<Tr> <Th> First published </Th> <Td> 1998 (ANS X9. 52) </Td> </Tr> <Tr> <Th> Derived from </Th> <Td> DES </Td> </Tr> <Tr> <Th_colspan="2"> Cipher detail </Th> </Tr> <Tr> <Th> Key sizes </Th> <Td> 168, 112 or 56 bits (keying option 1, 2, 3 respectively) </Td> </Tr>

3des (triple data encryption standard) is based on which of the following