diff --git a/tests/unit_tests/primaite/__init__.py b/src/primaite/simulator/network/__init__.py
similarity index 100%
rename from tests/unit_tests/primaite/__init__.py
rename to src/primaite/simulator/network/__init__.py
diff --git a/src/primaite/simulator/network/physical_layer.py b/src/primaite/simulator/network/physical_layer.py
new file mode 100644
index 00000000..bb4b120e
--- /dev/null
+++ b/src/primaite/simulator/network/physical_layer.py
@@ -0,0 +1,222 @@
+from __future__ import annotations
+
+import re
+import secrets
+from ipaddress import IPv4Address
+from typing import Dict, List, Optional
+
+from primaite.simulator.core import SimComponent
+
+
+def generate_mac_address(oui: Optional[str] = None) -> str:
+    """
+    Generate a random MAC Address..
+
+    :Example:
+
+    >>> generate_mac_address()
+    'ef:7e:97:c8:a8:ce'
+
+    >>> generate_mac_address(oui='aa:bb:cc')
+    'aa:bb:cc:42:ba:41'
+
+    :param oui: The Organizationally Unique Identifier (OUI) portion of the MAC address. It should be a string with
+        the first 3 bytes (24 bits) in the format "XX:XX:XX".
+    :raises ValueError: If the 'oui' is not in the correct format (hexadecimal and 6 characters).
+    """
+    random_bytes = [secrets.randbits(8) for _ in range(6)]
+
+    if oui:
+        oui_pattern = re.compile(r"^([0-9A-Fa-f]{2}[:-]){2}[0-9A-Fa-f]{2}$")
+        if not oui_pattern.match(oui):
+            raise ValueError(
+                f"Invalid oui. The oui should be in the format 'xx:xx:xx', where x is a hexadecimal digit, got '{oui}'."
+            )
+        oui_bytes = [int(chunk, 16) for chunk in oui.split(":")]
+        mac = oui_bytes + random_bytes[len(oui_bytes) :]
+    else:
+        mac = random_bytes
+
+    return ":".join(f"{b:02x}" for b in mac)
+
+
+class Link(SimComponent):
+    """
+    Represents a network link between two network interface cards (NICs).
+
+    :param endpoint_a: The first NIC connected to the Link.
+    :type endpoint_a: NIC
+    :param endpoint_b: The second NIC connected to the Link.
+    :type endpoint_b: NIC
+    :param bandwidth: The bandwidth of the Link in Mbps (default is 100 Mbps).
+    :type bandwidth: int
+    """
+
+    endpoint_a: NIC
+    endpoint_b: NIC
+    bandwidth: int
+    current_load: int = 0
+
+    def __init__(self, endpoint_a: NIC, endpoint_b: NIC, bandwidth: int = 100):
+        """
+        Initialize the Link instance.
+
+        When a Link is created, it automatically connects the endpoints to itself.
+
+        :param endpoint_a: The first NIC connected to the link.
+        :type endpoint_a: NIC
+        :param endpoint_b: The second NIC connected to the link.
+        :type endpoint_b: NIC
+        :param bandwidth: The bandwidth of the link in Mbps (default is 100 Mbps).
+        :type bandwidth: int
+        :raise ValueError: If endpoint_a equals endpoint_b.
+        """
+        super().__init__(endpoint_a=endpoint_a, endpoint_b=endpoint_b, bandwidth=bandwidth)
+        if self.endpoint_a == self.endpoint_b:
+            raise ValueError("endpoint_a and endpoint_b cannot be the same NIC")
+
+    def send_frame(self, sender_nic: NIC, frame):
+        """
+        Send a network frame from one NIC to another connected NIC.
+
+        :param sender_nic: The NIC sending the frame.
+        :type sender_nic: NIC
+        :param frame: The network frame to be sent.
+        :type frame: Frame
+        """
+        pass
+
+    def receive_frame(self, sender_nic: NIC, frame):
+        """
+        Receive a network frame from a connected NIC.
+
+        :param sender_nic: The NIC sending the frame.
+        :type sender_nic: NIC
+        :param frame: The network frame being received.
+        :type frame: Frame
+        """
+        pass
+
+    def describe_state(self) -> Dict:
+        """
+        Get the current state of the Libk as a dict.
+
+        :return: A dict containing the current state of the Link.
+        """
+        pass
+
+    def apply_action(self, action: str):
+        """
+        Apply an action to the Link.
+
+        :param action: The action to be applied.
+        :type action: str
+        """
+        pass
+
+
+class NIC(SimComponent):
+    """
+    Models a Network Interface Card (NIC) in a computer or network device.
+
+    :param ip_address: The IPv4 address assigned to the NIC.
+    :param subnet_mask: The subnet mask assigned to the NIC.
+    :param gateway: The default gateway IP address for forwarding network traffic to other networks.
+    :param mac_address: The MAC address of the NIC. Defaults to a randomly set MAC address.
+    :param speed: The speed of the NIC in Mbps.
+    :param mtu: The Maximum Transmission Unit (MTU) of the NIC in Bytes, representing the largest data packet size it
+        can handle without fragmentation.
+    :param wake_on_lan: Indicates if the NIC supports Wake-on-LAN functionality.
+    :param dns_servers: List of IP addresses of DNS servers used for name resolution.
+    :param connected_link: The link to which the NIC is connected (default is None).
+    :param enabled: Indicates whether the NIC is enabled.
+    """
+
+    ip_address: IPv4Address
+    "The IP address assigned to the NIC for communication on an IP-based network."
+    subnet_mask: str
+    "The subnet mask assigned to the NIC."
+    gateway: IPv4Address
+    "The default gateway IP address for forwarding network traffic to other networks. Randomly generated upon creation."
+    mac_address: str = generate_mac_address()
+    "The MAC address of the NIC. Defaults to a randomly set MAC address."
+    speed: Optional[int] = 100
+    "The speed of the NIC in Mbps. Default is 100 Mbps."
+    mtu: Optional[int] = 1500
+    "The Maximum Transmission Unit (MTU) of the NIC in Bytes. Default is 1500 B"
+    wake_on_lan: Optional[bool] = False
+    "Indicates if the NIC supports Wake-on-LAN functionality."
+    dns_servers: List[IPv4Address] = []
+    "List of IP addresses of DNS servers used for name resolution."
+    connected_link: Optional[Link] = None
+    "The Link to which the NIC is connected."
+    enabled: bool = False
+    "Indicates whether the NIC is enabled."
+
+    def connect_link(self, link: Link):
+        """
+        Connect the NIC to a link.
+
+        :param link: The link to which the NIC is connected.
+        :type link: :class:`~primaite.simulator.network.physical_layer.Link`
+        """
+        pass
+
+    def disconnect_link(self):
+        """Disconnect the NIC from the connected :class:`~primaite.simulator.network.physical_layer.Link`."""
+        pass
+
+    def add_dns_server(self, ip_address: IPv4Address):
+        """
+        Add a DNS server IP address.
+
+        :param ip_address: The IP address of the DNS server to be added.
+        :type ip_address: ipaddress.IPv4Address
+        """
+        pass
+
+    def remove_dns_server(self, ip_address: IPv4Address):
+        """
+        Remove a DNS server IP Address.
+
+        :param ip_address: The IP address of the DNS server to be removed.
+        :type ip_address: ipaddress.IPv4Address
+        """
+        pass
+
+    def send_frame(self, frame):
+        """
+        Send a network frame from the NIC to the connected link.
+
+        :param frame: The network frame to be sent.
+        :type frame: :class:`~primaite.simulator.network.osi_layers.Frame`
+        """
+        pass
+
+    def receive_frame(self, frame):
+        """
+        Receive a network frame from the connected link.
+
+        The Frame is passed to the Node.
+
+        :param frame: The network frame being received.
+        :type frame: :class:`~primaite.simulator.network.osi_layers.Frame`
+        """
+        pass
+
+    def describe_state(self) -> Dict:
+        """
+        Get the current state of the NIC as a dict.
+
+        :return: A dict containing the current state of the NIC.
+        """
+        pass
+
+    def apply_action(self, action: str):
+        """
+        Apply an action to the NIC.
+
+        :param action: The action to be applied.
+        :type action: str
+        """
+        pass
diff --git a/tests/unit_tests/primaite/simulator/__init__.py b/tests/unit_tests/_primaite/__init__.py
similarity index 100%
rename from tests/unit_tests/primaite/simulator/__init__.py
rename to tests/unit_tests/_primaite/__init__.py
diff --git a/tests/unit_tests/_primaite/_simulator/__init__.py b/tests/unit_tests/_primaite/_simulator/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/unit_tests/_primaite/_simulator/_network/__init__.py b/tests/unit_tests/_primaite/_simulator/_network/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/unit_tests/_primaite/_simulator/_network/test_physical_layer.py b/tests/unit_tests/_primaite/_simulator/_network/test_physical_layer.py
new file mode 100644
index 00000000..137e2cd6
--- /dev/null
+++ b/tests/unit_tests/_primaite/_simulator/_network/test_physical_layer.py
@@ -0,0 +1,26 @@
+import re
+
+import pytest
+
+from primaite.simulator.network.physical_layer import generate_mac_address
+
+
+def test_mac_address_generation():
+    """Tests random mac address generation."""
+    mac_address = generate_mac_address()
+    assert re.match("[0-9a-f]{2}([-:]?)[0-9a-f]{2}(\\1[0-9a-f]{2}){4}$", mac_address)
+
+
+def test_mac_address_with_oui():
+    """Tests random mac address generation with oui."""
+    oui = "aa:bb:cc"
+    mac_address = generate_mac_address(oui=oui)
+    assert re.match("[0-9a-f]{2}([-:]?)[0-9a-f]{2}(\\1[0-9a-f]{2}){4}$", mac_address)
+    assert mac_address[:8] == oui
+
+
+def test_invalid_oui_mac_address():
+    """Tests random mac address generation fails with invalid oui."""
+    invalid_oui = "aa-bb-cc"
+    with pytest.raises(ValueError):
+        generate_mac_address(oui=invalid_oui)
diff --git a/tests/unit_tests/primaite/simulator/test_core.py b/tests/unit_tests/_primaite/_simulator/test_core.py
similarity index 100%
rename from tests/unit_tests/primaite/simulator/test_core.py
rename to tests/unit_tests/_primaite/_simulator/test_core.py