diff --git a/src/knx/secure_application_layer.h b/src/knx/secure_application_layer.h
index 2e7270e..60684eb 100644
--- a/src/knx/secure_application_layer.h
+++ b/src/knx/secure_application_layer.h
@@ -5,6 +5,7 @@
 #include "knx_types.h"
 #include "apdu.h"
 #include "bits.h"
+#include "simple_map.h"
 
 class DeviceObject;
 class SecurityInterfaceObject;
@@ -60,127 +61,6 @@ class SecureApplicationLayer :  public ApplicationLayer
 
   private:
 
-    template <typename K, typename V, int SIZE>
-    class Map
-    {
-    public:
-        Map()
-        {
-            static_assert (SIZE <= 64, "Map is too big! Max. 64 elements.");
-        }
-
-        void clear()
-        {
-            _validEntries = 0;
-        }
-
-        bool empty()
-        {
-            return (_validEntries == 0);
-        }
-
-        uint8_t size()
-        {
-            uint8_t size = 0;
-
-            for (uint8_t i = 0; i < SIZE; i++)
-            {
-                size += (((_validEntries >> i) & 0x01) == 0x01) ? 1 : 0;
-            }
-
-            return size;
-        }
-
-        bool insert(K key, V value)
-        {
-            uint8_t index = getNextFreeIndex();
-            if (index != noFreeEntryFoundIndex)
-            {
-                keys[index] = key;
-                values[index] = value;
-
-                _validEntries |= 1 << index;
-                return true;
-            }
-
-            // No free space
-            return false;
-        }
-
-        bool insertOrAssign(K key, V value)
-        {
-            // Try to find the key
-            for (uint8_t i = 0; i < SIZE; i++)
-            {
-                // Check if this array slot is occupied
-                if ((_validEntries >> i) & 0x01)
-                {
-                    // Key found?
-                    if (keys[i] == key)
-                    {
-                        values[i] = value;
-                        return true;
-                    }
-                }
-            }
-
-            // Key does not exist, add it if enough space
-            return insert(key, value);
-        }
-
-        bool erase(K key)
-        {
-            for (uint8_t i = 0; i < SIZE; i++)
-            {
-                if ((_validEntries >> i) & 0x01)
-                {
-                    if (keys[i] == key)
-                    {
-                        _validEntries &= ~(1 << i);
-                        return true;
-                    }
-                }
-            }
-            return false;
-        }
-
-        V* get(K key)
-        {
-            // Try to find the key
-            for (uint8_t i = 0; i < SIZE; i++)
-            {
-                // Check if this array slot is occupied
-                if ((_validEntries >> i) & 0x01)
-                {
-                    // Key found?
-                    if (keys[i] == key)
-                    {
-                        return &values[i];
-                    }
-                }
-            }
-            return nullptr;
-        }
-
-    private:
-        uint8_t getNextFreeIndex()
-        {
-            for (uint8_t i = 0; i < SIZE; i++)
-            {
-                if (((_validEntries >> i) & 0x01) == 0)
-                {
-                    return i;
-                }
-            }
-
-            return noFreeEntryFoundIndex;
-        }
-
-        uint64_t _validEntries{0};
-        K keys[SIZE];
-        V values[SIZE];
-        static constexpr uint8_t noFreeEntryFoundIndex = 255;
-    };
 
     enum class AddrType : uint8_t
     {