code: public static ProbeSender createMulticastProbeSender(String niName) throws TransportConfigException {
      Transport mcastTransport = new MulticastTransport(niName);
      ProbeSender gen = new ProbeSender(mcastTransport);
      return gen;
    }
docs: Create a Multicast ProbeSender specifying the Network Interface to send
  on.
  
  @param niName network interface name
  @return configured ProbeSender instance
  @throws TransportConfigException if something went wrong