.NET Core and .NET Framework are rewrites of the .NET components. .NET Core is cross-platform and has minimal dependencies, allowing it to run on Windows, Linux and MacOS. It uses CoreCLR as its runtime and CoreFX for its libraries. .NET Framework remains for traditional Windows development and is not going away.

1. .NET Core vs .NET
Framework
Wyn Van Devanter
@wynv
wyn.vandevanter@excella.com

2. Core
 Rewrite of the .NET components
 .NET Core 5 -> .NET Core 1.0
 ASP.NET 5 -> ASP.NET Core 1.0
 Entity Framework 7 -> Entity Framework Core 1.0
 .NET Framework is not going away
 Tried and true

3. Open Source
 https://github.com/dotnet/core
 https://github.com/aspnet/home
 https://github.com/aspnet/EntityFramework

4. Cross-platform support
Developers can target a single common set of libraries that are supported
by multiple platforms
 Windows
 OS X
 Linux
 Docker (Linux, Docker for Window Server)

5. Cross-platform development experience
Developers can build applications from various platforms
 Windows
 OS X
 Linux

6. Minimal Dependencies
 Use only the libraries you need within an application
 The libraries (CoreFX) have been built to have minimal dependencies

7. Minimal Dependencies - Benefits
 More modular
 Reduced impact of upgrades since only those packages used are affected.
 Smaller footprint
 Great for
 mobile apps that need a small footprint
 cloud-based apps that need many small applications running side-by-
side

8. .NET CLI
 DNX merged into the CLI

9. .NET landscape
SOURCE: http://www.hanselman.com/blog/ASPNET5IsDeadIntroducingASPNETCore10AndNETCore10.aspx

10. SOURCE: An update on ASP.NET Core 1.0 RC2, Scott Hanselman

11. .NET Core landscape
.NET Core Description Key Components
ASP.NET 5 to ASP.NET
Core 1.0
•Cross-platform
•Runs on top of .NET Core or the full .NET
Framework 4.6
N/A
Entity Framework
7 to Entity Framework
Core 1.0
•Lightweight rewrite of Microsoft’s ORM
•Built to work well in the cloud, various devices,
and traditional .NET applications
N/A
.NET Core 5 to .NET
Core 1.0
•Modular, cross-platform rewrite
•Some shared functionality
•Some missing, (i.e. library for working with
XAML-based UIs)
•Some added (i.e. cross-platform functionality)
•CoreCLR: runtime
•CoreFX: libraries
•CoreRT: .NET Native
runtime
•CLI: command-line
interface
DNX into CLI
Cross-platform command-line interface for
creating and managing .NET projects
N/A

12. ASP.NET performance
ASP.NET 4.6 perfsvr 57,843
32 threads, 256
connections
Generic
reusable
handler, unused
IIS modules
removed
CPU is 100%,
almost
exclusively in
user mode
NodeJS perfsvr 106,479
32 threads, 256
connections
The actual
TechEmpower
NodeJS app
CPU is 100%,
almost
exclusively in
user mode
NodeJS perfsvr2 (Linux) 127,017
32 threads, 512
connections
The actual
TechEmpower
NodeJS app
CPU is 100%,
almost
exclusively in
user mode
ASP.NET Core on
Kestrel
perfsvr 228,062
32 threads, 256
connections
Middleware
class, multi IO
thread
CPU is 100%
Scala - Plain perfsvr 176,509
32 threads,
1024
connections
The actual
TechEmpower
Scala Plain
plaintext app
CPU is 68%,
mostly in kernel
mode
Netty perfsvr 447,993
32 threads, 256
connections
The actual
TechEmpower
Netty app
CPU is 100%
SOURCE: https://github.com/aspnet/benchmarks

13. Summary
 .NET Core 1.0 (renamed from .NET Core 5)
 ASP.NET Core 1.0 (renamed from ASP.NET 5)
 Entity Framework 1.0 (renamed from EF 7)
 .NET Framework 4.6.1
 ASP.NET 4.6
 Entity Framework 6.1.3

14. Resources
 My blog article, https://www.excella.com/insights/demystifying-key-
differences-in-net-core-1-0-vs-net-framework
 The .NET Core CLI documentation on the GitHub site
 NET Docs – Introducing .NET Core
 This excellent blog post from Scott Hanselman about the .NET toolchain
 A blog explaining the rename by Jeffrey T. Fritz
 For more in-depth information on the name and version changes, and on the
components of .NET Core such as the CoreCLR and CLI, watch the NET
Community Standup from January 19th, 2016 where are explained well by
Damian Edwards
 MSDN Magazine – .NET Core – .NET Goes Cross-Platform with .NET Core