diff --git a/src/context/service/database/Service.py b/src/context/service/database/Service.py
index a81a80c3c2398fed16842bcc3d8aa16342edb72b..fe12eaf8a011e2ae4861c64cdfac8c4b9c388731 100644
--- a/src/context/service/database/Service.py
+++ b/src/context/service/database/Service.py
@@ -91,6 +91,7 @@ def service_set(db_engine : Engine, request : Service) -> Tuple[Dict, bool]:
         service_endpoints_data.append({
             'service_uuid' : service_uuid,
             'endpoint_uuid': endpoint_uuid,
+            'position'     : i,
         })
 
     constraints = compose_constraints_data(request.service_constraints, now, service_uuid=service_uuid)
diff --git a/src/context/service/database/Slice.py b/src/context/service/database/Slice.py
index 1d6781d53f7c85d8cb878b1b38b0de65b4ef5726..724046bfae16ea8e75ba84b83ff52c1050242003 100644
--- a/src/context/service/database/Slice.py
+++ b/src/context/service/database/Slice.py
@@ -91,6 +91,7 @@ def slice_set(db_engine : Engine, request : Slice) -> Tuple[Dict, bool]:
         slice_endpoints_data.append({
             'slice_uuid'   : slice_uuid,
             'endpoint_uuid': endpoint_uuid,
+            'position'     : i,
         })
 
     slice_services_data : List[Dict] = list()
diff --git a/src/context/service/database/models/ServiceModel.py b/src/context/service/database/models/ServiceModel.py
index 09ff381b5eb374ea752590bba5403fe816319036..f1781c4f86fa25e8d9f3e42da46451e112ef779e 100644
--- a/src/context/service/database/models/ServiceModel.py
+++ b/src/context/service/database/models/ServiceModel.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 
 import operator
-from sqlalchemy import Column, DateTime, Enum, ForeignKey, String
+from sqlalchemy import CheckConstraint, Column, DateTime, Enum, ForeignKey, Integer, String
 from sqlalchemy.dialects.postgresql import UUID
 from sqlalchemy.orm import relationship
 from typing import Dict
@@ -51,7 +51,7 @@ class ServiceModel(_Base):
             'service_status'      : {'service_status': self.service_status.value},
             'service_endpoint_ids': [
                 service_endpoint.endpoint.dump_id()
-                for service_endpoint in self.service_endpoints
+                for service_endpoint in sorted(self.service_endpoints, key=operator.attrgetter('position'))
             ],
             'service_constraints' : [
                 constraint.dump()
@@ -68,6 +68,11 @@ class ServiceEndPointModel(_Base):
 
     service_uuid  = Column(ForeignKey('service.service_uuid',   ondelete='CASCADE' ), primary_key=True)
     endpoint_uuid = Column(ForeignKey('endpoint.endpoint_uuid', ondelete='RESTRICT'), primary_key=True, index=True)
+    position      = Column(Integer, nullable=False)
 
     service  = relationship('ServiceModel',  back_populates='service_endpoints', lazy='joined')
     endpoint = relationship('EndPointModel', lazy='joined') # back_populates='service_endpoints'
+
+    __table_args__ = (
+        CheckConstraint(position >= 0, name='check_position_value'),
+    )
diff --git a/src/context/service/database/models/SliceModel.py b/src/context/service/database/models/SliceModel.py
index 2d6c884169154fee8d44c26464416c6708c650b1..7f1550eb2ebb80962bac94374112d43785184374 100644
--- a/src/context/service/database/models/SliceModel.py
+++ b/src/context/service/database/models/SliceModel.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 
 import operator
-from sqlalchemy import Column, DateTime, Enum, ForeignKey, String
+from sqlalchemy import CheckConstraint, Column, DateTime, Enum, ForeignKey, Integer, String
 from sqlalchemy.dialects.postgresql import UUID
 from sqlalchemy.orm import relationship
 from typing import Dict
@@ -53,7 +53,7 @@ class SliceModel(_Base):
             'slice_status'      : {'slice_status': self.slice_status.value},
             'slice_endpoint_ids': [
                 slice_endpoint.endpoint.dump_id()
-                for slice_endpoint in self.slice_endpoints
+                for slice_endpoint in sorted(self.slice_endpoints, key=operator.attrgetter('position'))
             ],
             'slice_constraints' : [
                 constraint.dump()
@@ -82,10 +82,15 @@ class SliceEndPointModel(_Base):
 
     slice_uuid    = Column(ForeignKey('slice.slice_uuid',       ondelete='CASCADE' ), primary_key=True)
     endpoint_uuid = Column(ForeignKey('endpoint.endpoint_uuid', ondelete='RESTRICT'), primary_key=True, index=True)
+    position      = Column(Integer, nullable=False)
 
     slice    = relationship('SliceModel', back_populates='slice_endpoints', lazy='joined')
     endpoint = relationship('EndPointModel', lazy='joined') # back_populates='slice_endpoints'
 
+    __table_args__ = (
+        CheckConstraint(position >= 0, name='check_position_value'),
+    )
+
 class SliceServiceModel(_Base):
     __tablename__ = 'slice_service'