diff --git a/core-common/src/main/java/org/glassfish/jersey/ExternalProperties.java b/core-common/src/main/java/org/glassfish/jersey/ExternalProperties.java
index 04ef1bd323..649525cc84 100644
--- a/core-common/src/main/java/org/glassfish/jersey/ExternalProperties.java
+++ b/core-common/src/main/java/org/glassfish/jersey/ExternalProperties.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -37,6 +37,17 @@ public final class ExternalProperties {
      */
     public static final String HTTP_NON_PROXY_HOSTS = "http.nonProxyHosts";
 
+    /**
+     * Property used to indicates if persistent connections should be supported.
+     */
+    public static final String HTTP_KEEPALIVE = "http.keepAlive";
+
+    /**
+     * If HTTP keepalive is enabled this value determines the maximum number
+     * of idle connections that will be simultaneously kept alive, per destination.
+     */
+    public static final String HTTP_MAX_CONNECTIONS = "http.maxConnections";
+
     /**
      * Prevent instantiation.
      */
diff --git a/tests/integration/externalproperties/pom.xml b/tests/integration/externalproperties/pom.xml
index eb56341c26..04ba43c894 100644
--- a/tests/integration/externalproperties/pom.xml
+++ b/tests/integration/externalproperties/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
 
-    Copyright (c) 2020 Oracle and/or its affiliates. All rights reserved.
+    Copyright (c) 2020, 2021 Oracle and/or its affiliates. All rights reserved.
 
     This program and the accompanying materials are made available under the
     terms of the Eclipse Public License v. 2.0, which is available at
@@ -42,6 +42,16 @@
             <artifactId>jersey-test-framework-provider-jetty</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.glassfish.jersey.connectors</groupId>
+            <artifactId>jersey-apache-connector</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish.jersey.connectors</groupId>
+            <artifactId>jersey-jdk-connector</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
diff --git a/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpMaxConnectionTest.java b/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpMaxConnectionTest.java
new file mode 100644
index 0000000000..6186b7e910
--- /dev/null
+++ b/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpMaxConnectionTest.java
@@ -0,0 +1,241 @@
+/*
+ * Copyright (c) 2021 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+
+package org.glassfish.jersey.tests.externalproperties;
+
+import org.glassfish.jersey.ExternalProperties;
+import org.glassfish.jersey.apache.connector.ApacheClientProperties;
+import org.glassfish.jersey.apache.connector.ApacheConnectorProvider;
+import org.glassfish.jersey.client.ClientConfig;
+import org.glassfish.jersey.jdk.connector.JdkConnectorProperties;
+import org.glassfish.jersey.jdk.connector.JdkConnectorProvider;
+import org.glassfish.jersey.server.ResourceConfig;
+import org.glassfish.jersey.test.JerseyTest;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+
+import javax.net.ServerSocketFactory;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.client.Client;
+import javax.ws.rs.client.ClientBuilder;
+import javax.ws.rs.client.InvocationCallback;
+import javax.ws.rs.core.Application;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.SocketException;
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+@RunWith(Parameterized.class)
+public class HttpMaxConnectionTest extends JerseyTest {
+
+    private final Client client;
+
+    @Parameterized.Parameters(name = "{index}: {0}")
+    public static List<Object[]> configurations() {
+        return Arrays.asList(new Object[][]{
+                {createApacheConfig()},
+                {createJdkConfig()},
+        });
+    }
+
+    private static ClientConfig createApacheConfig() {
+        System.setProperty(ExternalProperties.HTTP_MAX_CONNECTIONS, "1");
+        System.setProperty(ExternalProperties.HTTP_KEEPALIVE, "true");
+        ClientConfig config = new ClientConfig();
+        config.connectorProvider(new ApacheConnectorProvider());
+        config.property(ApacheClientProperties.USE_SYSTEM_PROPERTIES, true);
+        return config;
+    }
+
+    private static ClientConfig createJdkConfig() {
+        ClientConfig config = new ClientConfig();
+        config.connectorProvider(new JdkConnectorProvider());
+        config.property(JdkConnectorProperties.MAX_CONNECTIONS_PER_DESTINATION, 1);
+        config.property(JdkConnectorProperties.CONNECTION_IDLE_TIMEOUT, 10_000);
+        return config;
+    }
+
+    public HttpMaxConnectionTest(ClientConfig clientConfigClass) {
+        this.client = ClientBuilder.newClient(clientConfigClass);
+    }
+
+    @Test
+    public void testPersistentConnection() throws IOException, InterruptedException {
+        TestServer testServer = new TestServer(true);
+
+        try {
+            testServer.start();
+            CountDownLatch latch = new CountDownLatch(2);
+            AtomicInteger result1 = new AtomicInteger(-1);
+            sendGetToTestServer(result1, latch);
+            AtomicInteger result2 = new AtomicInteger(-1);
+            sendGetToTestServer(result2, latch);
+
+            assertTrue(latch.await(5, TimeUnit.SECONDS));
+
+            assertEquals(1, result1.get());
+            assertEquals(1, result2.get());
+        } finally {
+            testServer.stop();
+        }
+    }
+
+    @Test
+    public void testNonPersistentConnection() throws IOException, InterruptedException {
+        TestServer testServer = new TestServer(false);
+
+        try {
+            testServer.start();
+            CountDownLatch latch1 = new CountDownLatch(1);
+            AtomicInteger result1 = new AtomicInteger(-1);
+            sendGetToTestServer(result1, latch1);
+            assertTrue(latch1.await(5, TimeUnit.SECONDS));
+            CountDownLatch latch2 = new CountDownLatch(1);
+
+            AtomicInteger result2 = new AtomicInteger(-1);
+            sendGetToTestServer(result2, latch2);
+
+            assertTrue(latch2.await(5, TimeUnit.SECONDS));
+
+            assertEquals(1, result1.get());
+            assertEquals(2, result2.get());
+        } finally {
+            testServer.stop();
+        }
+    }
+
+    private void sendGetToTestServer(final AtomicInteger result, final CountDownLatch latch) {
+        client.target("http://localhost:" + TestServer.PORT).request().async().get(new InvocationCallback<Integer>() {
+            @Override
+            public void completed(Integer response) {
+                System.out.println("#Received: " + response);
+                result.set(response);
+                latch.countDown();
+            }
+
+            @Override
+            public void failed(Throwable throwable) {
+                throwable.printStackTrace();
+            }
+        });
+    }
+
+    @Override
+    protected Application configure() {
+        return new ResourceConfig(EchoResource.class);
+    }
+
+    @Path("/echo")
+    public static class EchoResource {
+
+        @POST
+        public String post(String entity) {
+            return entity;
+        }
+    }
+
+    private static class TestServer {
+
+        static final int PORT = 8321;
+
+        private final boolean persistentConnection;
+        private final ServerSocket serverSocket;
+        private final ExecutorService executorService = Executors.newCachedThreadPool();
+        private final AtomicInteger connectionsCount = new AtomicInteger(0);
+
+        private volatile boolean stopped = false;
+
+        TestServer(boolean persistentConnection) throws IOException {
+            this.persistentConnection = persistentConnection;
+            ServerSocketFactory socketFactory = ServerSocketFactory.getDefault();
+            serverSocket = socketFactory.createServerSocket(PORT);
+        }
+
+        void start() {
+            executorService.execute(() -> {
+                try {
+                    while (!stopped) {
+                        final Socket socket = serverSocket.accept();
+                        connectionsCount.incrementAndGet();
+                        executorService.submit(() -> handleConnection(socket));
+
+                    }
+                } catch (IOException e) {
+                    //do nothing
+                }
+            });
+        }
+
+        private void handleConnection(Socket socket) {
+
+            try {
+                InputStream inputStream = socket.getInputStream();
+                ByteArrayOutputStream receivedMessage = new ByteArrayOutputStream();
+
+                while (!stopped && !socket.isClosed()) {
+                    int result = inputStream.read();
+                    if (result == -1) {
+                        return;
+                    }
+
+                    receivedMessage.write((byte) result);
+                    String msg = new String(receivedMessage.toByteArray(), "ASCII");
+                    if (msg.contains("\r\n\r\n")) {
+                        receivedMessage = new ByteArrayOutputStream();
+                        OutputStream outputStream = socket.getOutputStream();
+                        String response = "HTTP/1.1 200 OK\r\nContent-Length: 1\r\nContent-Type: text/plain\r\n";
+                        if (!persistentConnection) {
+                            response += "Connection: Close\r\n";
+                        }
+                        response += "\r\n" + connectionsCount.get();
+                        outputStream.write(response.getBytes("ASCII"));
+                        outputStream.flush();
+                    }
+                }
+            } catch (IOException e) {
+                if (!e.getClass().equals(SocketException.class)) {
+                    e.printStackTrace();
+                }
+            } finally {
+                try {
+                    socket.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        void stop() throws IOException {
+            executorService.shutdown();
+            serverSocket.close();
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpProxyTest.java b/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpProxyTest.java
index 94100297f0..e71cafadb7 100644
--- a/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpProxyTest.java
+++ b/tests/integration/externalproperties/src/test/java/org/glassfish/jersey/tests/externalproperties/HttpProxyTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -22,6 +22,7 @@
 import org.glassfish.jersey.ExternalProperties;
 import org.glassfish.jersey.server.ResourceConfig;
 import org.glassfish.jersey.test.JerseyTest;
+import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
@@ -38,6 +39,7 @@ public class HttpProxyTest extends JerseyTest {
     private static final String PROXY_HOST = "localhost";
     private static final String PROXY_PORT = "9997";
     private static boolean proxyHit = false;
+    private Server server;
 
     @Path("resource")
     public static class ProxyTestResource {
@@ -58,7 +60,7 @@ protected Application configure() {
     public void startFakeProxy() {
         System.setProperty(ExternalProperties.HTTP_PROXY_HOST, PROXY_HOST);
         System.setProperty(ExternalProperties.HTTP_PROXY_PORT, PROXY_PORT);
-        Server server = new Server(Integer.parseInt(PROXY_PORT));
+        server = new Server(Integer.parseInt(PROXY_PORT));
         server.setHandler(new ProxyHandler(false));
         try {
             server.start();
@@ -67,6 +69,11 @@ public void startFakeProxy() {
         }
     }
 
+    @After
+    public void stopFakeProxy() throws Exception {
+        server.stop();
+    }
+
     @Test
     public void testProxy() {
         System.setProperty(ExternalProperties.HTTP_NON_PROXY_HOSTS, "");