Server in ASP.Net Core

An ASP.NET Core app runs with an in-process HTTP server implementation. The server implementation listens for HTTP requests and surfaces them to the app as a set of request features composed into an HttpContext.

Default web server in ASP.Net Core

Kestrel is the default web server specified by the ASP.NET Core project templates.

To understand Kestrel, lets look into below figure(Ref: Microsoft Documentation)

By itself as an edge server processing requests directly from a network, including the Internet.

With a reverse proxy server, such as Internet Information Services (IIS), Nginx, or Apache. A reverse proxy server receives HTTP requests from the Internet and forwards them to Kestrel.

Kestrel with IIS or IIS Express

Kestrel server is the default, cross-platform HTTP server implementation.

IIS HTTP Server is an in-process server for IIS.

HTTP.sys server is a Windows-only HTTP server based on the HTTP.sys kernel driver and HTTP Server API.

In the same process as the IIS worker process (the in-process hosting model) with the IIS HTTP Server. In-process is the recommended configuration.

Kestrel server is the default, cross-platform HTTP server implementation.

Hosting Models in ASP.NET Core

There are 2 types of hosting models in ASP.NET Core i.e In-process Hosting and Out-of-process Hosting. Before ASP.Net Core 2.2 we have only one hosting model which is Out-of-process but after due to the performance we have In Process Hosting Model in 2.2+ versions

Summary

To summarise, Kestrel server is the default web server which is cross-platform and support SSL . Hope you picked up a thing or two.

Cheers!