Mathematical model analysis of password combination security of letter lock

This paper aims to explore the security of letter-lock password, and evaluate its strength by building a mathematical model. Firstly, we introduce the basic concept and working principle of letter lock, then establish a mathematical model based on the knowledge of probability theory and combinatorial mathematics, and then calculate the password security index under different conditions. Finally, combined with practical application scenarios, some suggestions are put forward to improve password security.

I. Introduction

In daily life, in order to protect personal privacy or important items from being touched by others, people often use various locks with password function, among which the most common one is letter lock (also known as word lock). Compared with digital passwords, it is novel and interesting to use English letters as unlocking codes. At the same time, in some specific situations (such as school dormitory access control system), the use of English characters can also reduce the difficulty of memory and facilitate the user's operation. However, due to the limited number of English letters and relatively simple arrangement and combination, this undoubtedly brings security risks to this kind of locks-that is, they are vulnerable to violent cracking attacks.

Second, the basic introduction and working principle of letter lock

1. Basic composition: Usually, a standard letter lock consists of several turntables, each of which is engraved with 26 lowercase letters A ~ Z..

2. Opening rules: users need to turn each turntable to the correct position in order to unlock it successfully. (Note: It is assumed that all legal passwords are composed of lowercase letters.)

3. Working principle: When the user inputs the correct sequence, the internal mechanical structure will be activated and the unlocking action will be triggered; Otherwise, it cannot be opened.

Third, mathematical modeling and analysis

In order to solve the above-mentioned problems, we need to make detailed statistics and summary of all possible situations in the letter lock, and establish a suitable mathematical model on this basis for subsequent research.

(1) Estimated total number of combinations:

Assuming that there are n independently rotating turntables, and there are m choices on each turntable (here, the value is 26), then the total number of alternatives, N = m1wertn, can better describe the changing trend of the security level of the letter lock password, and accordingly, some concrete suggestions for improvement are given. At the same time, it is worth noting that although this paper only discusses it from the theoretical level, more factors should be considered in the practical application process.

标签：

本文地址：https://tepinji.com/Smas/2731.html