Flow Scheduling for SODALES Network. The SODALES ARN enabled access network architecture is depicted in Figure 39 and provides N wavelengths each carrying 10 Gb/s. SODALES envision the research into access network having advanced control and management plane with open-access and multi-operator functionalities The initial proposal of SODALES considers the ARN comprise of 120G switching fabric and connected to the CO using 2 wavelengths. In this model, we have the ARN consisting of a 120G=3×40G Ethernet switch chassis, where the first 40G rack has 4 output ports of 10G capacity each, connected respectively to the RBS and 3 SMEs. For these users, there is no contention or statistical multiplexing. The other two 40G racks each have 48 output ports, each offering a maximum 1 Gb/s bandwidth pipe. In Figure 39, a total of 20 Gb/s (equal to 2×λ @10 Gb/s/λ) light paths are used between the ARN and the CO. We call these two wavelengths high and low priority wavelength and denote them as λH and λL respectively. Apart from this, the XG- PON function is conventional, with an intermediate AWG wavelength-routing lightpaths to other XXXx, or even allowing dedicated wavelengths to be directly routed to a 10G ONT located at a RBS or SME business premises. In this arrangement, three scenarios are considered: All λH and λL are available for the 96 Res users. This scenario is common where ARN is located in a purely residential area, without any SME or industry requirements RBS and SME are allocated 30% (or equivalent fraction) of λL and the remaining 70% (or equivalent) is available for the 96 Res as a super link. All RBS, SME, and Res contend for the λH and λL wavelengths. The flexibility offered here means that differentiated services, varying bandwidths, and differing end-user densities can be efficiently catered for. The proposed optical wireless access network architecture is depicted in Figure 40 and we assume the following: 2 wavelengths connect the ARN and the CO; Users vary in their traffic request; A node at the ARN implements basic software define logic which feeds back statistics to the central office; Wavelengths are regarded as limited and scarce resources; Non-negligible time is required to create and release optical path from source to destination. Given the requirements described above, we can formulate a problem statement for the 2 available Lambdas connecting ARN and CO.
