# The Challenges and Compatibility of Mobility Management Solutions for Future Networks
## 5 Recent MM Techniques and 5G Architecture
### Design Aspects of 5G Related MM Mechanisms  
The literature [33; 70; 71] presents the development and design aspects of MM mechanisms in the 5G network. These mechanisms (on the basis of functionality) can be categorized as follows: (i) monitoring of user mobility [33], (ii) provision of multi-homing [33], (iii) novel session controlling methods, (iv) coverage of user plan [33], (v) twofold association and computation at edges [33], (vi) slicing in networks [22], (vii) congestion control and load balancing technique [33], (viii) new MM module (inter and intra next-generation handover) [33; 70], and (ix) device to device (D2D) mobility provision [72]. Furthermore, the aforementioned techniques can be enhanced by introducing the global view of network scenarios and softwarized solutions for 5G and future MM methods. Subsequently, we discuss these innovative MM mechanisms for 3 GPP in the following text. Now, in light of the discussion in Table 2 of Section 3, we identify the advantages and drawbacks of 3 GPP MM techniques in 5 G networks. These are as follows. **Advantages**  
- IPV6 multi-homing support [27]  
- Facility of service stability modes for various sessions [27]  
- Facilitation of event notifications, resource negotiation mechanisms, and monitoring of UE mobility at target RAT [27]  
- Provision of per-PDU session granularity, traffic direction, malleable session control, and roaming option [27]  
- Provision of handover for inter-RAT and intra-RAT [27]  
- Sound and well-defined 5 GC inter-working interface, i.e., N26 [27] and EPC  
- D2D level mobility provision [55; 71]  
- Provision for multi-RAT DC [27]  
- Provision for edge computing [27]  
- The network slicing information movement provision at the time of intra/inter-RAT mobility [27]  
- Network slicing provision for supporting on-demand MM  
- Potential to offer context cognizance via the slicing of the network [11]  
- Potential for handling core network burden by offering re-balancing philosophies and load balancing on the AMF [27]  
**Drawbacks**  
- The harmonization among D2D peers for sanctioning the well-organized MM techniques has not been explored. - Signaling at the time of handoff is not so optimal in the correspondence node. - Still, the fundamental approach for discovering any access point is based on received signal strength (RSS) [73]. - An integrated structure for cross-layer approaches, such as MR-DC (physical and MAC layer), MPTCP-SCTP (transport layer), and IPv6 multi-homing (network layer) working collectively, has not been explored. - Due to the single occurrence of user plan functionality (UPF) in IPV6 multi-homing, there is still a chance of SPoF [27]. According to the identified advantages and drawbacks of 3 GPP 5G MM mechanisms, we can justify the completeness of the parameters (dependability, adaptability, extensibility, and power consumption) in the following text along with the provision in Table 4.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Research Contribution**} & \multirow{2}{*}{**Solutions**} & \multicolumn{8}{c}{**Dependability**} & \multicolumn{8}{c}{**Adepability**} & \multicolumn{8}{c}{**Extensibility**} & \multicolumn{8}{c}{**Power Swing**} \\ \cline{3-14}  & & & &  
1. Dependability parameter considerations The following parameters of dependability fulfill the criteria for MM mechanisms for 5G and future networks based on our understanding and review of the literature. These are: 1. DL1: This parameter can fulfill the criteria by providing a congestion awareness feature in NAS. 2. DL2: This parameter can fulfill the criteria by introducing decentralization in MM mechanisms. 3. DL4: The criteria of ensuring the seamless handoff capability with the help of MR-DC and handoff mechanisms. 4. DL5: This parameter fulfills the dependability criteria by providing multiple flows and connections. 2.