# Trusted Data Access Control Based on Logistics Business Collaboration Semantics
## 6 Use Case  
To evaluate the effectiveness and practicability of the proposed trusted data access control mechanism, grounded in the semantics of collaborative logistics business process, we conducted a case study within a logistics business scenario. We focused on a logistics collaboration network in Linyi City, involving carriers, suppliers, consignees, and warehousemen. These entities required sharing data and collaborating throughout the business process. For example, Supplier A and Carrier B might need to share access credentials and permission lists through multiple intermediaries for data transmission and sharing. Traditional approaches to this scenario often face challenges such as inadequate data security, inefficient data sharing, and trust issues among partners. However, the proposed model addresses these challenges effectively by assigning standard semantic tags like \"shipping location\" and \"goods status\" to share data. This enables the development of a fine-grained access strategy, allowing the data requester to accurately access allowed data, thereby ensuring data security and integrity. In our use case, User A is identified as a supplier, while Users B and C are warehousemen. All three users initiate access requests to the shipper information field of shipment number 2202004319 within Company A during working hours via an internal network. Notably, User C is in a situation that necessitates privileged access. To regulate access to the shipper information field, Company A formulates two policies, as follows:  
_Rule1 = Subject(?x) Object(?y) Shipper(?a) hasRole(?x,?a) Shipper_Information (?y) Worksite(?b) WorkingHour(?c) hasTime(?x,?c) hasLocation(?x,?b) -> permit(?x,?y)_  
Following Rule1, if the role of entity x is the shipper and the access request to shipper information field y is begun through the intranet during working hours, it is judged that entity x is permitted to access shipper information field y. _Rule2 = Subject(?x) Object(?y) Warehouse_man (?a) hasRole(?x,?a) Worksite(?b) Shipper_Information (?y) WorkingHour(?c) hasTime(?x,?c) hasLocation(?x,?b) -> deny(?x,?y)_  
If the role of entity x is the warehouseman, and an access request to shipper information y is begun through the intranet during working hours, then x is denied access to shipper information y. Due to the system automatically adding a \"privilege\" attribute for each policy result that is 'deny', an additional policy is introduced, as shown in Rule3. _Rule3 = Subject(?x) Object(?y) Warehouse_man (?a) hasRole(?x,?a) Worksite(?b) Shipper_Information (?y) WorkingHour(?c) hasTime(?x,?c) hasLocation(?x,?b) emergent(?x, true) -> permit(?x,?y)_  
If the role of entity x is a warehouseman whose access request is for shipper information field y, and x in particular is really in an emergency situation, it is determined that entity x allows access to shipper information y. Based on the access control rules defined above, determine whether the three users are allowed to access the shipper information field. According to the above scenario, experiments are conducted on traditional Ontop and AC_Ontop, and the results of the experiments are shown in Table 4. The results of the study show that AC_Ontop successfully enhances the security of the data while maintaining the accuracy of the original data query service, which implies that the new addition of the access control model does not negatively affect the data retrieval but rather strengthens the security of the data. \begin{table}
\begin{tabular}{l l l l} \hline \hline
**OBDA** & **Test User** & **Expected Results** & **Test Result** \\ \hline AC\_Ontop & User A & permit & permit \\  & User B & deny & deny \\  & User C & permit & permit \\ Ontop & User A & permit & permit \\  & User B & permit & permit \\  & User C & permit & permit \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Ontop and AC_Ontop test results. This section also tests the data query time and access inference time separately.