anchor.diff:  
   
   <%# Reset page title based on product title %>
  -<% current_page.data.title = vars.product_short + " Overview" if vars.platform_code != 'CF'  %>
  +<% current_page.data.title = vars.product_short + " Overview" if vars.platform_code != 'CF' %>
   
   <% if vars.platform_code == 'CF' %>
   
  
positive.code: 
  Cloud Foundry generates system logs from Cloud Foundry components and app logs from hosted apps
  
  As Cloud Foundry runs, its component and host VMs generate logs and metrics. Cloud Foundry apps also typically generate logs. The <%=vars.loggregator_name_or_link%> system aggregates the component metrics and app logs into a structured, usable form, the _Firehose_. You can use all of the output of the Firehose, or direct the output to specific uses, such as monitoring system internals, triggering alerts, or analyzing user behavior, by applying _nozzles_.
  
  The component logs follow a different path. They stream from rsyslog agents, and the cloud operator can configure them to stream out to a syslog drain.
  
  ### <a id='services'></a> Using Services with Cloud Foundry
  
  Typical apps depend on free or metered <%=vars.services_link%> such as databases or third-party APIs. To incorporate these into an app, a developer writes a Service Broker, an API that publishes to the Cloud Controller the ability to list service offerings, provision the service, and enable apps to make calls out to it.
  
  [//]: # (Comment: Below calls vars concept_product_* in book repository template_vars.yml.)
  [//]: # ( The vars *_text and *_image hold locations of partial and image files.    )
  
negative.code: 
  <% end %>
  
  ## <a id='overview'></a>Overview
  
  Cloud platforms let anyone deploy network apps or services and make them available to the world in a few minutes. When an app becomes popular, the cloud easily scales it to handle more traffic, replacing with a few keystrokes the build-out and migration efforts that once took months. Cloud platforms represent the next step in the evolution of IT, enabling you to focus exclusively on your apps and data without worrying about underlying infrastructure.
  
  ![At the top left of the image is a column with the header 'Traditional IT', below which are nine black boxes labeled 'Applications', 'Data', 'Runtime', 'Middleware', 'O/S', 'Virtualization', 'Servers', 'Storage', and 'Networking'. A vertical line runs along the left side of the nine boxes and is labeled 'You Manage'. At the top center of the image is a column with the header 'IaaS', below which are four black boxes labeled 'Applications', 'Data', 'Runtime', and 'Middleware', followed by five white boxes labeled 'O/S', 'Virtualization', 'Servers', 'Storage', and 'Networking'. A vertical line runs along the left side the four black boxes and is labeled 'You Manage'. A vertical line runs along the right side of the five white boxes and is labeled 'IaaS Provider'. At the top right of the image is a column with the header 'Platform', below which are two black boxes labeled 'Applications' and 'Data', followed by seven white boxes labeled 'Runtime', 'Middleware', 'O/S', 'Virtualization', 'Servers', 'Storage', and 'Networking'. A vertical line runs along the left side the two black boxes and is labeled 'You Manage'. A vertical line runs along the right side of the seven white boxes and is labeled 'Cloud Foundry on IaaS'. At the bottom left of the image is a vertical blue dashed line that is labeled 'Agility and Cost Savings' with an arrow that points to the top of the image. Also at the bottom left of the image is a horizontal blue dashed line that is labeled 'Cloud Enablement' with an arrow that points to the bottom right of the image. At the bottom of the image is the text 'IaaS=Infrastructure as a Service (AWS, vSphere, OpenStack, etc.)'.](images/power-of-platform.png)
  
  Not all cloud platforms are created equal. Some have limited language and framework support, lack key app services, or restrict deployment to a single cloud. Cloud Foundry has become the industry standard. It is an [open source](https://github.com/cloudfoundry) platform that you can deploy to run your apps on your own computing infrastructure, or deploy on an IaaS like AWS, vSphere, or OpenStack. You can also use a PaaS deployed by a commercial [Cloud Foundry cloud provider](https://www.cloudfoundry.org/learn/certified-providers/). A broad [community](https://www.cloudfoundry.org/community/) contributes to and supports Cloud Foundry. The platform's openness and extensibility prevent its users from being locked into a single framework, set of app services, or cloud.
  
  