diff --git a/dnet-ariadneplus/src/main/java/eu/dnetlib/ariadneplus/workflows/nodes/IndexOnESJobNode.java b/dnet-ariadneplus/src/main/java/eu/dnetlib/ariadneplus/workflows/nodes/IndexOnESJobNode.java
index 381a411..a4b9e4d 100644
--- a/dnet-ariadneplus/src/main/java/eu/dnetlib/ariadneplus/workflows/nodes/IndexOnESJobNode.java
+++ b/dnet-ariadneplus/src/main/java/eu/dnetlib/ariadneplus/workflows/nodes/IndexOnESJobNode.java
@@ -1,32 +1,22 @@
 package eu.dnetlib.ariadneplus.workflows.nodes;
 
 import com.google.common.collect.Lists;
-import com.google.gson.Gson;
-import eu.dnetlib.enabling.resultset.ResultSetInfo;
-import eu.dnetlib.enabling.resultset.client.ResultSetClient;
 import eu.dnetlib.msro.workflows.graph.Arc;
 import eu.dnetlib.msro.workflows.nodes.AsyncJobNode;
-import eu.dnetlib.msro.workflows.nodes.SimpleJobNode;
 import eu.dnetlib.msro.workflows.procs.Env;
-import eu.dnetlib.msro.workflows.procs.Token;
-import eu.dnetlib.msro.workflows.util.ResultsetProgressProvider;
 import eu.dnetlib.msro.workflows.util.WorkflowsConstants;
-import eu.dnetlib.rmi.common.ResultSet;
 import eu.dnetlib.rmi.manager.MSROException;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.http.NameValuePair;
-import org.apache.http.client.HttpClient;
 import org.apache.http.client.entity.UrlEncodedFormEntity;
 import org.apache.http.client.methods.CloseableHttpResponse;
 import org.apache.http.client.methods.HttpPost;
-import org.apache.http.entity.StringEntity;
+import org.apache.http.config.SocketConfig;
 import org.apache.http.impl.client.CloseableHttpClient;
-import org.apache.http.impl.client.HttpClients;
-import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
+import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.message.BasicNameValuePair;
-import org.springframework.beans.factory.annotation.Autowired;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -34,7 +24,7 @@ import java.net.ConnectException;
 import java.util.List;
 
 
-public class IndexOnESJobNode extends SimpleJobNode {
+public class IndexOnESJobNode extends AsyncJobNode {
 
 	private static final Log log = LogFactory.getLog(IndexOnESJobNode.class);
 
@@ -42,20 +32,15 @@ public class IndexOnESJobNode extends SimpleJobNode {
 	private String datasourceInterface;
 	private String datasource;
 
-	//for parallel requests to the publisher endpoint
-//	private int nThreads = 5;
-
 	@Override
 	protected String execute(final Env env) throws Exception {
 
 		int statusCode = -1;
 		String indexOnESResult = "noResult";
 		log.info("Publisher endpoint: " + getPublisherEndpoint());
-//		PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
-//		cm.setMaxTotal(nThreads);
-//		CloseableHttpClient client = HttpClients.custom().setConnectionManager(cm).build();
-		CloseableHttpClient client = HttpClients.createDefault();
-
+		SocketConfig socketConfig = SocketConfig.custom().setSoKeepAlive(true).build();
+		CloseableHttpClient client = HttpClientBuilder.create()
+				.setDefaultSocketConfig(socketConfig).build();
 		log.info("IndexOnES endpoint: " + getIndexOnESEndpoint());
 		CloseableHttpResponse responsePOST = null;
 		try {
@@ -73,7 +58,9 @@ public class IndexOnESJobNode extends SimpleJobNode {
 			statusCode = responsePOST.getStatusLine().getStatusCode();
 			try(InputStream responseBody = responsePOST.getEntity().getContent()) {
 				indexOnESResult = IOUtils.toString(responseBody, "UTF-8");
-			} catch (Exception e) {}
+			} catch (Exception e) {
+				log.error(e);
+			}
 			switch (statusCode) {
 			case 200:
 				log.info("index on ES completed");