# Leveraging Blockchain Technology for Secure 5G Offloading Processes +
## 3 Blockchain-Based Secure 5G Offloading Mechanism
\begin{table}
\begin{tabular}{c c} \hline \hline
**Issues from [23; 49]** & **Proposed Solutions** \\ \hline It does not really deep into the technical details of using Blockchain for offloading processes. & This paper includes deep technical details about Blockchain and SSI techniques considered for enhanced security of the offloading process. \\ \hline It considers an InterPlanetary File System (IPFS) decentralized storage where private information is stored without guaranteeing its privacy. & The information required for the offloading process is stored in a permissioned Blockchain, taking advantage of its inherent security features. \\ \hline Lateral communications among different operators are required, meaning that a prior mutual relationship is needed. & Prior communication among operators is not needed as it is orchestrated through Blockchain transactions and events. \\ \hline The validation is done in an Ethereum public network, where throughput, latency, scalability, and privacy are not optimized. & Hyperledger permissioned network is considered for enhanced throughput, latency, and scalability. \\ \hline User authentication credentials need to be shared among operators, which increases the likelihood of interception and thus problems of unauthorized access or exposure of private information. & SSI-based authentication will be considered avoiding authentication credentials sharing and letting the user to totally control and manage its identity. \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Issues and solutions from the state-of-the-art. * SSI agent which will manage the identity of the user equipment through verifiable credentials. The identity issuance (primary operator) and the validation (secondary operator) are executed. On the other hand, each user equipment requires new logic related to the SSI-based authentication on secondary operators before connectivity being updated from the primary to the secondary operator:  
* SSI controller which will manage the user equipment identity received from the primary operator to be offloaded to the secondary operator. * SSI agent which will manage the reception and secure storage of the received credential from the primary operator as well as the credential sharing for being authenticated in the secondary operator. Figure 2 describes the high-level operation of the secure 5G offloading mechanism leveraging Blockchain technology. On the one hand, all the operators (5G or other technologies) participating in this mechanism (those registered in the marketplace) will periodically update their network state in the marketplace in order to keep their availability updated for offloading processes from other operators. This process requires their already existing network discovery logic (this logic will be different for each technology) to periodically notify the new offloading manager about the updates. The offloading manager will update the details in the marketplace through the wallet. Figure 1: Secure 5G offloading architecture. Figure 2: Secure 5G offloading operation diagram. On the other hand, when a primary operator detects that an offloading process for a connected user equipment is required due to a shortage of available resources, low coverage, or low quality detected in the network, an offloading process is requested to the offloading manager, which defines the requirements the new (secondary) operator must fulfill for a particular user equipment. These requirements could be related to minimum resources, location, etc. The request is then sent to the marketplace deployed in a Hyperledger Fabric Blockchain network where the search for the most suitable secondary operator is done (see Section 3 for internal details). Once selected, a Blockchain event is sent from the marketplace to the primary and selected secondary operators to notify them about the offloading process for the particular user equipment. When the event is received by the primary operator, it issues a new credential with information about the new offloading agreement.