# Computational Complexity of Modified Blowfish Cryptographic Algorithm on Video Data
###### Abstract
The information is encrypted using the Blowfish technique, and the secret message is then embedded in an audio file using the discrete wavelet transform. The authors assert that their method is efficient at hiding information in audio files such that data may be sent to their intended location without being tampered with. [PERSON], [PERSON], and [PERSON] [20] enhanced data security by modifying the Blowfish algorithm. They created a software program to encrypt files. The encryption algorithm is implemented when a file is separated into several sections based on the user's specifications. They changed the F-function in the Blowfish algorithm to improve the software's performance. The F-function is made up of four S-boxes (S1, S2, S3, and S4). F(X) = ((S1 + S2 mod 232) XOR S3 + S4 mod 232) XOR S3 + S4 mod 232). They changed F(X) = ((S1 XOR S2 mod 232) + (S3 XOR S4 mod 232) to F(X) = ((S1 XOR S2 mod 232) + (S3 XOR S4 mod 232)). They demonstrated that the modified Blowfish algorithm takes 14 percent less time to execute than the original Blowfish method in an experiment. The Blowfish technique was updated by [PERSON] and [PERSON] [21] in such a way that the larger the key lengths, the stronger the key; however, the encryption process periods are considerable. To address this issue in the proposed technique, decreasing two S-boxes will increase performance and information security. When compared to the original techniques, the primary advantage of the modified Blowfish algorithm is that the processing time is reduced to 0.2 ms and the throughput is increased to 0.24 bytes/ms. The optimized Blowfish encryption technique's cryptanalysis was explored, and the algorithm was tested with several data types such as text files, audio files, and video files. [PERSON], [PERSON], and [PERSON] [22] show the Blowfish method's effectiveness by utilizing the overall time complexity, avalanche impact, and throughput as factors in various testing situations. The Blowfish algorithm was written in VHDL and implemented on an FPGA. The results show that lowering the round of Feistel ciphers reduces the total encryption time, increases throughput, and has no major impact on the avalanche effect. [PERSON], [PERSON], [PERSON], and [PERSON] [23] proposed a novel data encryption method based on the Blowfish algorithm. They designed and implemented a new strategy based on the benefits of the Blowfish algorithm to improve the previous algorithm's performance in terms of factors such as the throughput and computational cost. The most noteworthy feature of this improved Blowfish cryptographic algorithm is that the encrypted message generated each time is unique. This is because each time it is run, a new random variable is generated, resulting in a difference in the F function's application over each round. The security element of the Blowfish method will be considerably improved as a result of the different cipher text produced for the same input. [PERSON] and [PERSON] [24] investigated IoT security issues and mechanisms. According to an analysis of various IoT security issues, the majority of them arise in the insecure passage that links distinct IoT networks, as well as IoT and WSN gateways. Cryptographic techniques can be used at the network level, where data communication protection is provided. The time complexity, memory utilization, throughput, energy usage, and privacy are all factors to consider; accordingly, Blowfish was determined to be the best cryptographic algorithm, making it suitable for IoT. [PERSON] and [PERSON] [25] suggested an enhanced Blowfish technique based on five S-boxes for picture scrambling. The Blowfish algorithm's security level was enhanced by raising the difficulty of cracking the original message, resulting in protection from unauthorized assault. This approach uses grayscale images of various sizes to implement a 64-bit block encrypted with a symmetrical variable-length key.