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Machine learning for a 5G future
















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             Figure 5: From a manually controlled network to a cognitive autonomous network

                                                              able to add, remove or modify (e.g., split or combine) the
                                                              network configurations based on the learning of how or if the
                                                              network configurations are useful.

                                                              It is obvious that without the specialized DApps, the CE is
                                                              the default automation engine.  The critical aspect of the
                                                              design is that the system does not have to observe all states
                                                              in order to know how to behave. Full knowledge of all states
                                                              can be achieved by extrapolation from known data, i.e., the
                                                              observations made in some states can be used to predict how
                                                              to behave in other network states.

                                                               4.  LEARNING NETWORK BEHAVIOR – A CAN
                                                                   EXAMPLE FOR MOBILITY MANAGEMENT

                                                              Let us assume a CAN and the use case of managing terminal
                                                              mobility. Using a RL DApp (e.g. like that in [10][12]), the
                                                              CAN is able to learn the optimal behavior for a mobility state
                                                              (the average  velocity observed in the cell) as the best
                                                              Hysteresis (Hys) and Time-to-Trigger (TTT) values for the
                                                              state. For the network, the state-action space is very large and
           Figure 4: CAN framework – Functions of CAN system  not all states are frequently observable (some states are very
           and related Cognitive Functions                    rare) yet the CAN needs to know how to behave in all states.
                                                              We show here that CANs can effectively learn the network
                                                              response in the unknown states based on their observations
           The CME is the controller for the entire cognitive system
           instance. First it decides if a DApp configuration   in the known states. The CAN is particularized as supervised
           recommendation should be enforced on the network. In so   learning algorithms which, using multiple examples, learn to
           doing it is responsible for concurrency control  which is   perceive a data element as instance of the earlier-on learned
           different from logical coordination that is undertaken by the   network’s response to  mobility  management parameters.
           CE. The CME communicates the selected network      Then, by reasoning over the DE’s relationship  with the
           configurations to the DAPPs and the CE (for their learning   earlier examples, the algorithms can predict the likely
           and coordination purposes) through interface f. Secondly, it   network’s response to that instance.
           also defines and refines the legal/acceptable candidate
           network configurations for the different contexts of the   4.1.  Simulation set up
           different DApps based on the meta learning from the CE. In
           the simplest form, the CME masks a subset of the possible   For this study,  we obtained  data from  simulations  for 6
           network configurations as being  unnecessary (or   velocity  states [3,10,30,60,90,120 in kmph] and different
           unreachable) within a specific abstract state. So, the set of   mobility configurations (Hys and TTT) in an LTE network
           possible network configurations is fixed and the CF/DApp   of 21 states using a simulator described in  [10][12]. For each
           only selects from within this fixed set when in the specific   configuration, we simulate 200 minutes of network operation
           abstract state. A more cognitive CME may, however, also be   and note the rates of handover (HO) successes, Ping-Pongs,





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