Welcome!

Microservices Expo Authors: Elizabeth White, Pat Romanski, Reinhard Brandstädter, Liz McMillan, Cynthia Dunlop

Related Topics: Microsoft Cloud

Microsoft Cloud: Article

The Myth of .NET Purity

The Myth of .NET Purity

There is an increasing amount of discussion around the topic of ".NET Purity" in development circles. When selling an application the question often arises "is your application 100% .NET?" or "How much of your application is .NET?" There is an implied qualitative judgment behind these questions and it's usually pejorative.

The implication is that an application that is entirely written in .NET, presumably without any interoperation with COM or direct calls to the Win32 API, is superior to an application that is a combination of technologies.

Certainly .NET represents a fantastic leap in developer productivity and puts a clean, consistent face on the services that the Windows Platform provides. For many years the set of interfaces provided by the Windows OS Platform - collectively known as the Windows SDK - have been exposed to developers as exported "C"-style functions in DLLs, and in recent years, via the Component Object Model (COM).

Common Language Runtime or Virtual Machine?
Often the .NET Common Language Runtime, or CLR, is directly compared to the Java Virtual Machine. Initially, there are many clear parallels: both are "managed" environments that provide a component container, both consume a "partially chewed" intermediate language, both provide low-level services like garbage collection and threading conveniences.

While these parallels are superficially compelling, these two implementations differ fundamentally in philosophy. Comparing the CLR to the VM is reasonable only to a certain point - their architectural goals are ultimately different.

Sun promotes a marketing program called 100% Pure Java, which is certainly appropriate if code portability and underlying operating system transparency is a desirable endpoint. However, many 3rd party Java Application Servers create a competitive advantage by judicious use of "C" function calls directly down (via Java Native Interface or JNI) into their host Operating Systems value-added services that are not exposed by the Java Application Platform (the Java Class Library). Calling into the core platform is the only way to make use of base functionality that is only presented via a native interface!

The Java VM is truly a "virtual machine" that's ultimate goal is to abstract (virtualize) away the underlying Operating System and provide an idealized (not necessarily ideal, but idealized) environment for development. The Java Virtual machine is also intimately united with the API - the Java Application Platform, which services provided by the VM implementation. Regardless of where you run your compiled Java code, you will run within the context of the Virtual Machine and ostensibly link with supplied Java Platform APIs.

The .NET Common Language Runtime is named well as it is used more as a Language Runtime than a Virtual Machine. While it successfully abstracts away aspects of underlying hardware through its use of an Intermediate Language, when the CLR is combined with the .NET Framework Library of APIs it is married to the underlying platform, which is Windows. The CLR provides all the facilities of the Windows Platform to any .NET-enabled Language.

.NET Framework Library
The Windows Platform has dozens and dozens of high-level system services that are exposed by thousands of APIs. This large library of functionality encompasses various levels of richness. A low-level API may open a file off a disk, while a high-level one might play an audio file. The designers of the .NET Framework wanted to create a consistent object-oriented face on a rich legacy of platform functionality. The CLR and .NET Framework work together to expose the capabilities within the Windows Platform, including those that may have previously been hidden away in difficult or little known APIs.

While the CLR provides a new paradigm for application development, it does not close the door on existing libraries. The CLR provides interop services to the developer but the biggest consumer of these services are the .NET Class Libraries that unlock existing Windows Platform abilities via a .NET API!

For example, when sending email using the .NET Framework Library class System.Web.Mail.SmtpMail, the Class Library uses a helper class that abstracts the existing CDO (Collaboration Data Objects) COM Library. This is just one example where a .NET Library developer chose to rely on a production-ready reliable existing library rather than write something from scratch. This example and dozens of others with the Library not withstanding, the Common Language Runtime still at some point needs to work with the Windows internal APIs.

If Microsoft were to truly virtualize the machine, they would have marginalized their investment in the Windows platform. Certainly it behooved the designers to make transitions to existing libraries as painless as possible. They have enabled this with NET » COM Interop via both Runtime- and COM-Callable Wrappers, the ability to tap into standard Win32 Platform APIs via a technology called P/Invoke (short for Platform Invoke) as well as other options. When writing code that is hosted in the CLR the vast resources of platform are just sitting under the developer - the runtime is transparent rather than virtual! This marks a fundamentally different view of the platform that other virtualizing machine implementations.

While creating a new fresh application using only .NET may offer some benefits in the arenas of deployment or marketing, these benefits may be not realized when weighed against the cost of rewriting non-.NET components in .NET when those legacy components could have been leveraged. A "pure" .NET solution can only make use of either those pieces of functionality that can be achieve entirely within the runtime, or those functions that have been exposed by the Base Class Library - which itself uses COM Interop and P/Invoke!

The .NET Framework Library itself isn't "pure .NET" as it takes every opportunity to take full advantage of the underlying platform primitives. Moreover, the concept of .NET Purity is rendered specious in this new light. The .NET Framework is the best way to create business components on the Windows Platform, but any applications along with the .NET Framework are only lifted as high as the underlying Windows OS services.

"Hybrid" Solutions provide Real Solutions
Many large existing applications are written in Visual C++ and COM. They are written "close to the metal" to take full advantage of native Windows multi-threading and fine-grained memory management. However, new business components may also be written in a .NET language such as C# or VB.NET. The existing system then hosts the .NET Common Language Runtime within its process space and Interops. The interface is usually COM interop but only incurs minimal overhead of between 10 and 40 processor instructions per in-proc call.

.NET Components hosted with in the legacy applicaiton can take advantage of that application's existing services. Lower level developer features such as memory management, object lifetime and object orientation are provided by the CLR, while higher level vertical-specific business functionality is exposed via the legacy application.

This "hybrid" can provide a best-of-breed solution on the Windows Platform exploiting both the highly performant low-level APIs via C++ and the highly componentized and object oriented features of the .NET Framework. These solutions can work very successfully while companies migrate their existing code bases to the .NET Framework.

More Stories By Scott Hanselman

Scott Hanselman will be starting a new job at Microsoft as a senior program manager in the developer division. His blog is at http://www.hanselman.com.

Comments (4) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
Tim Huckaby 07/25/03 07:07:00 PM EDT

Your comments on system.directory are interesting. Adsi is simply a com wrapper, so technically it?s a ?wrapped wrapper? of the native ldap api which, of course, is c++ only. Being that said, the directory entry class you are referring to is a ?wrapped, wrapped wrapper?. Ultimately, the big disappointment of the .net framework 1.1 and the hope for 2.0 is more native framework classes.

Derek Ferguson 07/18/03 10:12:00 AM EDT

I would never suggest that COM Interop should be gotten rid of or is in any way, shape, or form "evil." However, as a developer who spends more than 90% of my coding time working with the System.DirectoryServices and System.Management namespaces, let me tell you -- MS could have save developers a lot of gried by having written some managed protocol handlers here, rather than just wrapping up the old, troubled API's.

As one example of this, the DirectoryEntry class in System.DirectoryServices allows you to pass a username and password to its constructor. However, when you use the WinNT ADSI provider, these parameters are sometimes ignored. Why is this? Because of a limitation in the existing API's that were wrapped!

Similar problems abound in the System.Management namespace -- where I recently managed to prove that Impersonation (a native API) interacts differently with EnablePrivilieges (a wrapped API) under ASP.NET than it does under the Console. In working through this with MS, I have been passed around to 10 different people in their Support infrastructure. Why? Because the old, obscure API's that have been wrapped are a "dark art" that are only known by a few individuals within the Redmond infrastructure.

Once again: it would've been better to have recreated the whole thing in C#.

Dean Guida 07/25/03 04:00:00 PM EDT

There is a lot to be said for purity for purity's sake. I have never subscribed to this type of thinking. At the end of the day we all want to build dependable software that solves the business problem at hand. Everything should always be taking in context of a solution with a sense of practicality. I think most of the software development community has this maturity.

Patrick Hynds 07/17/03 10:16:00 PM EDT

I think this article is right on, but felt that we should confront the issue of why this kind of rebuttal is needed (and it is needed). We find people who are earnest only in so far as they can justify their existence. Therefore they brand something heresy as soon as they abandon the practice themselves. Lets assume that COM interop was a horrible waste of resource, it still wouldn't justify discarding a tool and the wealth of existing functionality the last generation always holds in such a wholesale manner. I have seen people in ASP circles a while back declare that "Session State is bad". Like hybrid applications Session State in ASP is a tool, use it, don't use it, but if you happen to need a hammer it doesn't make the saw evil.

@MicroservicesExpo Stories
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, wh...
IoT generates lots of temporal data. But how do you unlock its value? How do you coordinate the diverse moving parts that must come together when developing your IoT product? What are the key challenges addressed by Data as a Service? How does cloud computing underlie and connect the notions of Digital and DevOps What is the impact of the API economy? What is the business imperative for Cognitive Computing? Get all these questions and hundreds more like them answered at the 18th Cloud Expo...
Cloud-based NCLC (No-code/low code) application builder platforms empower everyone in the organization to quickly build applications and executable processes that broaden access, deepen collaboration, and enhance transparency for all team members. Line of business owners (LOBO) and operations managers know best their part of the business and their processes. IT departments are beginning to leverage NCLC platforms to empower and enable LOBOs to lead the innovation, transform the organization, an...
@DevOpsSummit taking place June 7-9, 2016 at Javits Center, New York City, and Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 18th International @CloudExpo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world.
SYS-CON Events announced today the Docker Meets Kubernetes – Intro into the Kubernetes World, being held June 9, 2016, in conjunction with 18th Cloud Expo | @ThingsExpo, at the Javits Center in New York, NY. Register for 'Docker Meets Kubernetes Workshop' Here! This workshop led by Sebastian Scheele, co-founder of Loodse, introduces participants to Kubernetes (container orchestration). Through a combination of instructor-led presentations, demonstrations, and hands-on labs, participants learn ...
Just last week a senior Hybris consultant shared the story of a customer engagement on which he was working. This customer had problems, serious problems. We’re talking about response times far beyond the most liberal acceptable standard. They were unable to solve the issue in their eCommerce platform – specifically Hybris. Although the eCommerce project was delivered by a system integrator / implementation partner, the vendor still gets involved when things go really wrong. After all, the vendo...
The initial debate is over: Any enterprise with a serious commitment to IT is migrating to the cloud. But things are not so simple. There is a complex mix of on-premises, colocated, and public-cloud deployments. In this power panel at 18th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists will look at the present state of cloud from the C-level view, and how great companies and rock star executives can use cloud computing to meet their most ambitious and disruptive business ...
Agile teams report the lowest rate of measuring non-functional requirements. What does this mean for the evolution of quality in this era of Continuous Everything? To explore how the rise of SDLC acceleration trends such as Agile, DevOps, and Continuous Delivery are impacting software quality, Parasoft conducted a survey about measuring and monitoring non-functional requirements (NFRs). Here's a glimpse at what we discovered and what it means for the evolution of quality in this era of Continuo...
You might already know them from theagileadmin.com, but let me introduce you to two of the leading minds in the Rugged DevOps movement: James Wickett and Ernest Mueller. Both James and Ernest are active leaders in the DevOps space, in addition to helping organize events such as DevOpsDays Austinand LASCON. Our conversation covered a lot of bases from the founding of Rugged DevOps to aligning organizational silos to lessons learned from W. Edwards Demings.
When I talk about driving innovation with self-organizing teams, I emphasize that such self-organization includes expecting the participants to organize their own teams, give themselves their own goals, and determine for themselves how to measure their success. In contrast, the definition of skunkworks points out that members of such teams are “usually specially selected.” Good thing he added the word usually – because specially selecting such teams throws a wrench in the entire works, limiting...
As AT&Ts VP of Domain 2.0 architecture writes one aspect of their Domain 2.0 strategy is a goal to embrace a Microservices Application Architecture. One page 9 they describe how these envisage them fitting into the ECOMP architecture: "The initial steps of the recipes include a homing and placement task using constraints specified in the requests. ‘Homing and Placement' are micro-services involving orchestration, inventory, and controllers responsible for infrastructure, network, and applicati...
Many banks and financial institutions are experimenting with containers in development environments, but when will they move into production? Containers are seen as the key to achieving the ultimate in information technology flexibility and agility. Containers work on both public and private clouds, and make it easy to build and deploy applications. The challenge for regulated industries is the cost and complexity of container security compliance. VM security compliance is already challenging, ...
Application development and delivery methods have undergone radical changes in recent years to improve scalability and resiliency. Container images are the new build and deployment artifacts that are used to ship and run software. While startups have long been comfortable experimenting with and embracing new technologies, even large enterprises are now re-architecting their software systems so that they can benefit from container-enabled micro services architectures. With the launch of DC/OS, w...
SYS-CON Events announced today TechTarget has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. TechTarget is the Web’s leading destination for serious technology buyers researching and making enterprise technology decisions. Its extensive global networ...
Earlier this week, we hosted a Continuous Discussion (#c9d9) on Continuous Delivery (CD) automation and orchestration, featuring expert panelists Dondee Tan, Test Architect at Alaska Air, Taco Bakker, a LEAN Six Sigma black belt focusing on CD, and our own Sam Fell and Anders Wallgren. During this episode, we discussed the differences between CD automation and orchestration, their challenges with setting up CD pipelines and some of the common chokepoints, as well as some best practices and tips...
Korean Broadcasting System (KBS) will feature the upcoming 18th Cloud Expo | @ThingsExpo in a New York news documentary about the "New IT for the Future." The documentary will cover how big companies are transmitting or adopting the new IT for the future and will be filmed on the expo floor between June 7-June 9, 2016, at the Javits Center in New York City, New York. KBS has long been a leader in the development of the broadcasting culture of Korea. As the key public service broadcaster of Korea...
Automation is a critical component of DevOps and Continuous Delivery. This morning on #c9d9 we discussed CD Automation and how you can apply Automation to accelerate release cycles, improve quality, safety and governance? What is the difference between Automation and Orchestration? Where should you begin your journey to introduce both?
While there has been much ado about interoperability, there are still no real solutions, same as last year and the year before that. The large EHR vendors who continue to dominate the market still maintain that interoperability is all but solved, still can't connect EHRs across the continuum causing frustration by providers and a disservice to patients. The ONC pays lip service to the problem, but that is about it. It is time for the healthcare industry to consider alternatives like middleware w...
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York and Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty ...
Our CTO, Anders Wallgren, recently sat down to take part in the “B2B Nation: IT” podcast — the series dedicated to serving the IT professional community with expert opinions and advice on the world of information technology. Listen to the great conversation, where Anders shares his thoughts on DevOps lessons from large enterprises, the growth of microservices and containers, and more.