Security of Web Services, Agents and Sequantial Calling of Web Services

Question

I want to ask about the secure invocation of web services and the role of agents.
Suppose that I have greet() web service:
public String greet() {
String S1=sayHello(); // A web service, actually its proxy
String S2=sayGoodMorning(); // A web service, actually its proxy
return S1+" "+S2;
It calls two other webservices and they return "HELLO" and "Good Morning". Also assume that I need to secure all my web services but I need these calls to work!
I put an agent in front of those two web services and require them to check a SAML token. I also attach an agent to greet() to authenticate the inbound and sign and add SAML token for outbound.
But I think these two calls fail because the SAML is not created on each call. (Is it?)
How can I make those two calls, secure each web service and at the same time keep the security code out of business code, in other words keep my web service security agnostic?
Thank you in advance.
Best Regards
Farbod

Answer 1

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