Service applications provide specific functionality to users in SharePoint 2013. This includes access to application functionality with Microsoft Excel 2013, Microsoft Visio 2013, and supporting services such as the Managed Metadata Service or the Business Connectivity Services. In addition, there are underlying service applications that provide functionality across SharePoint 2013, such as the Application Discovery and Load Balancer Service Application and the State Service. These are not configurable from the service application listing on the Manage Service Applications page. The framework of the service application architecture in SharePoint 2013 is designed to enable architects to select only the services that are required to deliver a business solution.
- A service application has the following components:
- An administrative interface, through which you can manage the associated service application
- An application pool
- A service application proxy group
- A service database or databases, dependent on the requirements of the service
- One or more physical instances-the service process running on a physical server
For a service application to talk to a specific web application, it must use a service application connection. When you deploy a service application, you create a service application connection, which is more commonly known as a proxy. The proxy manages the connection information so that the service application can communicate with service requests from service consumers, such as Web Parts. You can link and manage service applications against individual web applications. This means that you have the flexibility to deploy multiple service application instances, which you can isolate to match performance or security requirements. You should remember that by default, service applications are associated with all of the web applications on a farm, so you have to specifically associate service applications to web applications if you don’t want the default settings. A service application proxy is created automatically when you create a new service application. You can group multiple proxies together, which is then referred to as a service application connection group, or proxy group. By default, SharePoint creates a single proxy group called default. You can create additional proxy groups to re-associate service applications to web applications if needed. The majority of service applications have one or more associated databases. The system-generated names for these databases are not easy to relate to the service application. For easier management and recognition, you should define your own database names for your service application databases. You should be aware of the potential size to which these databases can grow. The service application architecture runs across the SharePoint 2013 and SharePoint Online SKUs, although not all SKUs offer all of the SharePoint services. The service application architecture is also extensible, so third-party vendors can develop service applications that you can deploy in your solution. The flexibility of the service application architecture—where you can deploy multiple instances of the same service—provides a range of design options for SharePoint 2013 architects. You can implement multiple instances of a service application for resilience, performance, or security.