public static void createConcurrentSender(String dsName, int remoteDsId, boolean isParallel,
      Integer maxMemory, Integer batchSize, boolean isConflation, boolean isPersistent,
      GatewayEventFilter filter, boolean isManualStart, int concurrencyLevel, OrderPolicy policy) {

    File persistentDirectory =
        new File(dsName + "_disk_" + System.currentTimeMillis() + "_" + VM.getCurrentVMNum());
    persistentDirectory.mkdir();
    DiskStoreFactory dsf = cache.createDiskStoreFactory();
    File[] dirs1 = new File[] {persistentDirectory};
    GatewaySenderFactory gateway = configureGateway(dsf, dirs1, dsName, isParallel, maxMemory,
        batchSize, isConflation, isPersistent, filter, isManualStart, concurrencyLevel, policy,
        GatewaySender.DEFAULT_SOCKET_BUFFER_SIZE);
    gateway.create(dsName, remoteDsId);
  }
Returns a Map that contains the count for number of cache server and number of Receivers.
geode-wan/src/distributedTest/java/org/apache/geode/internal/cache/wan/WANTestBase.java