Web Service Runtime Configuration 
Security Settings Default
You can configure security settings for the service provider and service consumer for the runtime of Web services.
Settings
You make pre-settings for this during the Web service design in the Enterprise Services Repository for service interfaces and in the relevant AS ABAP or AS Java development environment.
ES Repository: Service Interface, under Security Profile
AS ABAP: Making a Web Service Secure
AS Java: Setting an Authentication Level, Setting the Transport Guarantee Level
Security Settings
In the runtime configuration, you can configure service providers individually or together using profiles. Not all security settings are available when using profiles.
Transport Level
HTTPS
HTTP communication that is secured with SSL (Secure Sockets Layer)
More information: Network and Communication Security
HTTP Authentication
The authentication information is found in the HTTP header.
User Name/Password (Basic)
X.509 Certificate
Authentication with an X.509 certificate.
Logon Ticket
Authentication with an SAP Assertion Ticket.
More information: HTTP Transport Level Authentication
Message Authentication
More information: Using Message Level Authentication
The authentication information is found in the SOAP header.
User Name/Password (Basic)
Authentication with WS Security UsernameToken
More information: WS Security UsernameToken
X.509 Certificate
Authentication with a signed SOAP message, user authentication by certificate
More information: WS Security XML Signature/Encryption
SAML Assertion
Authentication with a signed SAML 1.1 Assertion
More information: SAML Token Profile
Message Security/WS Security
The security settings affect the SOAP document.
WS secure conversion (for AS Java version February 2005, for AS ABAP version 1.3)
Messages are secured with a pre-defined symmetrical key. The key is re-used in further calls.
More information: WS SecureConversation
Add/Require Signature and Add/Require Encryption
Messages are secured with an XML signature and XML encryption with asymmetrical keys.
More information: WS Security XML Signature/Encryption
You choose one of the predefined security settings during the runtime configuration for the service consumer.
Recommended WS Security Scenarios
SAP has put together recommendations for you on combining authentication and transport guarantee mechanisms. You can also get information on what prerequisites you have to fulfill to implement the scenario in your systems.
More information: Recommended WS Security Scenarios