IIS 10.0 is Microsoft's web server software used to host websites, web applications, REST APIs, and web services on Windows. It is included with Windows Server 2016/2019/2022 and Windows 10/11 (Professional and Enterprise editions as an optional feature). 

What IIS Does

Think of IIS as a receptionist for web requests:

  1. A user enters a website URL (e.g., https://example.com).

  2. The request reaches the IIS server.

  3. IIS determines which website or application should handle the request.

  4. The application processes the request (if needed).

  5. IIS sends the response (HTML, JSON, images, files, etc.) back to the user's browser.

Browser
   │
HTTP/HTTPS Request
   │
   ▼
+------------------+
|    IIS 10.0      |
+------------------+
        │
        ├── Static files (HTML, CSS, JS, Images)
        └── ASP.NET / .NET Application
                 │
             Database
                 │
        Response to Browser

Main Components

1. Websites

A website in IIS is a collection of web pages and applications.

Example:

  • Company website

  • School portal

  • E-commerce website

2. Application Pool

An Application Pool isolates applications from one another.

Benefits:

  • If one application crashes, others continue running.

  • Better security.

  • Better resource management.

3. Worker Process (w3wp.exe)

Each application pool runs inside a Worker Process, which processes incoming requests.

4. Virtual Directory

A virtual directory maps a URL to a physical folder.

Example:

URL:
https://company.com/images

Physical Folder:
D:\CompanyFiles\Images

Features of IIS 10.0

Some important features include:

  • HTTP/2 support for faster web communication and reduced latency.

  • HTTPS/SSL support for secure encrypted communication.

  • Application Pool Isolation for stability and security.

  • Request Filtering to block malicious requests.

  • URL Rewrite for friendly URLs and redirects.

  • Logging for monitoring traffic and troubleshooting.

  • Authentication options including Windows Authentication, Basic Authentication, and Anonymous Authentication.

  • FTP Server support.

  • PowerShell management for automation.

  • Wildcard Host Headers to simplify hosting multiple subdomains. 

Authentication Methods

IIS supports several authentication mechanisms:

Authentication Use Case
Anonymous Public websites
Windows Authentication Internal company applications (Active Directory)
Basic Authentication Simple username/password (typically with HTTPS)
Client Certificate High-security applications

IIS Folder Structure

Example:

C:\
 └── inetpub
      ├── wwwroot
      │      ├── index.html
      │      ├── images
      │      └── css
      └── logs

  • wwwroot is the default folder for website files.

  • logs stores IIS access logs.

Ports Used

Port Protocol Purpose
80 HTTP Normal web traffic
443 HTTPS Secure web traffic
21 FTP File transfer

Common IIS Manager Features

Using IIS Manager, administrators can:

  • Create websites

  • Configure application pools

  • Bind domains

  • Install SSL certificates

  • Configure authentication

  • View logs

  • Restart websites

  • Manage FTP sites

Advantages of IIS 10.0

  • Easy graphical management.

  • Excellent integration with Windows Server and Active Directory.

  • Optimized for ASP.NET and .NET applications.

  • Strong security features.

  • High performance and scalability.

  • Suitable for enterprise environments. 

Common Uses

IIS is commonly used to host:

  • ASP.NET Core web applications

  • ASP.NET MVC websites

  • REST APIs

  • Internal business applications

  • SharePoint (with supported configurations)

  • Web services

  • Static websites

 

credits: (Microsoft Learn)