diff --git a/machines/models.py b/machines/models.py
index 4de0b012..f6168d37 100644
--- a/machines/models.py
+++ b/machines/models.py
@@ -397,7 +397,10 @@ class IpType(RevMixin, AclMixin, models.Model):
     @cached_property
     def complete_prefixv6(self):
         """Return the complete prefix v6 as cidr"""
-        return str(self.prefix_v6) + "/" + str(self.prefix_v6_length)
+        if self.prefix_v6:
+            return str(self.prefix_v6) + "/" + str(self.prefix_v6_length)
+        else:
+            return None
 
     def ip_objects(self):
         """ Renvoie tous les objets ipv4 relié à ce type"""
diff --git a/preferences/migrations/0051_optionalmachine_autocapture_iprange.py b/preferences/migrations/0051_optionalmachine_autocapture_iprange.py
new file mode 100644
index 00000000..df104d9b
--- /dev/null
+++ b/preferences/migrations/0051_optionalmachine_autocapture_iprange.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2018-08-31 14:37
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('machines', '0094_auto_20180815_1918'),
+        ('preferences', '0050_auto_20180818_1329'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='optionalmachine',
+            name='autocapture_iprange',
+            field=models.ManyToManyField(blank=True, help_text="Définit la plage d'ip depuis laquel un utilisateur peut enregistrer une machine filaire", to='machines.IpType'),
+        ),
+    ]
diff --git a/preferences/models.py b/preferences/models.py
index 3199dd6c..32de668e 100644
--- a/preferences/models.py
+++ b/preferences/models.py
@@ -149,6 +149,13 @@ class OptionalMachine(AclMixin, PreferencesModel):
         default=True
     )
 
+    autocapture_iprange = models.ManyToManyField(
+        'machines.IpType',
+        help_text=_("Définit la plage d'ip depuis laquel un utilisateur peut enregistrer une machine filaire"),
+        blank=True,
+    ) 
+
+
     @cached_property
     def ipv6(self):
         """ Check if the IPv6 option is activated """
diff --git a/preferences/templates/preferences/display_preferences.html b/preferences/templates/preferences/display_preferences.html
index 6a499969..6cb4c3a7 100644
--- a/preferences/templates/preferences/display_preferences.html
+++ b/preferences/templates/preferences/display_preferences.html
@@ -96,6 +96,11 @@ with this program; if not, write to the Free Software Foundation, Inc.,
         <tr>
             <th>{% trans "Creation of machines" %}</th>
             <td>{{ machineoptions.create_machine|tick }}</td>
+            <th>{% trans "IPs range d'autoregister" %}</th>
+            <td>{% for type in machineoptions.autocapture_iprange.all %}
+                    {{type.type}} 
+                {% endfor %} 
+                </td>
         </tr>
     </table>
     <h4>{% trans "Topology preferences" %}</h4>
diff --git a/users/views.py b/users/views.py
index 360e256b..b221f170 100644
--- a/users/views.py
+++ b/users/views.py
@@ -47,13 +47,14 @@ from django.http import HttpResponse
 from django.http import HttpResponseRedirect
 from django.views.decorators.csrf import csrf_exempt
 from django.utils.translation import ugettext as _
+from django.core.exceptions import PermissionDenied
 
 from rest_framework.renderers import JSONRenderer
 from reversion import revisions as reversion
 
 from cotisations.models import Facture, Paiement
 from machines.models import Machine
-from preferences.models import OptionalUser, GeneralOption, AssoOption
+from preferences.models import OptionalUser, OptionalMachine, GeneralOption, AssoOption
 from re2o.views import form
 from re2o.utils import (
     all_has_access,
@@ -71,6 +72,8 @@ from re2o.acl import (
 )
 from cotisations.utils import find_payment_method
 
+from netaddr import IPAddress, IPNetwork
+
 from .serializers import MailingSerializer, MailingMemberSerializer
 from .models import (
     User,
@@ -1084,27 +1087,31 @@ def process_passwd(request, req):
 
 @login_required
 def initial_register(request):
-    u_form = InitialRegisterForm(request.POST or None, user=request.user, switch_ip=request.GET.get('switch_ip', None), switch_port=request.GET.get('switch_port', None), client_mac=request.GET.get('client_mac', None))
-    if not u_form.fields:
-        messages.error(request, _("Incorrect URL, or already registered device"))
-        return redirect(reverse(
-            'users:profil',
-            kwargs={'userid': str(request.user.id)}
-        ))
-    if u_form.is_valid():
-        messages.success(request, _("Successful registration! Please"
-                                    " disconnect and reconnect your Ethernet"
-                                    " cable to get Internet access."))
+    options, created = OptionalMachine.objects.get_or_create()
+    if any(IPAddress(request.META['REMOTE_ADDR']) in t.ip_set for t in options.autocapture_iprange.all()) or any(IPAddress(request.META['REMOTE_ADDR']) in IPNetwork(t.complete_prefixv6) for t in options.autocapture_iprange.all() if t.complete_prefixv6 ):
+        u_form = InitialRegisterForm(request.POST or None, user=request.user, switch_ip=request.GET.get('switch_ip', None), switch_port=request.GET.get('switch_port', None), client_mac=request.GET.get('client_mac', None))
+        if not u_form.fields:
+            messages.error(request, _("Incorrect URL, or already registered device"))
+            return redirect(reverse(
+                'users:profil',
+                kwargs={'userid': str(request.user.id)}
+            ))
+        if u_form.is_valid():
+            messages.success(request, _("Successful registration! Please"
+                                        " disconnect and reconnect your Ethernet"
+                                        " cable to get Internet access."))
+            return form(
+                {},
+                'users/plugin_out.html',
+                request
+            )
         return form(
-            {},
-            'users/plugin_out.html',
+            {'userform': u_form, 'action_name': _("Register device or room")},
+            'users/user.html',
             request
         )
-    return form(
-        {'userform': u_form, 'action_name': _("Register device or room")},
-        'users/user.html',
-        request
-    )
+    else:
+        raise PermissionDenied
 
 
 class JSONResponse(HttpResponse):