# Real-time DSP Implementations of Voice Encryption Algorithms

### Cristina-Loredana Duta, Laura Gheorghe, Nicolae Tapus

#### Abstract

In the last decades, digital communications and network technologies have been growing rapidly, which makes secure speech communication an important issue. Regardless of the communication purposes, military, business or personal, people want a high level of security during their conversations. In this context, many voice encryption methods have been developed, which are based on cryptographic algorithms. One of the major issues regarding these algorithms is to identify those that can ensure high throughput when dealing with reduced bandwidth of the communication channel. A solution is to use resource constrained embedded systems because they are designed such that they consume little system resources, providing at the same time very good performances. To fulfil all the strict requirements, hardware and software optimizations should be performed by taking into consideration the complexity of the chosen algorithm, the mapping between the selected architecture and the cryptographic algorithm, the selected arithmetic unit (floating point or fixed point) and so on. The purpose of this paper is to compare and evaluate based on several criteria the Digital Signal Processor (DSP) implementations of three voice encryption algorithms in real time. The algorithms can be divided into two categories: asymmetric ciphers (NTRU and RSA) and symmetric ciphers (AES). The parameters taken into consideration for comparison between these ciphers are: encryption, decryption and delay time, complexity, packet lost and security level. All the previously mentioned algorithms were implemented on Blackfin and TMS320C6x processors. Making hardware and software level optimizations, we were able to reduce encryption/decryption/delay time, as well as to reduce the energy consumed. The purpose of this paper is to determine which is the best system hardware (DSP platform) and which encryption algorithm is feasible, safe and best suited for real-time voice encryption.

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#### Paper Citation

#### in Harvard Style

Duta C., Gheorghe L. and Tapus N. (2017). **Real-time DSP Implementations of Voice Encryption Algorithms** . In *Proceedings of the 3rd International Conference on Information Systems Security and Privacy - Volume 1: ICISSP,* ISBN 978-989-758-209-7, pages 439-446. DOI: 10.5220/0006208304390446

#### in Bibtex Style

@conference{icissp17,

author={Cristina-Loredana Duta and Laura Gheorghe and Nicolae Tapus},

title={Real-time DSP Implementations of Voice Encryption Algorithms},

booktitle={Proceedings of the 3rd International Conference on Information Systems Security and Privacy - Volume 1: ICISSP,},

year={2017},

pages={439-446},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0006208304390446},

isbn={978-989-758-209-7},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 3rd International Conference on Information Systems Security and Privacy - Volume 1: ICISSP,

TI - Real-time DSP Implementations of Voice Encryption Algorithms

SN - 978-989-758-209-7

AU - Duta C.

AU - Gheorghe L.

AU - Tapus N.

PY - 2017

SP - 439

EP - 446

DO - 10.5220/0006208304390446