Samsung IAP ISN Stucture
The Samsung In-App Purchase (IAP) Instant Server Notification (ISN) is a JSON Web Token (JWT) structure and consists of three parts, separated by a dot ("."), and is base64 encoded:
You can use JWT open source libraries or implement your own solution to parse the notification. For more information about JWT, see RFC 7519.
Example ISN
eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJpc3MiOiJpYXAuc2Ftc3VuZ2FwcHMuY29tIiwic3ViIjoiRVZFTlRfTkFNRSIsImF1ZCI6WyJjb20ucGFja2FnZS5uYW1lIl0sIm5iZiI6MTcxNzIwNCwiaWF0IjoxNzE3MjA0LCJkYXRhIjp7InNlbGxlck5hbWUiOm51bGwsImNvbnRlbnROYW1lIjoiTWFydGluZSJ9LCJ2ZXJzaW9uIjoiMi4wIn0.HKoLD9adhbbDoFhjBkoYP1PxWro6c9pPobM5OLPrQW_mfzXO7u-iND5J-oWyMVwmUQEdJBXfwFMyU-BFU4OJyicQFmpbPKxxJMgp8N78jBtK-0wxvk4l_o7Q7A2h6JMe3rVelMqfYh8eD667MfqEc2Gkk0STK5rGk6zIhXWI_J1ajbgbHLK6kUxwUXTqxNUF4vBfSauWOrwJgmPM6RhmIm55WzS5p-5RqRBrqqwNF-pYvxFKkJRSTamCcfMAnfL_TVIZLRYkRd3ofw0Tvtl1kdyJhOKq5NbF4iaNDRt2qAVuDqOLLowXkDbRvWvu23zsQckBfH0omLQtC1gY_-s6pA