1. A method for processing symbols by a first computerized entity, the method comprising: receiving, by a first computerized entity and over a communication network, text that comprises multiple random tokens and a plurality of plaintext symbols; wherein the multiple random tokens are generated by a second computerized entity; wherein a value of each random token that represents a plaintext symbol is responsive to values of random tokens that represents plaintext symbols that have a lower lexicographic value than the plaintext symbol; and processing the text by the first computerized entity.