ASP.NET Core Runtime and Framework
Asynchronously Reading and Writing HTTP Requests and Responses
Improvements to HttpRequest handling
Asynchronously flushing a response
Support for await and Task-Based Asynchronous Modules and Handlers
Asynchronous HTTP modules
Asynchronous HTTP handlers
New ASP.NET Request Validation Features
Deferred ("lazy") request validation
Support for unvalidated requests
AntiXSS Library
Support for WebSockets Protocol
Bundling and Minification