OAuth2 Token Exchange RFC8693

OAuth2 Token Exchange RFC8693 is a protocol that addresses the challenges of securely propagating identity and permissions through API gateways in the context of microservices. It enhances API security by enabling the exchange of security tokens between OAuth2 authorization servers and API gateways, allowing the latter to authenticate and authorize themselves while maintaining user-specific information and permissions. Traditional methods like Auth Proxy and OAuth2 Client Credentials have limitations, such as potential security vulnerabilities and loss of user identity information, which the OAuth2 Token Exchange aims to overcome. By using a token-exchange grant, the protocol enables gateways to obtain unique tokens for each user request, dynamically reflecting the user's permissions and identity, thus standardizing API authentication and authorization mechanisms. This approach is considered an elegant solution for managing complex identity and permission propagation scenarios in modern API architectures.