diff --git a/src/server/BreCal/api/shipcalls.py b/src/server/BreCal/api/shipcalls.py
index fbf552a..61a7a7c 100644
--- a/src/server/BreCal/api/shipcalls.py
+++ b/src/server/BreCal/api/shipcalls.py
@@ -3,7 +3,8 @@ from webargs.flaskparser import parser
 from marshmallow import Schema, fields, ValidationError
 from ..schemas import model
 from .. import impl
-from ..services.auth_guard import auth_guard
+from ..services.auth_guard import auth_guard, check_jwt
+from BreCal.validators.input_validation import check_if_user_is_bsmd_type, check_if_user_data_has_valid_ship_id, check_if_user_data_has_valid_berth_id, check_if_user_data_has_valid_participant_id
 
 import logging
 import json
@@ -40,6 +41,26 @@ def PostShipcalls():
     try:
         content = request.get_json(force=True)
         loadedModel = model.ShipcallSchema().load(data=content, many=False, partial=True)
+
+        # read the user data from the JWT token (set when login is performed)
+        user_data = check_jwt()
+
+        # check, whether the user belongs to a participant, which is of type ParticipantType.BSMD
+        # as ParticipantType is an IntFlag, a user belonging to multiple groups is properly evaluated.
+        is_bsmd = check_if_user_is_bsmd_type(user_data)
+        if not is_bsmd:
+            raise ValidationError(f"current user does not belong to BSMD. Cannot post shipcalls. Found user data: {user_data}")
+        
+        import logging
+        logging.log(20, loadedModel)
+        logging.log(20, "metz development")        
+        """
+        # loadedModel ...
+        valid_ship_id = check_if_user_data_has_valid_ship_id(ship_id)
+        valid_berth_id = check_if_user_data_has_valid_berth_id(berth_id)
+        valid_participant_id = check_if_user_data_has_valid_participant_id(participant_id)
+        """
+
         
     except ValidationError as ex:
         logging.error(ex)
diff --git a/src/server/BreCal/database/enums.py b/src/server/BreCal/database/enums.py
index 90726b3..5d28e65 100644
--- a/src/server/BreCal/database/enums.py
+++ b/src/server/BreCal/database/enums.py
@@ -2,7 +2,7 @@ from enum import IntEnum, Enum, IntFlag
 
 class ParticipantType(IntFlag):
     """determines the type of a participant"""
-    NONE = 0
+    undefined = 0
     BSMD = 1
     TERMINAL = 2
     PILOT = 4
@@ -13,10 +13,15 @@ class ParticipantType(IntFlag):
 
 class ShipcallType(IntEnum):
     """determines the type of a shipcall, as this changes the applicable validation rules"""
+    undefined = 0
     INCOMING = 1
     OUTGOING = 2
     SHIFTING = 3
 
+    @classmethod
+    def _missing_(cls, value):
+        return cls.undefined
+
 class ParticipantwiseTimeDelta():
     """stores the time delta for every participant, which triggers the validation rules in the rule set '0001'"""
     AGENCY = 1200.0 # 20 h * 60 min/h = 1200 min
@@ -42,10 +47,23 @@ class PierSide(IntEnum):
     """These enumerators determine the pier side of a shipcall."""
     PORTSIDE = 0 # Port/Backbord
     STARBOARD_SIDE = 1 # Starboard / Steuerbord
-
+        
 class NotificationType(IntFlag):
     """determines the method by which a notification is distributed to users. Flagging allows selecting multiple notification types."""
     UNDEFINED = 0
     EMAIL = 1
     POPUP = 2
     MESSENGER = 4
+
+class ParticipantFlag(IntFlag):
+    """
+    | 1 | If this flag is set on a shipcall record with participant type Agency (8), 
+    all participants of type BSMD (1) may edit the record.
+    """
+    undefined = 0
+    BSMD = 1
+
+    @classmethod
+    def _missing_(cls, value):
+        return cls.undefined
+
diff --git a/src/server/BreCal/database/sql_handler.py b/src/server/BreCal/database/sql_handler.py
index 59497e3..929f558 100644
--- a/src/server/BreCal/database/sql_handler.py
+++ b/src/server/BreCal/database/sql_handler.py
@@ -2,7 +2,7 @@ import numpy as np
 import pandas as pd
 import datetime
 import typing
-from BreCal.schemas.model import Shipcall, Ship, Participant, Berth, User, Times
+from BreCal.schemas.model import Shipcall, Ship, Participant, Berth, User, Times, ShipcallParticipantMap
 from BreCal.database.enums import ParticipantType
 
 def pandas_series_to_data_model():
@@ -50,7 +50,8 @@ class SQLHandler():
             'ship'->BreCal.schemas.model.Ship object
         """
         self.str_to_model_dict = {
-            "shipcall":Shipcall, "ship":Ship, "participant":Participant, "berth":Berth, "user":User, "times":Times
+            "shipcall":Shipcall, "ship":Ship, "participant":Participant, "berth":Berth, "user":User, "times":Times,
+            "shipcall_participant_map":ShipcallParticipantMap
         }
         return
 
@@ -70,12 +71,16 @@ class SQLHandler():
         data = [{k:v for k,v in zip(column_names, dat)} for dat in data]
 
         # 4.) build a dataframe from the respective data models (which ensures the correct data type)
+        df = self.build_df_from_data_and_name(data, table_name)
+        return df
+    
+    def build_df_from_data_and_name(self, data, table_name):
         data_model = self.str_to_model_dict.get(table_name)
         if data_model is not None:
-            df = pd.DataFrame([data_model(**dat) for dat in data])
+            df = pd.DataFrame([data_model(**dat) for dat in data], columns=list(data_model.__annotations__.keys()))
         else:
             df = pd.DataFrame([dat for dat in data])
-        return df
+        return df 
 
     def mysql_to_df(self, query, table_name):
         """provide an arbitrary sql query that should be read from a mysql server {sql_connection}. returns a pandas DataFrame with the obtained data"""
@@ -94,11 +99,7 @@ class SQLHandler():
 
         # 4.) build a dataframe from the respective data models (which ensures the correct data type)
         data_model = self.str_to_model_dict.get(table_name)
-        if data_model is not None:
-            df = pd.DataFrame([data_model(**dat) for dat in data])
-        else:
-            df = pd.DataFrame([dat for dat in data])
-        
+        df = self.build_df_from_data_and_name(data, table_name)
         if 'id' in df.columns:
             df = df.set_index('id', inplace=False) # avoid inplace updates, so the raw sql remains unchanged
         return df
diff --git a/src/server/BreCal/impl/shipcalls.py b/src/server/BreCal/impl/shipcalls.py
index 8d15983..252c817 100644
--- a/src/server/BreCal/impl/shipcalls.py
+++ b/src/server/BreCal/impl/shipcalls.py
@@ -60,8 +60,13 @@ def PostShipcalls(schemaModel):
     """
 
     :param schemaModel: The deserialized dict of the request
+    e.g.,
+        {
+            'ship_id': 1, 'type': 1, 'eta': datetime.datetime(2023, 7, 23, 7, 18, 19), 
+            'voyage': '43B', 'tug_required': False, 'pilot_required': True, 'flags': 0, 
+            'pier_side': False, 'bunkering': True, 'recommended_tugs': 2, 'type_value': 1, 'evaluation_value': 0}
+        }
     """
-
     # TODO: Validate the upload data
 
     # This creates a *new* entry
@@ -133,7 +138,6 @@ def PostShipcalls(schemaModel):
         # if not full_id_existances:
         # pooledConnection.close()
         # return json.dumps({"message" : "call failed. missing mandatory keywords."}), 500, {'Content-Type': 'application/json; charset=utf-8'}
-
         commands.execute(query, schemaModel)
         new_id = commands.execute_scalar("select last_insert_id()")
 
diff --git a/src/server/BreCal/local_db.py b/src/server/BreCal/local_db.py
index 4293ff3..b4e02cd 100644
--- a/src/server/BreCal/local_db.py
+++ b/src/server/BreCal/local_db.py
@@ -7,11 +7,11 @@ import sys
 
 config_path = None
 
-def initPool(instancePath):
+def initPool(instancePath, connection_filename="connection_data_devel.json"):
     try:
         global config_path
         if(config_path == None):
-            config_path = os.path.join(instancePath,'../../../secure/connection_data_devel.json');
+            config_path = os.path.join(instancePath,f'../../../../secure/{connection_filename}') #connection_data_devel.json');
 
         print (config_path)
 
diff --git a/src/server/BreCal/schemas/model.py b/src/server/BreCal/schemas/model.py
index 0df42c8..33638fd 100644
--- a/src/server/BreCal/schemas/model.py
+++ b/src/server/BreCal/schemas/model.py
@@ -10,6 +10,9 @@ from typing import List
 import json
 import datetime
 from BreCal.validators.time_logic import validate_time_exceeds_threshold
+from BreCal.database.enums import ParticipantType, ParticipantFlag
+
+# from BreCal. ... import check_if_user_is_bsmd_type
 
 def obj_dict(obj):
     if isinstance(obj, datetime.datetime):
@@ -54,6 +57,7 @@ class NotificationType(IntEnum):
     undefined = 0
     email = 1
     push = 2
+    
     @classmethod
     def _missing_(cls, value):
         return cls.undefined
@@ -143,12 +147,34 @@ class Participant(Schema):
     street: str
     postal_code: str
     city: str
-    type: int
+    type: int # fields.Enum(ParticipantType ...)
     flags: int
     created: datetime
     modified: datetime
     deleted: bool
 
+    @validates("type")
+    def validate_type(self, value):
+        # e.g., when an IntFlag has the values 1,2,4; the maximum valid value is 7
+        max_int = sum([int(val) for val in list(ParticipantType._value2member_map_.values())])
+        min_int = 0
+
+        valid_type = 0 <= value < max_int  
+        if not valid_type:
+            raise ValidationError(f"the provided integer is not supported for default behaviour of the ParticipantType IntFlag. Your choice: {value}. Supported values are: 0 <= value {max_int}")
+
+
+    @validates("flags")
+    def validate_type(self, value):
+        # e.g., when an IntFlag has the values 1,2,4; the maximum valid value is 7
+        max_int = sum([int(val) for val in list(ParticipantFlag._value2member_map_.values())])
+        min_int = 0
+
+        valid_type = 0 <= value < max_int  
+        if not valid_type:
+            raise ValidationError(f"the provided integer is not supported for default behaviour of the ParticipantFlag IntFlag. Your choice: {value}. Supported values are: 0 <= value {max_int}")
+
+
 class ParticipantList(Participant):
     pass
 
@@ -163,7 +189,8 @@ class ShipcallSchema(Schema):
 
     id = fields.Integer()
     ship_id = fields.Integer()
-    type = fields.Integer()
+    #type = fields.Enum(ShipcallType, default=ShipcallType.undefined) # type = fields.Integer() # make enum: shipcall type. add validator
+    type = fields.Integer() # make enum: shipcall type. add validator # type = fields.Enum(ShipcallType, default=ShipcallType.undefined) # type = fields.Integer() # make enum: shipcall type. add validator
     eta = fields.DateTime(metadata={'required':False}, allow_none=True)
     voyage = fields.String(allow_none=True, metadata={'Required':False}, validate=[validate.Length(max=16)]) # Solving: RemovedInMarshmallow4Warning: Passing field metadata as keyword arguments is deprecated. Use the explicit `metadata=...` argument instead. Additional metadata: {'Required': False}
     etd = fields.DateTime(metadata={'required':False}, allow_none=True)
@@ -196,15 +223,23 @@ class ShipcallSchema(Schema):
     @post_load
     def make_shipcall(self, data, **kwargs):
         if 'type' in data:
-            data['type_value'] = data['type'].value
+            data['type_value'] = int(data['type'])
         else:
-            data['type_value'] = ShipcallType.undefined
+            data['type_value'] = int(ShipcallType.undefined)
         if 'evaluation' in data:
             if data['evaluation']:
-                data['evaluation_value'] = data['evaluation'].value           
+                data['evaluation_value'] = int(data['evaluation'])           
         else:
-            data['evaluation_value'] = EvaluationType.undefined
+            data['evaluation_value'] = int(EvaluationType.undefined)
         return data
+    
+    @validates("type")
+    def validate_type(self, value):
+        valid_shipcall_type = int(value) in [item.value for item in ShipcallType]
+        
+        if not valid_shipcall_type:
+            raise ValidationError(f"the provided type is not a valid shipcall type.")
+
 
 @dataclass
 class Participant_Assignment:
@@ -321,7 +356,7 @@ class TimesSchema(Schema):
     berth_info = fields.String(metadata={'required':False}, allow_none=True, validate=[validate.Length(max=256)])
     pier_side = fields.Bool(metadata={'required':False}, allow_none = True)
     shipcall_id = fields.Integer(metadata={'required':True})
-    participant_type = fields.Integer(metadata={'required':False}, allow_none=True)
+    participant_type = fields.Enum(ParticipantType, metadata={'required':False}, allow_none=True, default=ParticipantType.undefined) #fields.Integer(metadata={'required':False}, allow_none=True)
     ata = fields.DateTime(metadata={'required':False}, allow_none=True)
     atd = fields.DateTime(metadata={'required':False}, allow_none=True)
     eta_interval_end = fields.DateTime(metadata={'required':False}, allow_none=True)
@@ -463,3 +498,22 @@ class Shipcalls(Shipcall):
 
 class TimesList(Times):
     pass
+
+@dataclass
+class ShipcallParticipantMap:
+    id: int
+    shipcall_id: int
+    participant_id: int
+    type : ShipcallType
+    created: datetime
+    modified: datetime
+
+    def to_json(self):
+        return {
+            "id": self.id,
+            "shipcall_id": self.shipcall_id,
+            "participant_id": self.participant_id,
+            "type": self.type.name,
+            "created": self.created.isoformat() if self.created else "",
+            "modified": self.modified.isoformat() if self.modified else "",
+        }
diff --git a/src/server/BreCal/services/auth_guard.py b/src/server/BreCal/services/auth_guard.py
index 9c5824d..9bd27c6 100644
--- a/src/server/BreCal/services/auth_guard.py
+++ b/src/server/BreCal/services/auth_guard.py
@@ -9,6 +9,7 @@ def check_jwt():
     if not token:
         raise Exception('Missing access token')
     jwt = token.split('Bearer ')[1]
+
     try:
         return decode_jwt(jwt)
     except Exception as e:
diff --git a/src/server/BreCal/services/jwt_handler.py b/src/server/BreCal/services/jwt_handler.py
index 66c0f43..b3c80e7 100644
--- a/src/server/BreCal/services/jwt_handler.py
+++ b/src/server/BreCal/services/jwt_handler.py
@@ -7,11 +7,26 @@ def create_api_key():
     return secrets.token_urlsafe(16)
 
 def generate_jwt(payload, lifetime=None):
+    """
+    creates an encoded token, which is based on the 'SECRET_KEY' environment variable. The environment variable
+    is set when the .wsgi application is started or can theoretically be set on system-level.
+
+    args:
+        payload:
+            json-dictionary with key:value pairs. 
+
+        lifetime:
+            When a 'lifetime' (integer) is provided, the payload will be extended by an expiration key 'exp', which is
+            valid for the next {lifetime} minutes. 
+
+    returns: token, a JWT-encoded string
+    """
     if lifetime:
         payload['exp'] = (datetime.datetime.now() + datetime.timedelta(minutes=lifetime)).timestamp()
     return jwt.encode(payload, os.environ.get('SECRET_KEY'), algorithm="HS256")
 
 def decode_jwt(token):
+    """this function reverts the {generate_jwt} function. An encoded JWT token is decoded into a JSON dictionary."""
     return jwt.decode(token, os.environ.get('SECRET_KEY'), algorithms=["HS256"])
 
 
diff --git a/src/server/BreCal/stubs/shipcall.py b/src/server/BreCal/stubs/shipcall.py
index 2e4e154..3f5c062 100644
--- a/src/server/BreCal/stubs/shipcall.py
+++ b/src/server/BreCal/stubs/shipcall.py
@@ -7,21 +7,21 @@ def get_shipcall_simple():
     # only used for the stub
     base_time = datetime.datetime.now()
 
-    shipcall_id = generate_uuid1_int()
-    ship_id = generate_uuid1_int()
+    shipcall_id = 124 # generate_uuid1_int()
+    ship_id = 5 # generate_uuid1_int()
 
     eta = base_time+datetime.timedelta(hours=3, minutes=12)
     role_type = 1
     voyage = "987654321"
     etd = base_time+datetime.timedelta(hours=6, minutes=12) # should never be before eta
 
-    arrival_berth_id = generate_uuid1_int()
-    departure_berth_id = generate_uuid1_int()
+    arrival_berth_id = 140 #generate_uuid1_int()
+    departure_berth_id = 140 #generate_uuid1_int()
 
     tug_required = False
     pilot_required = False
 
-    flags = 0 # #TODO_shipcall_flags. What is meant here? What should be tested?
+    flags = 0 # #TODO_shipcall_flags. What is meant here? What should be tested? 
     pier_side = False # whether a ship will be fixated on the pier side. en: pier side, de: Anlegestelle. From 'BremenCalling_Datenmodell.xlsx': gedreht/ungedreht
     bunkering = False # #TODO_bunkering_unclear
     replenishing_terminal = False # en: replenishing terminal, de: Nachfüll-Liegeplatz
@@ -38,11 +38,13 @@ def get_shipcall_simple():
     anchored = False
     moored_lock = False # de: 'Festmacherschleuse', en: 'moored lock'
     canceled = False
+    
+    time_ref_point = 0
 
     evaluation = None
     evaluation_message = ""
-    evaluation_time = None
-    evaluation_notifications_sent = None
+    evaluation_time = datetime.datetime.now()
+    evaluation_notifications_sent = False
     created = datetime.datetime.now()
     modified = created+datetime.timedelta(seconds=10)
 
@@ -76,6 +78,7 @@ def get_shipcall_simple():
         evaluation_message,
         evaluation_time,
         evaluation_notifications_sent,
+        time_ref_point,
         created,
         modified,
         participants,
diff --git a/src/server/BreCal/validators/input_validation.py b/src/server/BreCal/validators/input_validation.py
index 188e5e4..2248779 100644
--- a/src/server/BreCal/validators/input_validation.py
+++ b/src/server/BreCal/validators/input_validation.py
@@ -1,8 +1,91 @@
 
 ####################################### InputValidation #######################################
 
+import json
 from abc import ABC, abstractmethod
 from BreCal.schemas.model import Ship, Shipcall, Berth, User, Participant
+from BreCal.impl.participant import GetParticipant
+from BreCal.impl.ships import GetShips
+from BreCal.impl.berths import GetBerths
+
+from BreCal.database.enums import ParticipantType
+
+def get_participant_id_dictionary():
+    # get all participants
+    response,status_code,header = GetParticipant(options={})
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = json.loads(response)
+    participants = {items.get("id"):items for items in participants}
+    return participants
+
+def get_ship_id_dictionary():
+    # get all ships
+    response,status_code,header = GetShips(token=None)
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    ships = json.loads(response)
+    ships = {items.get("id"):items for items in ships}
+    return ships
+
+def get_berth_id_dictionary():
+    # get all berths
+    response,status_code,header = GetBerths(token=None)
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    berths = json.loads(response)
+    berths = {items.get("id"):items for items in berths}
+    return berths
+
+def check_if_user_is_bsmd_type(user_data:dict)->bool:
+    """
+    given a dictionary of user data, determine the respective participant id and read, whether
+    that participant is a .BSMD-type
+
+    Note: ParticipantType is an IntFlag. 
+        Hence, ParticipantType(1) is ParticipantType.BSMD,
+        and ParticipantType(7) is [ParticipantType.BSMD, ParticipantType.TERMINAL, ParticipantType.PILOT]
+
+        both would return 'True'
+
+    returns: boolean. Whether the participant id is a .BSMD type element
+    """
+    # user_data = decode token
+    participant_id = user_data.get("participant_id")
+
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = get_participant_id_dictionary()
+    participant = participants.get(participant_id,{})
+
+    # boolean check: is the participant of type .BSMD?
+    is_bsmd = ParticipantType.BSMD in ParticipantType(participant.get("type",0)) 
+    return is_bsmd
+
+def check_if_user_data_has_valid_ship_id(ship_id):
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    ships = get_ship_id_dictionary()
+    
+    # boolean check
+    ship_id_is_valid = ship_id in list(ships.keys())
+    return ship_id_is_valid
+
+def check_if_user_data_has_valid_berth_id(berth_id):
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    berths = get_berth_id_dictionary()
+
+    # boolean check
+    berth_id_is_valid = berth_id in list(berths.keys())
+    return berth_id_is_valid
+
+def check_if_user_data_has_valid_participant_id(participant_id):
+    # build a dictionary of id:item pairs, so one can select the respective participant
+    participants = get_participant_id_dictionary()
+
+    # boolean check
+    participant_id_is_valid = participant_id in list(participants.keys())
+    return participant_id_is_valid
+
+
 
 class InputValidation():
     def __init__(self):
diff --git a/src/server/requirements.txt b/src/server/requirements.txt
index 8b7f3ad..23bf276 100644
--- a/src/server/requirements.txt
+++ b/src/server/requirements.txt
@@ -8,6 +8,7 @@ webargs==6.1.1
 Werkzeug==1.0.1
 pydapper[mysql-connector-python]
 marshmallow-dataclass
+marshmallow-enum
 bcrypt
 pyjwt
 flask-jwt-extended
@@ -20,4 +21,4 @@ pytest
 pytest-cov
 coverage
 
-../server/.
+-e ../server/.
diff --git a/src/server/tests/test_create_app.py b/src/server/tests/test_create_app.py
index 652ae3d..46ede88 100644
--- a/src/server/tests/test_create_app.py
+++ b/src/server/tests/test_create_app.py
@@ -8,7 +8,7 @@ def test_create_app():
     import sys
     from BreCal import get_project_root
 
-    project_root = get_project_root("brecal")
+    project_root = os.path.join(os.path.expanduser("~"), "brecal")
     lib_location = os.path.join(project_root, "src", "server")
     sys.path.append(lib_location)
 
diff --git a/src/server/tests/validators/test_validation_rule_functions.py b/src/server/tests/validators/test_validation_rule_functions.py
index fdd8152..3a08735 100644
--- a/src/server/tests/validators/test_validation_rule_functions.py
+++ b/src/server/tests/validators/test_validation_rule_functions.py
@@ -12,7 +12,17 @@ from BreCal.stubs.df_times import get_df_times, random_time_perturbation, get_df
 @pytest.fixture(scope="session")
 def build_sql_proxy_connection():
     import mysql.connector
-    conn_from_pool = mysql.connector.connect(**{'host':'localhost', 'port':3306, 'user':'root', 'password':'HalloWach_2323XXL!!', 'pool_name':'brecal_pool', 'pool_size':20, 'database':'bremen_calling', 'autocommit': True})
+    import os
+    import json
+    connection_data_path = os.path.join(os.path.expanduser("~"),"secure","connection_data_local.json")
+    assert os.path.exists(connection_data_path)
+
+    with open(connection_data_path, "r") as jr:
+       connection_data = json.load(jr)
+       connection_data = {k:v for k,v in connection_data.items() if k in ["host", "port", "user", "password", "pool_size", "pool_name", "database"]}
+       
+    conn_from_pool = mysql.connector.connect(**connection_data)
+    #conn_from_pool = mysql.connector.connect(**{'host':'localhost', 'port':3306, 'user':'root', 'password':'HalloWach_2323XXL!!', 'pool_name':'brecal_pool', 'pool_size':20, 'database':'bremen_calling_local', 'autocommit': True})
     sql_handler = SQLHandler(sql_connection=conn_from_pool, read_all=True)
     vr = ValidationRules(sql_handler)
     return locals()