How to turn off login for Sterling exposed web services in Sterling Selling and Fulfillment Suite?

Answer

Without authentication, Application Programming Interface (API) invocation of the web service call is not recommended. Its a security violation.
In case this is still required as per the implementation the below changes would serve the use case:

1. Set the sandbox.cfg variable SUPPRESS_JAXWS_HANDLERS=true
   Login call on webservice invocation is happening form the DefaultLogicalHandler.
   By setting SUPPRESS_JAXWS_HANDLERS=true handler chain will not get called.
   
   
   
2. Set yfs property api.security.token.enabled=N to disable API token validation.
   
   However. this does not disable security across all the channels. You will still have to validate through login page/api to access the application. This will only suppress the extra validation check for every API invocation(impacting API calls made through API tester and direct API access).
   
   Disabling the login validation specifically for web services call is not possible as API framework does not know that API is being executed within a web service call.