00309nam a2200109Ia 450000500170000000800410001708200170005810000230007524500640009825000120016226000250017420260325112251.0260325s9999||||xx |||||||||||||| ||und||  a005.82 St18C  aStallings, William 0aCryptography and network security : principles and practice  a7th ed.  aNoidabPearsonc2018