6. A system for securing data between a client device and a server, the system comprising: an intermediate module device configured to: obtain input text; process the input text by applying an order-preserving transformation to obtain processed text, said order-preserving transformation comprising: generating order information by applying an order-preserving and secret-key dependent function in the form of a numerical monotonously increasing to information related to said input text, said order information indicative of a relative order of the input text within a set of possible input texts according to a collation rule, the applying of the function including: obtaining an input numeric value based on at least a portion of the input text; providing an input range and an output range; dividing the input and output ranges into two input ranges and two output ranges based on a secret key; selecting a pair of input and output ranges from the divided ranges according to which of the input ranges includes the input numeric value; iteratively repeating the dividing and selecting steps until the output range is smaller than a predetermined parameter, said output range being a final output range; and returning an output numeric value lying within the final output range; and transmit the processed text to the server.
6. A system for securing data between a client device and a server, the system comprising: an intermediate module device configured to: obtain input text; process the input text by applying an order-preserving transformation to obtain processed text, said order-preserving transformation comprising: generating order information by applying an order-preserving and secret-key dependent function in the form of a numerical monotonously increasing to information related to said input text, said order information indicative of a relative order of the input text within a set of possible input texts according to a collation rule, the applying of the function including: obtaining an input numeric value based on at least a portion of the input text; providing an input range and an output range; dividing the input and output ranges into two input ranges and two output ranges based on a secret key; selecting a pair of input and output ranges from the divided ranges according to which of the input ranges includes the input numeric value; iteratively repeating the dividing and selecting steps until the output range is smaller than a predetermined parameter, said output range being a final output range; and returning an output numeric value lying within the final output range; and transmit the processed text to the server. 8. The system of claim 6 , wherein said intermediate module device is configured to generate said order information based on a truncated version of the input text.