 The key addition to the traditional postmarking technology was integrity of the electronically postmarked item, meaning any kind of falsification and tampering will be easily and definitely detected.Additionally, content confidentiality is guaranteed since document certification is carried out without access or reading by the postal operator.The EPCM will eventually be available through the UPU to all international postal operators in the 191 member countries willing to be compliant with this standard, thus granting interoperability in certified communications between postal operators.