LPsec: a fast and secure cryptographic system for optical connections

Abstract

The high capacity and low latency of optical connections are ideal for supporting the current and future communication services, including 5G and beyond. Although some of those services are already secured at the packet layer using standard stream ciphers, like Advanced Encryption Standard (AES) and ChaCha, secure transmission at the optical layer is still not implemented. To secure the optical layer, cryptographic methods need to be fast enough to support high-speed optical transmission and cannot introduce significant delay. Moreover, methods for key exchange, key generation and key expansion are required, which can be implemented on standard coherent transponders. In this paper, we propose Light Path SECurity (LPsec), a secure cryptographic solution for optical connections that involves fast data encryption using stream ciphers and key exchange using Diffie-Hellman (DH) protocol through the optical channel. To support encryption of high-speed data streams, a fast, general purpose Pseudo-Random Number Generator (PRNG) is used. Moreover, to make the scheme more secure against exhaustive search attacks, an additional substitution cipher is proposed. In contrast to the limited encryption speeds that standard stream ciphers can support, LPsec can support high-speed rates. Numerical simulation for 16-QAM, 32-QAM and 64-QAM show that LPsec provides sufficient security level while introducing negligible delay only.

Investigating Imperfect Cloning for Extending Quantum Communication Capabilities

“…Technology is developing rapidly, and soon quantum computers will exchange quantum messages among themselves, enabling distributed quantum computing. Such quantum computers, connected by the quantum Internet, can be used for various applications ranging from quantum key distribution (QKD) [ 1 ] to specialized quantum computing tasks [ 2 ], while guaranteeing information-theoretic security governed by the laws of quantum mechanics, i.e., perfect security as compared to classical approaches [ 3 ]. However, there is a fundamental barrier to the development of distributed quantum computing: the no-cloning theorem [ 4 ], which makes perfect quantum bit (qubit)—the fundamental unit of quantum information—duplication impossible.…”

DSP-Based Physical Layer Security for Coherent Optical Communication Systems

“…Many physically secure structures based on chaotic systems have also been proposed and investigated [19]- [23]. [19] provides a method to apply chaotic optical carriers into a system to achieve signal encryption, however, an eavesdropper may simply use a direct detection-based receiver and a filter with a suitable cut-off frequency to recover the data.…”

“…Furthermore the basic technique for physical layer security in [21] is investigated in intensity modulation and direct detection (IMDD) transmission systems only, thus the suitability of the security technique to coherent systems is also an important factor to consider as coherent optical systems are employed for high speed, long-reach optical communications where security is also vital. A technique for physical layer security in coherent optical systems is proposed in [23], however this technique has the major disadvantage that it cannot be retrofitted to existing coherent transmission systems, because the secure system is realized by introducing a cipher-based algorithm at the bit level.…”

Techniques for efficient and secure optical networks

“…Chapter 4 focuses on goal G.1 and covers physical layer cryptography. This chapter is based on the journal publication [JOCN22].…”

“…The technology is developing rapidly, and soon quantum computers will exchange quantum messages among themselves, enabling distributed quantum computing. Such quantum computers, connected by quantum Internet, can be used for various applications ranging from quantum key distribution (QKD) [Ah22] to specialized quantum computing tasks [WeS18], while guaranteeing information-theoretic security governed by the laws of quantum mechanics, i.e., perfect security as compared to classical approaches [JOCN22]. However, there is a fundamental barrier: the no-cloning theorem [Wo82], which makes perfect duplication of a quantum bit (qubit) -the fundamental unit of quantum information-impossible.…”