diff --git a/13_api_key.md b/13_api_key.md
new file mode 100644
index 0000000..c643135
--- /dev/null
+++ b/13_api_key.md
@@ -0,0 +1,95 @@
+# API-Key
+
+## Validation using Nginx only
+
+A very simple example to validate api keys directly via Nginx
+
+```bash
+cd /etc/nginx/conf.d/
+sudo vi myKeys.conf
+```
+
+define valid keys:
+
+```nginx
+# validating the header "Authorization"
+map $http_authorization $api_client_name {
+    default       "";       # no key matches
+    "key_aaaaaa"  "client_a";
+    "key_bbbbbb"  "client_b";
+}
+```
+
+and perform validation within Nginx site configuration:
+
+```nginx
+location /api/auth/names {
+        # if empty, no key was found
+        if ($api_client_name = "") {
+            return 401 '{"error": "Ungültiger oder fehlender API-Key"}';
+        }
+
+        # Optional: forward user to backend (using header: X-Matched-Client)
+        proxy_set_header X-Auth-User $api_client_name;
+
+        proxy_pass http://127.0.0.1:5000/names;
+}
+```
+
+Verify with Postman.
+
+## Validation via Auth-Modul
+
+integrate to webservice source code:
+
+```python
+from flask import Flask, jsonify, request, Response
+
+API_KEYS = {
+    "key_cccccc": "User-C",
+    "key_dddddd": "User-D"
+}
+
+@app.route('/validate', methods=['GET'])
+def validate():
+    api_key = request.headers.get('Authorization')
+
+    if not api_key:
+        return Response("Missing API Key", status=401)
+
+    client_name = API_KEYS.get(api_key)
+
+    if client_name:
+        res = Response("Valid", status=200)
+        res.headers['X-Auth-User'] = client_name
+        return res
+
+    return Response("Invalid API Key", status=401)
+```
+
+and add to nginx site configuration:
+
+```nginx
+location = /_auth_check {
+        internal; # nginx internal requests only
+        proxy_pass http://localhost:5000/validate; # Auth-Modul
+
+        # skip body
+        proxy_pass_request_body off;
+        proxy_set_header Content-Length "";
+
+        # pass key to auth-service
+        proxy_set_header X-Original-URI $request_uri;
+        proxy_set_header Authorization $http_authorization;
+}
+
+location = /api/auth2/names {
+        # perform request towards Auth-Service
+        auth_request /_auth_check;
+
+        # in case of 200 OK Nginx continues
+        proxy_pass http://127.0.0.1:5000/names;
+}
+```
+
+Verify with Postman.
\ No newline at end of file
diff --git a/14_enable_http_2_http_3.md b/14_enable_http_2_http_3.md
new file mode 100644
index 0000000..bbf6506
--- /dev/null
+++ b/14_enable_http_2_http_3.md
@@ -0,0 +1,37 @@
+# Enable HTTP/2 in Nginx
+
+following adaption of the nginx site config is needed (nginx version > 1.25.1):
+
+```nginx
+listen 443 ssl;
+http2 on;
+```
+for older nginx-versions:
+
+```nginx
+listen 443 ssl http2;
+```
+
+verify via browser debug console.
+
+# Enable HTTP/3 (QUIC) in Nginx
+
+## verify nginx version
+Nginx supports HTTP/3 starting with version 1.25.0.
+
+```bash
+sudo nginx -v
+```
+
+## enable http/3
+
+```nginx
+# Port 443 using UDP (HTTP/3)
+listen 443 quic reuseport;
+listen [::]:443 quic reuseport;
+
+# inform browser, we support HTTP/3
+add_header Alt-Svc 'h3=":443"; ma=86400';
+
+http3 on; # optional. http/3 will enabled also without this setting
+```