The Payment Services Directive 2 (PSD2) aims to simplify online payments by opening up the payment ecosystem, but also introduces new regulations such as strong customer authentication. This requires payment service providers to implement dynamic linking, which involves generating unique authentication codes specific to each transaction amount and recipient. The code must be displayed to the payer at the time of the transaction, and any changes to the amount or payee result in invalidation of existing codes. Additionally, payment service providers must adopt security measures to ensure confidentiality, authenticity, and integrity of all data exchanged during the authentication process. Proper compliance with PSD2 is crucial for online and mobile commerce to continue growing, and payment service providers must balance security and compliance with user experience and scale.