# Evolution towards Smart and Software-Defined Internet of Things
## 5 Evolution of IoT Architecture
### 5G Technologies  
Comparisons of techniques for SDN and NFV in IoT are extended in Table 1 in a similar pattern. Justification for the comparison of various SDN and NFV solutions covered is given below in the same order. Interoperability is a critical challenge in IoT where multiple products of different vendors are connected. All solutions covered are partially compliant except the horizontal IoT theoretical model which by definition is compliant. As long as vertical IoT exists and applications remain domain-dependent, interoperability will remain a challenge. A secured environment is a fundamental requirement of IoT. Security, privacy, and trust become particularly challenging issues when things are connected to the global network. Only two of the eight solutions discussed, \"Full SDMN IoT with NFV\" and \"SDN IoT with Blockchain,\" can provide adequate security and privacy. IoT applications must be designed from the ground up to enable extensible services and operations. This means the ability to add new devices, services, and functions must be built-in without negatively affecting the quality of existing services. Out of the 10 solutions discussed, SDIoT is partially compliant, and scalability issues arise because it is hard to manage the large network in the case of a single SDSec logical element. An experimental evaluation is lacking. Flow-based QoS scheduling ensures that the various QoS parameters and metrics at the application, network, and perception layers are optimum. It has been found that all solutions that used SDN in conjunction with NFV provided enhanced flow-based QoS \begin{table}
\begin{tabular}{l c c c c c c c c c c c} \hline \hline
**Approach** & **Technology** & **IOP** & **SP** & **Scal.** & **QoS** & **EES** & **Vit.** & **Het.** & **R** & **M** & **St.** & **MT** \\ \hline IOT Gateway & IoT & PC & PC & N & NA & NA & N & PC & NA & NA & NA & NA \\ \hline Nanotechnology & IoT & PC & N & PC & NA & NA & N & PC & NA & NA & NA & NA \\ \hline Task Computing Framework & IoT & PC & N & N & NA & NA & N & N & NA & NA & NA & NA \\ \hline Tripple Based Distributed & IoT & PC & PC & N & NA & NA & N & N & NA & NA & NA & NA \\ \hline UBIWARE & IoT & PC & N & NA & NA & NA & N & PC & NA & PC & N & NA \\ \hline SOA & IoT & PC & PC & PC & NA & NA & N & PC & NA & NA & PC & NA \\ \hline GSN & IoT & PC & N & PC & NA & NA & N & PC & NA & NA & NA & NA \\ \hline Fosstrak & IoT & N & N & NA & NA & NA & N & PC & NA & NA & PC & NA \\ \hline TinyREST & IoT & PC & N & NA & NA & NA & N & N & NA & NA & NA \\ \hline ROS & IoT & PC & NA & NA & NA & N & PC & NA & NA & NA & NA \\ \hline WSO2 Stratos & IoT/PaaS & PC & NA & PC & NA & NA & N & PC & NA & NA & NA & PC \\ \hline Wireless Gateway (WG) & IoT & PC & NA & PC & NA & NA & N & PC & NA & NA & NA & NA \\ \hline Smart Garbage Bin (SGB) & IoT & PC & PC & NA & NA & N & N & PC & PC & NA & NA \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Traditional IoT Approaches. as they implement a heterogeneous cross-layer approach. Using fog computing with SDN also provides better flexibility to manage the QoS for various applications. Based on the literature review, it is found that IoT solutions that work on SDN in conjunction with NFV offer energy-efficient scheduling as they implement a heterogeneous cross-layer approach [84]. Figure 7 shows a software architecture for the 5G IoT network. There is data transfer to and from SD-BSs to the sensors, actuators, RFID tags, detectors, and other smart devices. This data is further transferred to the smart core network through SD-GWs [62]. Finally, different sectors such as smart grid, smart city, smart transportation are managed and monitored intelligently. These sectors can be further infused with blockchain and edge computing to enhance security, scalability, latency, and efficiency. The SDN-based, NFV infused IoT model requires to be injected with higher degrees of intelligence to enable the existing infrastructure and approaches to achieve better compliance and show higher performance and improved results.