:language: xml
The root tag must be ``<platform>``, and its ``version`` attribute
-specifies the used DTD version. When the DTD evolutions introduce
+specifies which version of the DTD is use. When an evolution of the DTD introduces
backward-incompatible changes, this number gets updated. Use the
``simgrid_update_xml`` utility to upgrade your platform files on need.
-
Then, every platform element must be located within a given
**networking zone** introduced with the :ref:`pf_tag_zone` tag. Zones
-are in charge of the routing: an host wants to communicate with
-another host of the same zone, it is the zone's duty to find the list
+are in charge of the routing. If a host wants to communicate with
+another host belonging to the same zone, it is the zone's duty to find the list
of links that are involved in the communication. Here, since we use
``routing="Full"``, all routes must be explicitly given using the
:ref:`pf_tag_route` and :ref:`pf_tag_linkctn` tags (this :ref:`routing
model <pf_rm>` is both simple and inefficient :) It is OK to not
-specify each and every route between hosts, as long as you don't start
-at runtime any communications on the missing routes.
-
-Any zone may contain sub-zones itself, leading to a hierarchical
-decomposition of the platform. This can be more efficient (as the
-inter-zone routing gets factorized with :ref:`pf_tag_zoneroute`), and
-allows to have more than one routing model in your platform. For
-example, you could have a coordinate-based routing for the WAN parts
+specify each and every route between hosts, as long as you do not try to start
+a communication on any of the missing routes during your simulation.
+
+Any zone may contain sub-zones, allowing for a hierarchical
+decomposition of the platform. Routing can be made more efficient (as the
+inter-zone routing gets factored with :ref:`pf_tag_zoneroute`), and
+allows you to have more than one routing model in your platform. For
+example, you can have a coordinate-based routing for the WAN parts
of your platforms, a full routing within each datacenter, and a highly
optimized routing within each cluster of the datacenter. In this
-case, determining the route between two given hosts gets @ref
-routing_basics "somewhat more complex" but SimGrid still computes
+case, determining the route between two given hosts gets :ref:`routing_basics`
+"somewhat more complex" but SimGrid still computes
these routes for you in a time- and space-efficient manner.
Here is an illustration of these concepts:
subset of a LAN (AS6), and a set of peers scattered around the world
(AS7).
-.. todo:: Add more examples, such as the cloud example descibed in
- previous paragraph
-
+.. todo:: Add more examples, such as the cloud example described in
+ previous paragraph
+