# 5G Support for Industrial IoT Applications--Challenges, Solutions, and Research Gaps
## 8 IoT Security in 5G
### Low-Powered Security Enhancements in 5G  
Although authentication is traditionally not a part of the CIA triad, it plays an important role in fulfilling these requirements. Authentication scheme has also improved and been more flexible in 5G networks, mostly due to low-latency requirements. To meet low latency needs, an SDN-based fast authentication scheme can be used that relies upon weighed secure-context-information. After a full (and more computation intensive) authentication, user-inherent physical layer attributes are used for identification to provide seamless handover authentication between cells, or even trusted parties [92; 93].  
As 5G applications can transmit massive private and/or critical data, **confidentiality** has to be ensured in these use-cases. 5G puts a lot of emphasis on Physical Layer Security (PLS) solutions as well, thus instead of relying upon only high-level data encryption methods, PLS support can enhance defense mechanisms in this field (i.e., against jamming). There are multiple proposed techniques such as power control, artificial noise, and multi-level cryptography methods; however, most of them require more computation capability than a typical IoT node has. Relaying is considered as a lightweight solution to ensure certain level of data confidentiality in 5G for IoT applications [93]. Additionally, there are numerous lightweight cryptography methods that can be applied [94]; however, there is no standard about which one should be used, since it greatly depends on the use-cases.  
**Availability** issues--in wireless networks these are related to DoS attacks and performed by jamming in most cases. As we mentioned before, using spread-spectrum techniques is an efficient way to avoid jamming, although they can not be applied in IoT nodes with limited resources (e.g., sensor). In this field 5G does not deploy revolutionary new solutions--besides a few ones--although [PERSON] et al. in [95] proposed a solution where a fusion center defenses nodes from jamming attacks over a 5G network.  
\begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Security Threats** & **Target Point/Network Element** & \multicolumn{4}{c}{**Effected Technology**} & \multirow{2}{*}{**Privacy**} \\  & **SDN** & **NFV** & **Channels** & **Cloud** & \\ \hline DoS attack & Centralized control elements & ✓ & ✓ & & ✓ & \\ Hijacking attacks & SDN controller, hypervisor & ✓ & ✓ & & \\ Signaling storms & 5G core network elements & & ✓ & ✓ & \\ Resource (slice) theft & Hypervisor, shared cloud resources & & ✓ & & ✓ & \\ Configuration attacks & SDN (virtual) switches, routers & ✓ & ✓ & & & \\ Saturation attacks & SDN controller and switches & ✓ & & & & \\ Penetration attacks & Virtual resources, clouds & & ✓ & & ✓ & ✓ \\ User identity theft & User information data bases & & & & ✓ & ✓ \\ TCP level attack & SDN controller-switch communication & ✓ & & ✓ & & ✓ \\ Man-in-the-middle attack & SDN controller-communication & ✓ & & ✓ & & ✓ \\ Reset and IP spoofing & Control channels & & ✓ & & ✓ \\ Scanning attacks & Open air interfaces & & & ✓ & & ✓ \\ Security keys exposure & Unencrypted channels & & ✓ & & & ✓ \\ Semantic information attacks & Subscriber location & & ✓ & & ✓ \\ Timing attacks & Subscriber location & & & ✓ & ✓ \\ Boundary attacks & Subscriber location & & & & ✓ \\ IMSI catching attacks & Subscriber identity & & ✓ & & ✓ \\ \hline \hline \end{tabular}
\end{table}
Table 8: Security challenges in 5G technologies [89].