+WiFi platforms
+--------------
+
+In SimGrid, WiFi networks are modeled with WiFi zones, where a zone contains
+the access point of the WiFi network and the hosts connected to it (called
+station in the WiFi world). Links inside WiFi zones are modeled as regular
+links with a specific attribute, and these links are then added to routes
+between hosts. The main difference When using ns-3 WiFi networks is that
+the network performance is not given by the link bandwidth and latency but
+by the access point WiFi characteristics, and the distance between the access
+point and the hosts.
+
+So, to declare a new WiFi network, simply declare a zone with the ``WIFI``
+routing.
+
+.. code-block:: xml
+
+ <zone id="SSID_1" routing="WIFI">
+
+Inside this zone you must declare which host or router will be the access point
+of the WiFi network.
+
+.. code-block:: xml
+
+ <prop id="access_point" value="alice"/>
+
+Afterward simply declare the hosts and routers inside the WiFi network. Remember
+that one must have the same name as declared in the property "access point".
+
+.. code-block:: xml
+
+ <router id="alice" speed="1Gf"/>
+ <host id="STA0-0" speed="1Gf"/>
+ <host id="STA0-1" speed="1Gf"/>
+
+Finally, close the WiFi zone.
+
+.. code-block:: xml
+
+ </zone>
+
+The WiFi zone may be connected to another zone using a traditional link and
+a zoneRoute. Note that the connection between two zones is always wired.
+
+.. code-block:: xml
+
+ <link id="wireline" bandwidth="100Mbps" latency="2ms" sharing_policy="SHARED"/>
+
+ <zoneRoute src="SSID_1" dst="SSID_2" gw_src="alice" gw_dst="bob">
+ <link_ctn id="wireline"/>
+ </zoneRoute>
+
+WiFi network performance
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+
+The performance of a wifi network is controlled by 3 property that can be added
+to hosts connected to the wifi zone:
+
+ * ``mcs`` (`Modulation and Coding Scheme <https://en.wikipedia.org/wiki/Link_adaptation>`_)
+ Roughly speaking, it defines the speed at which the access point is
+ exchanging data with all stations. It depends on its model and configuration,
+ and the possible values are listed for example on Wikipedia.
+ |br| By default, ``mcs=3``.
+ It is a property of the WiFi zone.
+ * ``nss`` (Number of Spatial Streams, or `number of antennas <https://en.wikipedia.org/wiki/IEEE_802.11n-2009#Number_of_antennas>`_)
+ defines the amount of simultaneous data streams that the AP can sustain.
+ Not all value of MCS and NSS are valid nor compatible (cf. `802.11n standard <https://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_rates>`_).
+ |br| By default, ``nss=1``.
+ It is a property of the WiFi zone.
+ * ``wifi_distance`` is the distance from the station to the access point. Each
+ station can have a specific value.
+ |br| By default, ``wifi_distance=10``.
+ It is a property of stations of the WiFi network.
+
+Here is an example of a zone changing ``mcs`` and ``nss`` values.
+
+.. code-block:: xml
+
+ <zone id="SSID_1" routing="WIFI">
+ <prop id="access_point" value="alice"/>
+ <prop id="mcs" value="2"/>
+ <prop id="nss" value="2"/>
+ ...
+ </zone>
+
+Here is an example of a host changing ``wifi_distance`` value.
+
+.. code-block:: xml
+
+ <host id="STA0-0" speed="1Gf">
+ <prop id="wifi_distance" value="37"/>
+ </host>
+
+Random Number Generator
+=======================
+
+It is possible to define a fixed or random seed to the ns3 random number
+generator using the config tag.
+
+.. code-block:: xml
+
+ <?xml version='1.0'?><!DOCTYPE platform SYSTEM "https://simgrid.org/simgrid.dtd">
+ <platform version="4.1">
+ <config>
+ <prop id = "network/model" value = "ns-3" />
+ <prop id = "ns3/seed" value = "time" />
+ </config>
+ ...
+ </platform>
+
+The first property defines that this platform will be used with the ns3 model.
+The second property defines the seed that will be used. Defined to ``time``
+it will use a random seed, defined to a number it will use this number as
+the seed.
+