Understanding Landscape Descriptions – Part I: the Simple Approach to Explaining Products, Product Instances, and Software Components
Descriptions – or “modeling” – of system landscapes are based on some entities called Products, Product Instances, and Software Components. These terms and the model entities they describe, turn up in SAP’s management and development systems. What may be even more important for you is that they are the basis for the description of landscapes in the SAP Solution Manager, which you need, for example, when it comes to system monitoring or maintenance, especially.
Understanding these instances therefore is necessary for successful management of these landscapes. This blog series is meant to explain these terms.
Products and Their Elements
Let’s start with a very simple example not from the software world, but something more tangible – let’s take a car…
Figure 1: A car as a product and its building elements mapped to SAPs product model.
Here is how you can map SAP’s term to the car (of course a car – as SAP’s products – has much more parts):
- Product: A product is the model of a car in different versions and including the Vehicle Title (your contract for using the product) Certificate of Guarantee (the maintenance contract). So a product is what you buy.
- Software Components (SCs): Software Components are the elements that are developed as one piece, and what you would usually see as one part – the coach, the windows, and the wheels. There are optional components, such as Add-Ons, such as transport cases, antenna, spare wheel…
- Product Instances: Software Components may be seen and handled one by one, but when it comes to setting up a product, some pieces simply belong together: A set of windows belongs to just one coach type, front and rear wheel are a matching set. Such sets of Software Components, which belong together, are the Product Instances.
Here are some points you should know about Product Instances: They
- can be reused in several Products – see the wheel set, for example
- can contain one or many SCs
- can be optional – again, see the Add-On
- Usage: What you use in the end is a specific configuration of a certain product.
Product’s Elements – Their Purpose
So what is the purpose of the elements described above?
Products define an overall scope, a set of functions solving a business need. It would not help to think in Software Components when business processes overall are the topic. That also is important, when it comes to maintenance of an IT landscape: Business processes, and hence the products are what you need to see as the units of an upgrade.
Software Components are the units that are developed, but as discussed, from an installation or update perspective, only certain sets of SCs make sense – so in the installation and even more in the case of system maintenance, you’ll deal with these sets, called Product Instances.
Next Steps in Understanding
Installing products will bring them into existence. The similarities with the tangible car will fade a bit, but you will definitively need the terms explained here when it comes to maintenance of your systems. So we will continue this series describing the details of Products and Product Instances, and how systems are defined running the elements.
- You’ll find the blog series and links to tools and application dealing with them on a Landscape Descriptions