Dropsonde is a go library that allows the CF components using it to emit logs and metrics. The current flow for CF components is to emit their logs and metrics to their local metron agent which then forwards them to the Doppler servers in Loggregator. The metron agents only listen on the local interface and immediately signs the messages before sending them off to the Dopplers. So for now, the destination parameter for dropsonde will always point to the local metron agent.

Here is some more info on Metron https://github.com/cloudfoundry/loggregator/tree/develop/src/metron
Here is some more info on Dropsonde https://github.com/cloudfoundry/dropsonde