+\subsubsection options_pls Configuring packet-level pseudo-models
+
+When using the packet-level pseudo-models, several specific
+configuration flags are provided to configure the associated tools.
+There is by far not enough such SimGrid flags to cover every aspects
+of the associated tools, since we only added the variables that we
+needed ourselves. Feel free to request more variables (or even better:
+provide patches adding more variables).
+
+When using NS3, the only existing variable is \b ns3/TcpModel,
+corresponding to the ns3::TcpL4Protocol::SocketType configuration item
+in NS3. The only valid values (enforced on the SimGrid side) are
+'NewReno' or 'Reno' or 'Tahoe'.
+
+When using GTNeTS, two variables exist:
+ - \b gtnets/jitter, that is a double value to oscillate
+ the link latency, uniformly in random interval
+ [-latency*gtnets_jitter,latency*gtnets_jitter). It defaults to 0.
+ - \b gtnets/jitter_seed, the positive seed used to reproduce jitted
+ results. Its value must be in [1,1e8] and defaults to 10.
+