What property does soapui property window refer to? Is it the http request properties?

I'm trying to do a web service testing using SOAPUI. When I try to add the username and properties in the SOAPUI property window, I am getting the response. However, when i try to add the same username and password in the SOAP header in my request xml using tag, I'm getting the HTTP401 unauthorized error. I'm trying to understand how does SOAPUI achieve this. Could anyone please navigate me through this error. Thanks.