anchor.diff:  
   Refer to the [HM9000 readme](https://github.com/cloudfoundry/hm9000) for more information about the HM9000 architecture.
   
  -## Application Execution (DEA)
  +## <a id="dea"></a> Application Execution (DEA) ##
   
   The [Droplet Execution Agent](./execution-agent.html) manages application
   instances, tracks started instances, and broadcasts state messages.
  
positive.code: * Buildpacks
  * Droplets
  
  ## Service Brokers
  
  Applications typically depend on [services](../../services/) such as databases or
  third-party SaaS providers.
  When a developer provisions and binds a service to an application, the service
  broker for that service is responsible for providing the service instance.
  
  ## Message Bus
  
  Cloud Foundry uses [NATS](./messaging-nats.html), a lightweight
  publish-subscribe and distributed queueing messaging system, for internal
  communication between components.
  
  ## Logging and Statistics
  
  The metrics collector gather metrics from the components.
  Operators can use this information to monitor an instance of Cloud Foundry.
  
negative.code: 
  ![Cloud Foundry Architecture](/images/cf_architecture_block.png)
  
  ## <a id="router"></a>Router ##
  
  The [router](./router.html) routes incoming traffic to the appropriate
  component, usually the Cloud Controller or a running application on a DEA node.
  
  ## <a id="uaa"></a> Authentication ##
  
  The OAuth2 server (the [UAA](./uaa.html)) and Login Server work together to
  provide identity management.
  
  ## <a id="cc"></a> Cloud Controller ##
  
  The [Cloud Controller](./cloud-controller.html) is responsible for managing the
  lifecycle of applications.
  