namespace kernel {
namespace routing {
+/** @ingroup ROUTING_API
+ * @brief NetZone where each component is connected through a private link
+ *
+ * Cluster zones have a collection of private links that interconnect their components.
+ * This is particularly well adapted to model a collection of elements interconnected
+ * through a hub or a through a switch.
+ *
+ * In a cluster, each component are given from 1 to 3 private links at creation:
+ * - Private link (mandatory): link connecting the component to the cluster core.
+ * - Limiter (optional): Additional link on the way from the component to the cluster core
+ * - Loopback (optional): non-shared link connecting the component to itself.
+ *
+ * Then, the cluster core may be constituted of a specific backbone link or not;
+ * A backbone can easily represent a network connected in a Hub.
+ * If you want to model a switch, either don't use a backbone at all,
+ * or use a fatpipe link (non-shared link) to represent the switch backplane.
+ *
+ * \verbatim
+ * (outer world)
+ * |
+ * ======+====== <--backbone
+ * | | | |
+ * l0| l1| l2| l4| <-- private links + limiters
+ * | | | |
+ * X X X X <-- cluster's hosts
+ * \endverbatim
+ *
+ * \verbatim
+ * (outer world)
+ * | <-- NO backbone
+ * /|\
+ * / | \ <-- private links + limiters __________
+ * / | \
+ * l0 / l1| \l2
+ * / | \
+ * host0 host1 host2
+ * \endverbatim
+
+ * So, a communication from an host A to an host B goes through the following links (if they exist):
+ * <tt>limiter(A)_UP, private(A)_UP, backbone, private(B)_DOWN, limiter(B)_DOWN.</tt>
+ * link_UP and link_DOWN usually share the exact same characteristics, but their
+ * performance are not shared, to model the fact that TCP links are full-duplex.
+ *
+ * A cluster is connected to the outer world through a router that is connected
+ * directly to the cluster's backbone (no private link).
+ *
+ * A communication from an host A to the outer world goes through the following links:
+ * <tt>limiter(A)_UP, private(A)_UP, backbone</tt>
+ * (because the private router is directly connected to the cluster core).
+ */
+
class XBT_PRIVATE ClusterZone : public NetZoneImpl {
public:
explicit ClusterZone(NetZone* father, const char* name);
