# Package org.apache.storm.networktopography

- Interface Summary
  Interface | Description
  --- | ---
  DNSToSwitchMapping | An interface that must be implemented to allow pluggable DNS-name/IP-address to RackID resolvers.

- Class Summary
  Class | Description
  --- | ---
  AbstractDNSToSwitchMapping | This is a base class for DNS to Switch mappings.
  DefaultRackDNSToSwitchMapping | This class implements the `DNSToSwitchMapping` interface It returns the DEFAULT_RACK for every host.