# Addressing ZSM Security Issues with Blockchain Technology
## 7 Assessment of Blockchain and DAG Platforms to Be Used for the ZSM-Solution Implementation
### Assessment of Blockchain/DAG Platforms  
Having examined the blockchain and DAG DLTs in the previous subsection, we proceed to the identification of their main characteristics in Table 2, which directly affect their suitability for our use case scenario. The columns of the table present the main attributes that describe the DLT's functionality while at the bottom of the table, the row with the ideal solution defines the properties of the most suitable solution for our scenario. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Solution** & **Public–** & **Permissioned–** & **Consensus** & **Support** & **Support** & **Support** & **Support** \\  & **Private/Consortium** & **Permissionless** & **Type** & **of SCs** & **of Tokens** & **of Oracles** \\ \hline \hline HLF & Private/Consortium & Permissioned & CFT (Rafi) or BFT (pBFT) & Yes & Yes & Yes \\ \hline Quorum & Private/Consortium & Permissioned & CFT (Rafi) or BFT (IBFT) & Yes (private SCs) & Yes & Yes \\ \hline R3 Corda & Private/Consortium & Permissioned & CFT (Rafi) or BFT (pBFT) & Yes (private SCs) & Yes & Yes \\ \hline IOTA & Public & Permissionless & FPC & Yes & Yes & Yes \\ \hline Hedera Hashgraph & Public & Permissioned & Hashgraph & Yes & Yes & Yes \\ \hline Ideal solution & Private/Consortium & Permissioned & CFT—rapid convergence & Yes & Yes & Yes \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Suitability of the examined blockchain and DAG solutions. Comparing each of the discussed solutions with the ideal one, we observe that every solution supports SCs, tokens and oracle mechanisms. However, in the Quorum and R3 Corda, we are able to use private SCs and implement private transactions if necessary. This is an extra feature that can be used to add extra functionalities to our solution in the future. For instance, some NPs in the network may sign an agreement of cooperation and fulfill requests with special terms which they might not want to unveil to other NPs in the network. Furthermore, the blockchain solutions implement private/consortium and permitted blockchains which are the ideal characteristics of the network to be adopted in our scenario. On the contrary, IOTA and Hedera Hashgraph support only public implementations while the IOTA network allows access to anyone as it is a permissionless network. These characteristics decrease the suitability level of those solutions for our use case and should be modified. In addition, the ideal solution should use a crash fault tolerant consensus mechanism with high convergence time in order to ensure the high availability of the system and achieve high transaction validation numbers, considering that the likelihood of a malicious participant is low. As illustrated in Table 2 the blockchain-based solutions can use consensus mechanisms with these features by implementing the Raft algorithm. However, DAG-based solutions use the FPC and Hashgraph mechanisms which present higher transaction validation speed which seems ideal for our use case. In terms of performance, the DAG solutions present higher numbers (transaction throughput) than the blockchain ones, and therefore, they are considered more suitable for our use case where the transaction number is expected to be extremely high. The scalability of the DLT solution is also a significant factor that plays a crucial role in the selection of the ideal solution. As was mentioned in previous subsections, the blockchain solutions present scalability issues as every node holds a full copy of the ledger which increases as new transactions are validated. Nevertheless, DAG nodes store only parts of the graphs, and therefore, they scale well when the transaction number increases. Hence, they are considered more scalable than blockchain solutions. To conclude, the qualitative assessment of blockchain/DAG platforms on which the prospective developer could build the ZSM-oriented solution, currently, none of the examined networks fulfill the criteria to become the ideal solution for our use case.