Electronic information is the core for electronic online transaction comprising electronic data, electronic message and electronic record, so that its protection is absolutely admitted as information which has the same status as paper based and signed document. Legal protection for electronic information will give legal certainly in the evidence framework if that electronic information fulfills requirements of validity, reliability and security. Electronic document gets security through the language of machine signature that is electronic siganture. Electronic signature appears because there is no standard method to sign a paper document containing certain writing, whether to use hand paper by using ink or other means. However, the authenticity of electronic document becomes an absolute thing to prevent conflicts in the future. In this online transaction, the authenticity becomes an absolute thing because although the transaction uses electronic documents, but the key concept or the core of evidence admission and the evidence value of electronic documents, which becomes the center of law is still the same as paper based documents.