An electronic machine readable travel document (eMRTD), primarily the electronic passport (ePassport) will be of maximum use in facilitating international travel providing the introducing State considers how these electronic documents are validated at foreign borders.
This is often overlooked by national authorities that introduce eMRTDs, mainly due to a lack of understanding the mechanisms of the underlying Public Key Infrastructure (PKI) and the central role of the ICAO Public Key Directory (PKD) in facilitating the validation process at international borders. This leads to the issuance of eMRTDs that cannot be electronically validated at foreign borders, thus loosing the main advantage of being electronically readable.
Without sharing critical information with other States via the ICAO PKD (or with huge efforts via bilateral agreements), an electronic MRTD has little or no benefit as compared to a non-electronic one.
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