Authentication Types - alpacahq/alpaca-trade-api-csharp GitHub Wiki

Both Alpaca APIs (REST and streaming) supports two types of authentication:

• Using the id/secret pair - use the Alpaca.Markets.SecretKey class instance in the appropriate places.
• Using the OAuth token - use the Alpaca.Markets.OAuthKey class instance in the appropriate places.

Both classes are inherited from the Alpaca.Markets.SecrityKey abstract class and if a method has this type in the signature it means that both concrete classes can be used as authentication tokens.