Glossary You Are @ Home/ Glossary A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z K Key Custodians The persons, assigned by the security administrators of trading partners, that send or receive a component of either the master key or exchange key used to encrypt data encryption keys. This control technique involves dual control, with split knowledge that requires two key custodians.