3ANSI x9.17 (Revised). Americannational standard for finan- cial institution key management[ S]. 1985.
4Ghodosi H, Pieprzyk J, Safavi-Naini R, et al. On construc- tion of cumulative secret sharing schemes [ C ]//Proc of ACISP. Is. 1. ] :~s.n. ] ,1998.
5Thomas R, Sandhu R. Task-based authorization controls (TBAC) :A family of models for active and enterprise-ori- ented authorization management[ C ]//Proc of eleventh inter- national conference on database security. Lake Tahoe, Cali- fornia,USA: [ s. n. ], 1997.
