Test-VOLTHA:
    Added test scenarios considering VOLTHA and dhcp relay.
    ISC dhcp server will be running in cord tester.

Change-Id: I5040a386a0618738b4dff6b9b53373a05ca127d3
diff --git a/src/test/voltha/volthaTest.py b/src/test/voltha/volthaTest.py
index 2578521..526f593 100644
--- a/src/test/voltha/volthaTest.py
+++ b/src/test/voltha/volthaTest.py
@@ -249,3 +249,611 @@
         6  Verify that subscriber should not get ip from dhcp server, ping to gateway.
         """
 
+def test_subscriber_with_voltha_for_dhcp_starvation_positive_scenario(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Repeat step 3 and 4 for 10 times.
+        6  Verify that subscriber should get ip from dhcp server.
+        """
+
+    def test_subscriber_with_voltha_for_dhcp_starvation_negative_scenario(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber without of pool ip to dhcp server which is running as onos app.
+        4. Verify that subscriber should not get ip from dhcp server.
+        5. Repeat steps 3 and 4 for 10 times.
+        6  Verify that subscriber should not get ip from dhcp server.
+        """
+    def test_subscriber_with_voltha_for_dhcp_sending_multiple_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Repeat step 3 for 50 times.
+        6  Verify that subscriber should get same ip which was received from 1st discover from dhcp server.
+        """
+    def test_subscriber_with_voltha_for_dhcp_sending_multiple_request(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Send DHCP request to dhcp server which is running as onos app.
+        6. Repeat step 5 for 50 times.
+        7. Verify that subscriber should get same ip which was received from 1st discover from dhcp server.
+        """
+
+    def test_subscriber_with_voltha_for_dhcp_requesting_desired_ip_address(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired ip address from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip which was requested in step 3 from dhcp server successfully.
+        """
+
+    def test_subscriber_with_voltha_for_dhcp_requesting_desired_out_pool_ip_address(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired out of pool ip address from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber should not get ip which was requested in step 3 from dhcp server, and its offered only within dhcp pool of ip.
+        """
+    def test_subscriber_with_voltha_for_dhcp_deactivate_dhcp_app_in_onos(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Deactivate dhcp server app in onos.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from dhcp server, and ping to gateway.
+        """
+    def test_subscriber_with_voltha_for_dhcp_renew_time(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Send dhcp renew packet to dhcp server which is running as onos app.
+        6. Repeat step 4.
+        """
+    def test_subscriber_with_voltha_for_dhcp_rebind_time(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Send dhcp rebind packet to dhcp server which is running as onos app.
+        6. Repeat step 4.
+        """
+    def test_subscriber_with_voltha_for_dhcp_disable_olt_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Disable olt devices which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from dhcp server, and ping to gateway.
+        """
+    def test_subscriber_with_voltha_for_dhcp_disable_enable_olt_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Disable olt devices which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from dhcp server, and ping to gateway.
+        8. Enable olt devices which is being detected in voltha CLI.
+        9. Repeat steps 3 and 4.
+        """
+    def test_subscriber_with_voltha_for_dhcp_disable_onu_port_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Disable onu port which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from dhcp server, and ping to gateway.
+        """
+    def test_subscriber_with_voltha_for_dhcp_disable_enable_onu_port_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscriber get ip from dhcp server successfully.
+        5. Disable onu port which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from dhcp server, and ping to gateway.
+        8. Enable onu port which is being detected in voltha CLI.
+        9. Repeat steps 3 and 4.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcp_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got different ips from dhcp server successfully.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcp_multiple_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Repeat step 3 and 4 for 10 times for both subscribers.
+        6  Verify that subscribers should get same ips which are offered the first time from dhcp server.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_multiple_discover_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Repeat step 3 and 4 for 10 times for only one subscriber and ping to gateway from other subscriber.
+        6  Verify that subscriber should get same ip which is offered the first time from dhcp server and other subscriber ping to gateway should not failed
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_discover_desired_ip_address_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from one residential subscriber to dhcp server which is running as onos app.
+        3. Send dhcp request with desired ip from other residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscribers had got different ips (one subscriber desired ip and other subscriber random ip) from dhcp server successfully.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_discover_within_and_wothout_dhcp_pool_ip_addresses(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired wihtin dhcp pool ip from one residential subscriber to dhcp server which is running as onos app.
+        3. Send dhcp request with desired without in dhcp pool ip from other residential subscriber to dhcp server which is running as onos app.
+        4. Verify that subscribers had got different ips (both subscriber got random ips within dhcp pool) from dhcp server successfully.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_disable_onu_port_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Disable onu port on which access one subscriber and ping to gateway from other subscriber.
+        6. Repeat step 3 and 4 for one subscriber where uni port is down.
+        7. Verify that subscriber should not get ip from dhcp server and other subscriber ping to gateway should not failed.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_disable_enable_onu_port_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Disable onu port on which access one subscriber and ping to gateway from other subscriber.
+        6. Repeat step 3 and 4 for one subscriber where uni port is down.
+        7. Verify that subscriber should not get ip from dhcp server and other subscriber ping to gateway should not failed.
+        8. Enable onu port on which was disable at step 5 and ping to gateway from other subscriber.
+        9. Repeat step 3 and 4 for one subscriber where uni port is up now.
+        10. Verify that subscriber should get ip from dhcp server and other subscriber ping to gateway should not failed.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_disable_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Disable the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from dhcp server and other subscriber ping to gateway should failed.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_disable_enable_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Disable the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from dhcp server and other subscriber ping to gateway should failed.
+        8. Enable the olt device which is detected in voltha.
+        9. Verify that subscriber should get ip from dhcp server and other subscriber ping to gateway should not failed.
+        """
+    def test_two_subscriber_with_voltha_for_dhcp_pause_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to dhcp server which is running as onos app.
+        4. Verify that subscribers had got ip from dhcp server successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Pause the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from dhcp server and other subscriber ping to gateway should failed.
+        """
+    def test_subscriber_with_voltha_for_dhcpRelay_dhcp_request(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscrber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server successfully.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_dhcp_request_with_invalid_broadcast_source_mac(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with invalid source mac broadcast from residential subscrber to external dhcp server.
+        4. Verify that subscriber should not get ip from external dhcp server.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_dhcp_request_with_invalid_multicast_source_mac(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are is up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with invalid source mac multicast from residential subscrber to external dhcp server.
+        4. Verify that subscriber should not get ip from external dhcp server.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_dhcp_request_with_invalid_source_mac(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with invalid source mac zero from residential subscrber to external dhcp server.
+        4. Verify that subscriber should not get ip from external dhcp server.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_dhcp_request_and_release(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscrber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server successfully.
+        5. Send dhcp release from residential subscrber to external dhcp server.
+        6  Verify that subscriber should not get ip from external dhcp server, ping to gateway.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_starvation(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Repeat step 3 and 4 for 10 times.
+        6  Verify that subscriber should get ip from external dhcp server..
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_starvation_negative_scenario(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber without of pool ip to external dhcp server.
+        4. Verify that subscriber should not get ip from external dhcp server..
+        5. Repeat steps 3 and 4 for 10 times.
+        6  Verify that subscriber should not get ip from external dhcp server..
+        """
+    def test_subscriber_with_voltha_for_dhcpRelay_sending_multiple_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Repeat step 3 for 50 times.
+        6  Verify that subscriber should get same ip which was received from 1st discover from external dhcp server..
+        """
+    def test_subscriber_with_voltha_for_dhcpRelay_sending_multiple_request(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Send DHCP request to external dhcp server.
+        6. Repeat step 5 for 50 times.
+        7. Verify that subscriber should get same ip which was received from 1st discover from external dhcp server..
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_requesting_desired_ip_address(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired ip address from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip which was requested in step 3 from external dhcp server. successfully.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_requesting_desired_out_of_pool_ip_address(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired out of pool ip address from residential subscriber to external dhcp server.
+        4. Verify that subscriber should not get ip which was requested in step 3 from external dhcp server., and its offered only within dhcp pool of ip.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_deactivating_dhcpRelay_app_in_onos(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Deactivate dhcp server app in onos.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from external dhcp server., and ping to gateway.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_renew_time(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Send dhcp renew packet to external dhcp server.
+        6. Repeat step 4.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_rebind_time(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Send dhcp rebind packet to external dhcp server.
+        6. Repeat step 4.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_disable_olt_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Disable olt devices which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from external dhcp server., and ping to gateway.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_toggling_olt_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Disable olt devices which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from external dhcp server., and ping to gateway.
+        8. Enable olt devices which is being detected in voltha CLI.
+        9. Repeat steps 3 and 4.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_disable_onu_port_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Disable onu port which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from external dhcp server., and ping to gateway.
+        """
+
+    def test_subscriber_with_voltha_for_dhcpRelay_disable_enable_onu_port_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from residential subscriber to external dhcp server.
+        4. Verify that subscriber get ip from external dhcp server. successfully.
+        5. Disable onu port which is being detected in voltha CLI.
+        6. Repeat step 3.
+        7. Verify that subscriber should not get ip from external dhcp server., and ping to gateway.
+        8. Enable onu port which is being detected in voltha CLI.
+        9. Repeat steps 3 and 4.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got different ips from external dhcp server. successfully.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_multiple_discover(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Repeat step 3 and 4 for 10 times for both subscribers.
+        6  Verify that subscribers should get same ips which are offered the first time from external dhcp server..
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_multiple_discover_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Repeat step 3 and 4 for 10 times for only one subscriber and ping to gateway from other subscriber.
+        6  Verify that subscriber should get same ip which is offered the first time from external dhcp server. and other subscriber ping to gateway should not failed
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_discover_desired_ip_address_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from one residential subscriber to external dhcp server.
+        3. Send dhcp request with desired ip from other residential subscriber to external dhcp server.
+        4. Verify that subscribers had got different ips (one subscriber desired ip and other subscriber random ip) from external dhcp server. successfully.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_discover_in_range_and_out_of_range_from_dhcp_pool_ip_addresses(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request with desired wihtin dhcp pool ip from one residential subscriber to external dhcp server.
+        3. Send dhcp request with desired without in dhcp pool ip from other residential subscriber to external dhcp server.
+        4. Verify that subscribers had got different ips (both subscriber got random ips within dhcp pool) from external dhcp server. successfully.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_disable_onu_port_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Disable onu port on which access one subscriber and ping to gateway from other subscriber.
+        6. Repeat step 3 and 4 for one subscriber where uni port is down.
+        7. Verify that subscriber should not get ip from external dhcp server. and other subscriber ping to gateway should not failed.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_toggle_onu_port_for_one_subscriber(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Disable onu port on which access one subscriber and ping to gateway from other subscriber.
+        6. Repeat step 3 and 4 for one subscriber where uni port is down.
+        7. Verify that subscriber should not get ip from external dhcp server. and other subscriber ping to gateway should not failed.
+        8. Enable onu port on which was disable at step 5 and ping to gateway from other subscriber.
+        9. Repeat step 3 and 4 for one subscriber where uni port is up now.
+        10. Verify that subscriber should get ip from external dhcp server. and other subscriber ping to gateway should not failed.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_disable_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Disable the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from external dhcp server. and other subscriber ping to gateway should failed.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_toggle_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Disable the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from external dhcp server. and other subscriber ping to gateway should failed.
+        8. Enable the olt device which is detected in voltha.
+        9. Verify that subscriber should get ip from external dhcp server. and other subscriber ping to gateway should not failed.
+        """
+
+    def test_two_subscriber_with_voltha_for_dhcpRelay_pause_olt_detected_in_voltha(self):
+        """
+        Test Method:
+        0. Make sure that voltha and external dhcp server are up and running on CORD-POD setup.
+        1. OLT and ONU is detected and validated.
+        2. Issue  tls auth packets from CORD TESTER voltha test module acting as a subscriber..
+        3. Send dhcp request from two residential subscribers to external dhcp server.
+        4. Verify that subscribers had got ip from external dhcp server. successfully.
+        5. Start pinging continuously from one subscriber and repeat steps 3 and 4 for other subscriber.
+        6. Pause the olt device which is detected in voltha.
+        7. Verify that subscriber should not get ip from external dhcp server. and other subscriber ping to gateway should failed.
+        """
+