Every organisation that transmits or stores sensitive data over public networks is already at some level of exposure to the quantum threat—not because quantum computers capable of breaking current encryption exist today, but because adversaries can record encrypted traffic now and hold it until they do. This ‘harvest now, decrypt later’ (HNDL) dynamic means the clock on cryptographic migration started before the problem became technically urgent.
For Thailand, the implications are substantial. The country’s digital economy spans a modern interbank payment system, a growing e-government infrastructure, and tens of millions of citizens whose medical and financial records depend on cryptographic protections whose mathematical foundations—RSA and elliptic-curve cryptography (ECC)—are known to be vulnerable to quantum attack. Shor’s algorithm established in 1994 that a sufficiently large quantum computer could solve the problems underlying both schemes in polynomial time, rendering any key size considered secure today effectively breakable by a machine of that kind (Shor, 1994). As quantum hardware
development has continued to accelerate, the window for orderly migration has narrowed accordingly.
