| SSPI Function Call | Description | GSSAPI Function Call | Description |
| EnumerateSecurityPackages | Allows you to discover the supported security packages. | gss_indicate_mechs | Returns a list of supported mechanism OIDs. |
| gss_import_name | Converts string format of a name to a normalized binary format. | ||
| InitSecurityInterface | Retrieves a pointer to a dispatch table after security.dll has been loaded. | ||
| AcquireCredentialsHandle | Gets a handle to existing credentials of a security principal. | ||
| AcceptSecurityContext | Server-side call used to create a security context based on a client message. | gss_accept_sec_context | Accept an inbound (server) security context. |
| InitializeSecurityContext | Client-side call used to authenticate (initialize the security context). | gss_init_sec_context | Initiates an outbound (client) security context. |
| DecryptMessage | Used for message decryption—not necessary with SSH. | gss_unwrap | "Decapsulates, decrypts, and verifies the integrity check of a message." |
| EncryptMessage | Used for message encryption—not necessarywith SSH. | gss_wrap | "Signs, encrypts, and encapsulates a message." |
| MakeSignature | Creates a digital signature based on a security context and a message. | gss_get_mic | Generates a digital signature (integrity check) over a message. |