Optical fiber communications are essential for all types of long and short distance transmissions. The aim of the article is to analyze the previously presented risks and evaluation of the two biggest and therefore the most critical risks. The first major risk is the possibility of inserting a splitter into optical distribution network and capturing portion of the entire spectrum, ie all channels in the optical fiber. The second significant security risk is crosstalk on multiplexer in networks with wavelength division multiplexing. Based on the measurements, risks were evaluated for both point-to-point and point-to-multipoint networks.
Optical fiber communications are essential for all types of long and short distance transmissions. The aim of the article is to analyze the previously presented risks and evaluation of the two biggest and therefore the most critical risks. The first major risk is the possibility of inserting a splitter into optical distribution network and capturing portion of the entire spectrum, ie all channels in the optical fiber. The second significant security risk is crosstalk on multiplexer in networks with wavelength division multiplexing. Based on the measurements, risks were evaluated for both point-to-point and point-to-multipoint networks.
Every year increases the amount of confidential information that is transmitted in optical communication networks. To ensure safe transmission of confidential information fiber optic lines are the most suitable. It is determined that the electromagnetic field of the light wave does not go beyond the optical fiber. However, under certain circumstances, interception of optical signal on the bend of the fibers is entirely possible. Thus, for the creation of optical lines with high level of information security are necessary additional measures. To this aim, in the proposed use of masking optical linear code by increasing the numbers of units are used passive components such as optical delay lines and optical splitters. The method allow increasing the number of units of code combinations to be transferred, and thus make it impossible for an adequate interpretation of the information. The advantage of the method is that the protection device is completely passive, and therefore reliable, and can be connected directly to the input and output of optical linear tract. Moreover, these devices do not require adjustment.
Solving the problem of ensuring the information security of the fiber-optics systems requires an analysis of possible methods of unauthorized access. Improving the technology of installation and operation of the fiber-optics systems not only enhances the quality and distance of information transmission over an optical cable, but also potentially expands the range of channels for possible leakage of information transmitted through it. Improving the construct of the optical fibers, the use of such technologies as wavelength division multiplexing (WDM), necessitates a complex analysis of increasing the information capacity and security of fiber-optics systems from unauthorized access. The paper compares the security of the fiber-optics systems built on the standard single mode fiber (SSMF) and dispersion shifted fiber (DSF). It is shown that, despite of the possibility of a higher information capacity, fiber-optics systems built on DSF require more careful control to avoid unauthorized access than in the case of using standard SSMF.
In telecommunication networks and in computer grid networks, a significant ongoing research is in a technology known as wavelength division multiplexing (WDM), which is capable to transport more than 1 Tbps aggregate traffic over a single fiber. However, when massive amounts of information are transported, as in optical networks, there are three issues that stand, cost-efficient ultra-high bandwidth delivery, security of information and data, and security of the network and of the transporting link layer. In optical networks, each fiber link consists of segments, each several kilometers long. Since a single WDM channel carries traffic, there are opportunities for sophisticated eavesdroppers to tap the fiber, copy a channel, isolate a specific payload and attempt to decrypt it if the encryption key is known or it is breakable with a fast computer. Therefore, end-to-end data security should not only rely on the client's encryption method but also on securing the transmission method on the optical link. In this paper, we present a WDM link security methodology that encrypts multiple channels and with multiple keys to render channel monitoring by eavesdroppers virtually impossible. Although our paper presents the applicability of the method on a point-to-point topology, it is applicable to a multilink and edge-to-edge network path.
The secure transport of messages was the concern of many early civilizations. Since then, different methods have been developed to assure that only the sender and the addressee would be able to read a message, while it would be illegible or without significant meaning to a third party. Today, this practice continues with more fervor. Wireless, wired, and optical communication networks are able to transport unimaginable amounts of data and thus privacy of information and security of the network are of the utmost concern because a good part of the transported information may be very sensitive and/or confidential. Confidentiality of information has been particularly popularized with the explosive growth of the Internet, which has touched most people's lives. However, from the outset, the Internet was based on open network architecture with computer-based nodes and without network security, and thus was vulnerable to attackers and hackers. Wireless networks transmit in unguarded space and thus are also subject to malicious actors. Dense wavelength-division multiplexing (DWDM) optical networks transport a massive aggregate traffic that has exceeded terabits per second per single fiber; therefore, the issues of information privacy and network security are equally important. As a result, the development of unbreakable cipher keys, cipher-key distribution, identification of malicious actors, source authentication, physical-link signature identification, countermeasures, and so forth has been the major thrust of research efforts with regard to cyber-security. This article focuses on cryptography, and is the first of a series of three articles on cryptography and security in communications. Subsequent articles will cover wireless and IP network security, as well as optical network security, quantum cryptography, and quantum-key distribution processes specific to optical networks.
Quantum Key Distribution (QKD) networks are the trends toward multiple users' unconditional secure communication. Based on several passive optical devices, such as beam splitter, optical switch or wavelength divided multiplexer, various types of fiber-based QKD networks have been proposed. However, it is still hard to accurately assess these networks. To find the optimal solution, a general assessment that would not involve detailed schemes is quite necessary. In this paper, we introduce an evaluation method and analyze optical-device-based QKD networks including two rational aspects: (i) network connectivity and network bandwidth which reflect the network's flexibility and performance in theory; (ii) network cost that brings pragmatic restriction on the network construction in practice. Applying this model, we compare five typical types of optical-device-based QKD networks. The explicit results demonstrate the above networks' characteristics and some valuable conclusions.
Wavelength Division Multiplexing (WDM) is a photonic technology capable to transport over a single fiber more than a Tbit/s aggregate traffic. Currently, WDM is the only deployed method in transcontinental and transoceanic applications. In the optical network, each fiber link consists of segments, each several kilometers long, the connecting points of which are amenable to tapping. When a small amount of optical signal is extracted from a tap, when the signal is properly amplified it can be monitored by unauthorized personnel thus threatening communications and land-security. Since each WDM channel carries traffic from one customer, it is not difficult for the connoisseur to demultiplex a specific channel, isolate a specific payload and break the encrypted datagram. Therefore, in addition to data encryption, high-speed communications security should also rely on securing the optical links. In this paper, we present a WDM link security method that, even if fiber is tapped, constitutes channel monitoring and information decrypting by an eavesdropper or unauthorized personnel virtually impossible. In addition, we describe the circuit building blocks behind the method that makes eavesdropping impossible.