Patent ID: 7694132

Claim:
A communications system comprising: a first computer having stored therein a function M and a first set of keys, each key within said first set of keys defining a series of values, said first computer configured to: a) receive a mail-destination and a sequence of original values O j ; b) based upon said mail-destination, select one of said keys from said first set of keys; c) using the function M and the selected key from the first set of keys, transform the sequence of original values O j to a sequence of transformed values E j , and, d) communicate the sequence of transformed values E j and a source identifier to a second computer: said second computer having stored therein a function M′ and a second set of keys, each key within said second set of keys defining a series of values, said second computer configured to: a) receive the sequence of transformed values E j and the source identifier; b) based upon said source identifier, select one of said keys from the second set of keys; c) using the function M′ and the selected key from the second set of keys, reconstruct the original sequence of values O j from the sequence of transformed values E j , and, d) based upon said destination address, select one of said keys from the second set of keys, e) using the function M and the selected key from the second set of keys, transform the sequence of original values O j , to a sequence of transformed values E′ j , and, f) communicate the sequence of transformed values E′ j and the source identifier to a third computer associated with said destination address; and, said third computer configured to: a) receive the sequence of transformed values E′ j and the source identifier; b) based upon said source identifier, select a key from a third set of keys; and, c) using the function M′ and the selected key from the third set of keys, reconstruct the original sequence of values O j , from the sequence of transformed values E′ j .