1 Introduction2 Optical physical layer security threats, vulnerabilities and attacks2.2 Active optical attacks2.2.4 Alien wavelength attacks: System vendor interoperability at the optical layer is requested by network operators to allow easy network upgrades and efficient transmission of high-capacity connections over the existing infrastructures or operators. This is achieved by alien wavelengths (AW) that denotes third party ''coloured'' optical signals, originating from transponders not under the direct control of the transmission network operator . Applications of AWs can be the upgrade of a 10 Gb/s OOK legacy system provided by vendor X with new services based on 100 Gb/s coherent technology provided by vendor Y. Another application scenario of AWs is illustrated in Fig. 8 for interconnecting sub-regions of domain A (equipped with vendor X) via domain B (equipped by vendor Y) without the need of regenerating the channel each time it enters a new domain. AWs eliminate the requirement of using native wavelengths based on the system vendor technology used in the host domain. As shown in Fig. 8, AWs enable to avoid regenerations in node B1 and A5. AW provides a lot of advantages since it reduces the processing delay, the electrical power consumption, and the sub-rack space/2.2.5 Physical infrastructure attacks: These attacks target the physical network infrastructure and can be categorised in three types :3 Network survivability to attacks4 Procedures for ensuring data protection from passive attacks4.3 Ensuring optical network authentication5 Security procedures against active attacks5.3 Preventing OA attacks and multi span out-of-band crosstalk attacks6 Optical performance monitoring methods for attack detection and localisation in the optical physical layer7 ConclusionEffect on service channelsPreconditioning actions on channelsPreventing network Attack detection architectures and localisation proceduresSecurity threats related to optical networking are becoming more significant due to exponential traffic growth and the move to cloud networking, especially driven by social media, IT outsourcing, increased mobility and the need for access ''at any time, from anywhere''. Optical networks are vulnerable to several types of attacks [1, 2], typically aim...See more on ietresearch.onlinelibrary.wiley Yokogawa Test & Measurement Corporation
Optical Fiber Communications 101: Key Concepts
The monochromator has a multi-stage optical bandpass filter structure for sharp filtering characteristics to evaluate high-performance, highly functional optical
