Samsung IAP ISN Header

The Samsung In-App Purchase (IAP) Instant Server Notification (ISN) is a JSON Web Token (JWT) that uses a JOSE (Javascript Object Signing and Encryption) header. The header lists properties related to cryptographic operations applied to a claim set.

The header is encoded in base64 format. When it is decoded, it is in JSON format.

Example encoded header

eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9

Example decoded header

{
   "alg" : "RS256",
   "typ" : "JWT"
}

JSON Properties

Name	Value	Description
alg	string	Algorithm used to generate the JWT signature. By default, ISN supports RS256 (SHA256withRSA).
typ	string	Token type. This is always JWT.