trying all the possibilities the solution would still not have been found. Clearly, a brute force attack approach to breaking the SZ42 is hopeless. If the cryptanalyst knew all of the pin patterns and a new message appeared he would have the easier task of nding the settings of the 12 wheels at the start of the message.

The number of possibilities that he would have to try is the product of the wheel lengths, viz: 23 26 29 31 37 41 43 47 51 53 59 61.
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