Research Article

RTBAC: A Risk-Aware Topic-Based Access Control Model for Text Data with Paragraph-Level Authorization

Algorithm 1

RTBAC overall execution process.
Input: User u, target data dtar, base set bs(u), access mode am
Output: Access rights r(u, dtar, bs(u), am)
(1)Use topic system to compute the content similarity SIM(u, dtar) between u and dtar;
(2)if SIM(u, dtar) < TSIM then
(3) r(u, dtar, bs(u), am) = ø;
(4)else
(5)if am = 0 then
(6)  Add dtar and the corresponding paragraphs to the temporarily accessible document-paragraph collection DPtmp;
(7)else
(8)  Add dtar and other documents with content similar to dtar and the corresponding paragraphs to DPtmp;
(9)end
(10) Compute u’s access risk Riska(u) and historical risk Riskh(u);
(11) Use Riska(u) and Riskh(u) to compute the user category of u;
(12) Compute r(u, dtar, bs(u), am) and consume the corresponding risk quota of u;
(13)end
(14)Return r(u, dtar, bs(u), am)