Abstract— This paper firstly provides an overview and definition of what sub-wavelength optical networks are, by introducing the concept of shared wavelengths. A qualitative description is then given on what the value of such a network is, particularly in terms of network simplification. Like any other network approach, sub-wavelength optical networks will have application sweet spots. The remainder of the paper discusses a variety of applications and summarises the type of applications that subwavelength optical networks are most suitable for. Finally, it is proposed that these type of networks could become mainstream in the future given the ongoing conversion of traditional carrier networks into large computer networks that form database and data warehouse structures normally seen inside a data centre. These will be used for digital media content and next generation cloud applications.