Optical fibers are becoming commonly used beside data transmissions for dissemination of ultra-precise and stable quantities or alternatively as distributed sensors of for example acoustic and mechanic vibrations, seismic waves, temperature etc. There have been developed methods for these transfers and their stabilization, allowing thus to achieve excellent performances. Such performance is bound with utilization of single physical medium for both ways of propagation. These methods are attractive both for very high-performance applications and as a secure alternative complementary to radio and satellite-based transfer methods. From economical point of view, sharing fibers with regular data traffic is an advantage, especially for longer distances and large infrastructures. Unfortunately, the most often used wavelengths are located almost in the middle of telecommunication band. Due to continuous data traffic growth and utilization of flexible spectral allocation, the collision in wavelength plan will occur more and more often. In this paper we overview alternative wavelengths suitable for these transfers, we also propose suitable methods for all-optical reach extension, by all-optical amplification. Shared line design allowing transfer of ultra-stable quantities in three different spectral bands is proposed and such design is evaluated.
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