你如何在你的DDD中编写身份验证，角色和安全性？

How do you implement Roles and Security in your C# Domain Driven Design projects? We have some debate raging on whether it should be implemented by the calling application (ASP.NET MVC) or in the Domain Model itself (model entities and services). Some argue that it should be in the web site itself since that's where the authentication already exists. But that means you have to re-implement security every time you integrate with the core business systems.How do you implement Roles and Security in your