# The Challenges and Compatibility of Mobility Management Solutions for Future Networks
## 5 Recent MM Techniques and 5G Architecture
### Revealed Gaps, Prospective Solutions, and Expected Framework  
Our discussion and analysis from Sections 2-5 introduced the requirements from MM approaches, used as models for future MM systems, in order to fulfill the requirements mentioned in Tables 1 and 2. Next, we have investigated the legacy and current MM mechanisms for utilizing 5G and next-generation networks in Tables 3 and 4. Nevertheless, we have seen that the gaps in satisfying these requirements still exist. We have shown that none of the assessed methodologies fulfill the criteria of adaptability, extensibility, dependability, and power-saving measures completely (as a whole). Hence, in the following text, we highlight the gaps in the 6G network. These are as follows: (i) handovers and interference for 6G network, (ii) security, (iii) network slicing, (iv) massive numbers of handover signals, (v) consideration of context, (vi) architectural advancement costs, (vii) communication, control, localization, sensing, and power consumption, (viii) dynamic network topology, (ix) assurance of no (zero) latency [114], (x) reconfiguration of metasurface, (xi) 6G network and pertinent network protocol stacks, (xii) optimized handoff strategy [115; 116], and (xiii) edge node pattern. These identified gaps have been tackled by researchers in the following ways: (i) addition of control and data plane in D2D, (ii) utilization of clean state strategies, (iii) deep learning, (iv) provision of seamless service through edge computing, (v) effective signaling in the core network, (vi) incorporation of SDN and NFV for DMM, and (vii) MM on-demand bases [6]. To sum up the discussion (Section 5), we first provided the 5G architecture (based on services) and the classification of the different procedures that have been investigated, as seen in Figure 1[117]. Succeeding that, we conducted qualitative research on 3 GPP 5G MM approaches and initiatives regarding the worth of MM mechanisms for 5G and future networks. Subsequently, we presented Table 4 (by reviewing Table 2), in which we specified the method where each of the discovered mechanisms fulfill the criteria of dependability, adaptability, extensibility, and power-saving. We also included a list of the sources (reference articles) that helped to compile Table 4, as provided in Section 5. According to understanding from the above discussion and literature review as depicted in Table 4, we concluded that none of the discussed MM mechanisms completely fulfill the mentioned requirements (adaptability, dependability, extensibility, and power saving) of Table 1. We also revealed the various gaps/challenges of MM mechanisms for 5G and future networks. Further, we presented a brief discussion on possible solutions that can help describe these gaps/problems. Next, we demonstrated an innovative mapping between the gaps and potential solutions in Table 5. Moreover, we also mentioned the metrics for qualitative investigation (requirements mentioned in Table 1). This, as a result, supported the completeness of our current discussion. Henceforth, in the subsequent section, by applying the implications from Sections 2-5 and Table 5, we suggest an architecture/framework for MM mechanisms. Figure 1: Organization of the innovative mobility management approaches in the 5G design.