Performance Analysis of Secured Efficient Distributed Storage in Cloud (SecDcloud) Encryption Algorithm Based on Avalanche Effect

The avalanche effect is a fundamental property used to measure the cryptographic strength of an encryption algorithm: any single-bit change in the plaintext or encryption key should cause approximately half of the bits in the resulting cipher text to flip unpredictably. An algorithm is considered cryptographically strong only when its avalanche effect exceeds 50%; values below this threshold signal weak diffusion and leave the cipher vulnerable to brute-force, statistical, and other cryptanalytic attacks. Evaluating the avalanche effect of a cloud encryption algorithm is therefore essential, since cloud data is typically stored on servers controlled by third-party providers, making the diffusion strength of the encryption algorithm the primary safeguard for data confidentiality and integrity. This paper determines the avalanche effect of the Secured Efficient Distributed Storage in Cloud (SecDcloud) encryption algorithm. SecDcloud is a formal-methods-based improvement on the Security Aware Efficient Distributed Storage (SA-EDS) algorithm; it partitions user data into four units using sequence head-and-last operations, pairs and encrypts them with a hash-and-salt-generated key via XOR, and distributes the cipher text across separate cloud servers. The results show avalanche effect values consistently above 50% across all ten trials, with an overall average of 54%, confirming that SecDcloud satisfies the avalanche criterion and provides the diffusion strength required of a secure cloud encryption scheme.