diff --git a/cli/xpon.py b/cli/xpon.py
index 7e3d8c2..b6d5c03 100644
--- a/cli/xpon.py
+++ b/cli/xpon.py
@@ -1479,7 +1479,7 @@
         self.poutput(
 '''
 tcont [get | create | update | delete] [-n <name>] [-r <interface reference>]
-      [-t <traffic descriptor profile reference>]
+      [-t <traffic descriptor profile reference>] [-a alloc-id ]
 
 get:    displays existing tconts
         Required flags: None
@@ -1495,10 +1495,12 @@
 -n: <string> name of tcont.
 -r: <string> reference to vont ani interface.
 -t: <string> reference to an existing traffic descriptor profile.
+-a: <int>    allocation ID (alloc-id) for the TCONT. If not provided, xPON
+             Manager will provide the alloc-id for the TCONT.
 
 Example:
 
-tcont create -n "TCont 1" -r "Golden User" -t "TDP 1"
+tcont create -n "TCont 1" -r "Golden User" -t "TDP 1" -a 1024
 '''
         )
 
@@ -1512,6 +1514,8 @@
                     dest='traffic_descriptor_profile_ref', type='string',
                     help='reference to an existing traffic descriptor profile',
                     default=None),
+        make_option('-a', '--alloc_id', action='store', dest='alloc_id',
+                    type='int', help='alloc-id', default=None),
     ])
 
     def do_tcont(self, line, opts):
@@ -1545,6 +1549,8 @@
             if opts.traffic_descriptor_profile_ref:
                 tcont.traffic_descriptor_profile_ref = \
                     opts.traffic_descriptor_profile_ref
+            if opts.alloc_id:
+                tcont.alloc_id = opts.alloc_id
             if line.strip() == "create":
                 stub.CreateTcontsConfigData(tcont)
             elif line.strip() == "update":
@@ -1585,10 +1591,11 @@
 -t: <string> tcont reference that is for the purpose of upstream scheduling in
              the ONU, a gemport needs to refer to the tcont into which it feeds
              upstream traffic.
+-g: <int>    gemport ID. If not provided, xPON Manager will provide the gemport ID.
 
 Example:
 
-gem_port create -n "GEMPORT 1" -r "Enet UNI 1" -c 0 -a true -t "TCont 1"
+gem_port create -n "GEMPORT 1" -r "Enet UNI 1" -c 0 -a true -t "TCont 1" -g 2044
 '''
         )
 
@@ -1609,6 +1616,8 @@
                     type='string',
                     help='tcont reference for purpose of us scheduling in ONU',
                     default=None),
+        make_option('-g', '--gemport_id', action='store', dest='gemport_id',
+                    type='int', help='GEMPORT ID', default=None),
     ])
 
     def do_gem_port(self, line, opts):
@@ -1656,6 +1665,8 @@
                     return
             if opts.tcont_ref:
                 gemport.tcont_ref = opts.tcont_ref
+            if opts.gemport_id:
+                gemport.gemport_id = opts.gemport_id
             if line.strip() == "create":
                 stub.CreateGemportsConfigData(gemport)
             elif line.strip() == "update":
diff --git a/common/utils/indexpool.py b/common/utils/indexpool.py
index 24f57ff..d85d1ef 100644
--- a/common/utils/indexpool.py
+++ b/common/utils/indexpool.py
@@ -18,6 +18,21 @@
             log.info("exception-fail-to-allocate-id-all-bits-in-use")
             return None
 
+    def allocate(self, index):
+        try:
+            _pos = index - self.offset
+            if not (0 <= _pos < self.max_entries):
+                log.info("{}-out-of-range".format(index))
+                return None
+            if self.indices[_pos]:
+                log.info("{}-is-already-allocated".format(index))
+                return None
+            self.indices.set(1, _pos)
+            return index
+
+        except IndexError:
+            return None
+
     def release(self, index):
         index -= self.offset
         _pos = (index,)
diff --git a/tests/itests/voltha/test_voltha_xpon.py b/tests/itests/voltha/test_voltha_xpon.py
index 2413457..39dcdfc 100644
--- a/tests/itests/voltha/test_voltha_xpon.py
+++ b/tests/itests/voltha/test_voltha_xpon.py
@@ -170,6 +170,26 @@
             }
         }
     },
+    {'tcont-add-with-alloc-id': {
+        'pb2': tcont.TcontsConfigData(),
+        'rpc': {
+            "interface_reference": "Golden User",
+            "traffic_descriptor_profile_ref": "TDP 1",
+            "name": "TCont 2",
+            "alloc_id": 1234
+            }
+        }
+    },
+    {'tcont-add-with-alloc-id-zero': {
+        'pb2': tcont.TcontsConfigData(),
+        'rpc': {
+            "interface_reference": "Golden User",
+            "traffic_descriptor_profile_ref": "TDP 1",
+            "name": "TCont 3",
+            "alloc_id": 0
+            }
+        }
+    },
     {'gemport-add': {
         'pb2': gemport.GemportsConfigData(),
         'rpc': {
@@ -180,6 +200,30 @@
             "tcont_ref": "TCont 1",
             }
         }
+    },
+    {'gemport-add-with-gemport-id': {
+        'pb2': gemport.GemportsConfigData(),
+        'rpc': {
+            "aes_indicator": True,
+            "name": "GEMPORT 2",
+            "traffic_class": 0,
+            "itf_ref": "Enet UNI 1",
+            "tcont_ref": "TCont 2",
+            "gemport_id": 2345
+            }
+        }
+    },
+    {'gemport-add-with-gemport-id-zero': {
+        'pb2': gemport.GemportsConfigData(),
+        'rpc': {
+            "aes_indicator": True,
+            "name": "GEMPORT 2",
+            "traffic_class": 0,
+            "itf_ref": "Enet UNI 1",
+            "tcont_ref": "TCont 2",
+            "gemport_id": 0
+            }
+        }
     }
 ]
 
diff --git a/voltha/core/xpon_handler.py b/voltha/core/xpon_handler.py
index c102c1a..babaa7c 100644
--- a/voltha/core/xpon_handler.py
+++ b/voltha/core/xpon_handler.py
@@ -915,9 +915,16 @@
             assert self.validate_interface(request, context)
             cg_name = self.extract_channel_group_from_request(request,
                         'v_ont_anis', request.interface_reference)
-            _id = self.cg_dict[cg_name]['alloc_id'].get_next()
-            assert _id != None
-            request.alloc_id = _id
+            if request.alloc_id == 0:
+                _id = self.cg_dict[cg_name]['alloc_id'].get_next()
+                assert _id is not None, \
+                    'Fail to allocate id for TCont'
+                request.alloc_id = _id
+            else:
+                _id = self.cg_dict[cg_name]['alloc_id'].allocate(request.alloc_id)
+                assert _id == request.alloc_id, \
+                    'Fail to allocate id for TCont'
+
             log.debug('creating-tcont', name=request.name)
             self.root.add('/tconts', request)
             return Empty()
@@ -1012,10 +1019,16 @@
             assert self.validate_interface(request, context)
             cg_name = self.extract_channel_group_from_request(request,
                         'v_enets', request.itf_ref)
-            _id = self.cg_dict[cg_name]['gemport_id'].get_next()
-            assert _id != None, \
-                'Fail to allocate id for CemPort'
-            request.gemport_id = _id
+            if request.gemport_id == 0:
+                _id = self.cg_dict[cg_name]['gemport_id'].get_next()
+                assert _id is not None, \
+                    'Fail to allocate id for GemPort'
+                request.gemport_id = _id
+            else:
+                _id = self.cg_dict[cg_name]['gemport_id'].allocate(request.gemport_id)
+                assert _id == request.gemport_id, \
+                    'Fail to allocate id for GemPort'
+
             log.debug('creating-gemport', name=request.name)
             self.root.add('/gemports', request)
             return Empty()
diff --git a/voltha/protos/bbf_fiber_gemport_body.proto b/voltha/protos/bbf_fiber_gemport_body.proto
index b78d84d..b08af06 100644
--- a/voltha/protos/bbf_fiber_gemport_body.proto
+++ b/voltha/protos/bbf_fiber_gemport_body.proto
@@ -10,7 +10,7 @@
     uint32 traffic_class = 4;
     bool aes_indicator = 5;
     string tcont_ref = 6;
-    uint32 gemport_id = 7 [(voltha.access) = READ_ONLY];
+    uint32 gemport_id = 7;
 }
 message GemportsOperData {
     string id = 1 [(voltha.access) = READ_ONLY];
diff --git a/voltha/protos/bbf_fiber_tcont_body.proto b/voltha/protos/bbf_fiber_tcont_body.proto
index 03f42b0..2c24e32 100644
--- a/voltha/protos/bbf_fiber_tcont_body.proto
+++ b/voltha/protos/bbf_fiber_tcont_body.proto
@@ -8,7 +8,7 @@
     string name = 2;
     string interface_reference = 3;
     string traffic_descriptor_profile_ref = 4;
-    uint32 alloc_id = 5 [(voltha.access) = READ_ONLY];
+    uint32 alloc_id = 5;
 }
 message TcontsOperData {
     string id = 1 [(voltha.access) = READ_ONLY];