This paper demonstrates an efficient programmable Cellular Automata (CA) based hybrid encryption technique (PCHET) for chatting applications involving multiple clients who can chat simultaneously with each other. The proposed scheme is a symmetric key encryption technique, still very lightweight and it is easy to implement. The base of the work lies in the attributes of various CA rules and their cryptographic properties. These principles rely upon the state data of its neighbors and that of its own. Further, it creates chaotic and random next state data which is extremely difficult to anticipate and its inversion is practically exorbitant in all aspects. This work is implemented in java. The evaluation outcomes of different randomness tests prescribed by National Institute of Standards and Technology (NIST) and DIEHARD test suits show that the scheme is capable of generating high degree of randomness in the ciphertext. In addition to these, a thorough comparative investigation is done with existing similar kind of ciphers such as Data Encryption Standard (DES), 3DES and Advanced Encryption Standard (AES). The execution time of the proposed work is much better than the existing scheme as it is practically required for end-to-end encryption in case of chatting applications involving multiple clients. PCHET has achieved an improvement of 1.65% in terms of execution time.

本文演示了一种高效的基于可编程元胞自动机（CA）的混合加密技术（PCHET），用于涉及多个可以同时聊天的客户端的聊天应用程序。所提出的方案是对称密钥加密技术，仍然非常轻巧并且易于实现。工作的基础在于各种CA规则的属性及其加密属性。这些原则依赖于其邻居及其自身的状态数据。此外，它创建了极其混乱和随机的下一状态数据，这是很难预测的，并且其反转实际上在所有方面都非常高。这项工作是用Java实现的。美国国家标准技术研究院（NIST）和DIEHARD测试套装规定的不同随机性测试的评估结果表明，该方案能够在密文中生成高度随机性。除此之外，还对现有的类似密码进行了全面的比较研究，例如数据加密标准（DES），3DES和高级加密标准（AES）。拟议工作的执行时间比现有方案要好得多，因为在涉及多个客户端的聊天应用程序中，端到端加密实际上是必需的。PCHET在执行时间方面实现了1.65％的改进。使用现有的类似密码，例如数据加密标准（DES），3DES和高级加密标准（AES），进行了全面的比较研究。拟议工作的执行时间比现有方案要好得多，因为在涉及多个客户端的聊天应用程序中，端到端加密实际上是必需的。PCHET在执行时间方面实现了1.65％的改进。使用现有的类似密码，例如数据加密标准（DES），3DES和高级加密标准（AES），进行了全面的比较研究。拟议工作的执行时间比现有方案要好得多，因为在涉及多个客户端的聊天应用程序中，端到端加密实际上是必需的。PCHET在执行时间方面实现了1.65％的改进。