Patent ID: 7986780

Claim:
A system to contribute to creating a substring of a string, the system comprising: a communication unit to receive an encrypted representation of a second share of the string, the second share of the string being combinable with a first share of the string via a combining operation to generate the string; and a processing unit to, using a processor, rearrange a representation of the encrypted representation of the second share of the string using a first share of a start value of the substring to generate a rearranged representation of the encrypted representation of the second share of the string, the start value being a result of a function of the first share of the start value and a second share of the start value, the string not being revealed to the system; compute a decrypted string by decrypting a received rearranged representation of the encrypted representation of the first share of the string; rearrange the decrypted string using the first share of the start value of the substring, and create a first share of the sub string by identifying elements of the first share of the substring with a number of leading elements of the rearranged decrypted string, the first share of the substring being combinable with a second share of the sub string via a combining operation to generate the sub string and the number of leading elements being identical to a first share of a length value of the substring, the length value of the substring being a result of a function of the first share of the length value and a second share of the length value; the communication unit further to send the rearranged representation of the encrypted representation of the second share of the string to a further system.