An Encryption and Decryption of Block Ciphers Using Multipartite Graphs A. John Kaspar, Nadar Jenita Mary Masilamani Raja, Tabitha Agnes Mangam, V. Saravanan Graph Theory in Computer Science, 2025 Cryptography is the technique that secures the process of sending and receiving messages. It involves designing the text to be communicated in a complex form, so that possible intruders might find it difficult to access the information conveyed. This approach comprises a lock that encodes or encrypts the information and a key that decodes or decrypts the ciphered text. This is essential to secure the flow of confidential information. Graph theory plays a crucial role in cryptography. A graph-based technique revolves around the maintenance of security in information flow by factoring the text into graphical models of all the cipher parameters and forming a reverse mechanism to decipher the ciphered model. In this study, we introduce a novel cryptographic graph–based model, aiming to enhance the effectiveness of the existing approaches, thereby advancing secure communication in this digital era. This approach specifically deals with block ciphers structured as a multipartite graph, ensuring a secure encryption, with symmetric key cryptography.
Unreliable Multi Server Retrial Queueing System with Reneging and Diverse Outgoing Services Saravanan Vadivel, Poongothai Venugopal, Godhandaraman Pakkirisamy Mathematical Modelling of Engineering Problems, 2024 This article explores a M/M/m unreliable retrial queue with reneging and diverse outgoing services.Incoming calls that arrive and discover all servers occupied join the orbit.The buffering incomings from the orbit retry their request after a while or leave the system without receiving service.When the orbit becomes empty, the idle server provides outgoing services.It is assumed that there are two categories of outgoing services.Due to unexpected circumstances, the server may breakdown.When a server undergoes breakdown, immediate repair process begins.Post-server breakdown, incoming calls go into orbit and retry service randomly, whereas the two variants of outgoing calls leave the system.The study utilizes a quasi-birth-death (QBD) process to analyse the stationary system size distribution.The steady state probabilities and the rate matrix are obtained through the matrix geometric method (MGM).Various performance metrics are evaluated for the proposed model.The study examines the impact of various system-based parameters on efficiency metrics with the help of numerical results.
Performance Analysis of a Retrial Queueing System with Optional Service, Unreliable Server, Balking and Feedback V. Saravanan, V. Poongothai, P. Godhandaraman International Journal of Mathematical Engineering and Management Sciences, 2023 This paper considers a Markovian retrial queueing system with an optional service, unreliable server, balking and feedback. An arriving customer can avail of immediate service if the server is free. If the potential customer encounters a busy server, it may either join the orbit or balk the system. The customers may retry their request for service from the orbit after a random amount of time. Each customer gets the First Essential Service (FES). After the completion of FES, the customers may seek the Second Optional Service (SOS) or leave the system. In the event of unforeseen circumstances, the server may encounter a breakdown, at which point an immediate repair process will be initiated. After the service completion, the customer may leave the system or re-join the orbit if not satisfied and demand regular service as feedback. In this investigation, the stationary queue size distributions are framed using a recursive approach. Various system performance measures are derived. The effects induced by the system parameters on the performance metrics are numerically and graphically analysed.
An M/M/2 Retrial Queueing System with Discouragement, Breakdowns and Repairs V. Poongothai, V. Saravanan, M. Kannan, P. Godhandaraman Aip Conference Proceedings, 2022 The current work aims to investigate the M/M/2 heterogeneous server retrial queueing system with server breakdown and repair, considering the discouragement of customers. An arriving customer will enter the service facility and check for availability of the servers. On finding either of the servers free, the customer will avail service at the available server. If both servers are busy upon arrival, then the customer will enter into the orbit or leave the system without joining the service facility. The customers awaiting service in the orbit may either retry their request for service or expecting an alarming delay in service may depart from the system without having their demands met. While serving a customer, the server may breakdown at any instant and an immediate repair process begins. Further, the customers interrupted by server breakdown stay in the service facility and resume their service once the server gets repaired. We have used the recursive method to derive the steady state queue size probability distribution. A variety of performance indices are derived from the proposed model.
RECENT SCHOLAR PUBLICATIONS
Unreliable Multi Server Retrial Queueing System with Reneging and Diverse Outgoing Services S Vadivel, P Venugopal, G Pakkirisamy Mathematical Modelling of Engineering Problems 11 (3), 571-587 , 2024 2024
Performance analysis of a multi server retrial queueing system with unreliable server, discouragement and vacation model V Saravanan, V Poongothai, P Godhandaraman Mathematics and Computers in Simulation 214, 204-226 , 2023 2023 Citations: 24
Admission control policy of a two heterogeneous server finite capacity retrial queueing system with maintenance activity V Saravanan, V Poongothai, P Godhandaraman Opsearch 60 (4), 1902-1925 , 2023 2023 Citations: 14
Performance analysis of a retrial queueing system with optional service, unreliable server, balking and feedback V Saravanan, V Poongothai, P Godhandaraman International Journal of Mathematical, Engineering and Management Sciences 8 … , 2023 2023 Citations: 10
An M / M /2 retrial queueing system with discouragement, breakdowns and repairs V Poongothai, V Saravanan, M Kannan, P Godhandaraman AIP Conference Proceedings 2516 (1), 360010 , 2022 2022 Citations: 4
AN UNRELIABLE 𝑴/𝑴/𝟏RETRIAL QUEUE WITH DISCOURAGEMENT UNDER THRESHOLD RECOVERY POLICY V POONGOTHAI, P Godhandaraman, V Saravanan Recent Advancement of Mathematics in Science and Technology, 125 , 2021 2021 Citations: 2
MOST CITED SCHOLAR PUBLICATIONS
Performance analysis of a multi server retrial queueing system with unreliable server, discouragement and vacation model V Saravanan, V Poongothai, P Godhandaraman Mathematics and Computers in Simulation 214, 204-226 , 2023 2023 Citations: 24
Admission control policy of a two heterogeneous server finite capacity retrial queueing system with maintenance activity V Saravanan, V Poongothai, P Godhandaraman Opsearch 60 (4), 1902-1925 , 2023 2023 Citations: 14
Performance analysis of a retrial queueing system with optional service, unreliable server, balking and feedback V Saravanan, V Poongothai, P Godhandaraman International Journal of Mathematical, Engineering and Management Sciences 8 … , 2023 2023 Citations: 10
An M / M /2 retrial queueing system with discouragement, breakdowns and repairs V Poongothai, V Saravanan, M Kannan, P Godhandaraman AIP Conference Proceedings 2516 (1), 360010 , 2022 2022 Citations: 4
AN UNRELIABLE 𝑴/𝑴/𝟏RETRIAL QUEUE WITH DISCOURAGEMENT UNDER THRESHOLD RECOVERY POLICY V POONGOTHAI, P Godhandaraman, V Saravanan Recent Advancement of Mathematics in Science and Technology, 125 , 2021 2021 Citations: 2
Unreliable Multi Server Retrial Queueing System with Reneging and Diverse Outgoing Services S Vadivel, P Venugopal, G Pakkirisamy Mathematical Modelling of Engineering Problems 11 (3), 571-587 , 2024 2024