关于认证码的一些特征

On some characteristics of authentication codes

刻画了双完备认证码的结构；给出了ｒ阶完备认证码的定义及判定ｒ阶完备认证码的一个充要条件，并由组合设计构造了ｒ阶完备认证码．

The construction of doubly perfect authentication codes is presented. A new difinition of r order perfect authentication codes is proposed. The condition necessary and sufficient to determine r order perfect authentication codes is obtained, and by use of combinatorial design the r order perfect authentication codes is constructed.