+**Option** ``network/latency-factor`` **Default:** 1.0, but overridden by most models
+
+This option specifies a multiplier to apply to the *physical* latency (i.e., the one described in the platform) of the set of
+links involved in a communication. The factor can either be a constant to apply to any communication, or it may depend on the
+message size. The ``CM02`` model does not use any correction factor, so the latency-factor remains to 1. The ``LV08`` model sets
+it to 13.01 to model slow-start, while the ``SMPI`` model has several possible values depending on the interval in which the
+message size falls. The default SMPI setting given below specifies for example that a message smaller than 257 bytes will get a
+latency multiplier of 2.01467 while a message whose size is in [15424, 65472] will get a latency multiplier of 3.48845. The
+``wifi`` model goes further and uses a callback in the program to compute the factor that must be non-linear in this case.
+
+This multiplier is applied to the latency computed from the platform, that is the sum of all link *physical* latencies over the
+:ref:`network path <platform_routing>` used by the considered communication, to derive the *effective* end-to-end latency.
+
+Constant factors are easy to express, but the interval-based syntax used in SMPI is somewhat complex. It expects a set of
+factors separated by semicolons, each of the form ``boundary:factor``. For example if your specification is
+``0:1;1000:2;5000:3``, it means that on [0, 1000) the factor is 1. On [1000,5000), the factor is 2 while the factor is 3 for
+5000 and beyond. If your first interval does include size=0, then the default value of 1 is used before. Changing the factor
+callback is not possible from the command line and must be done from your code, as shown in `this example
+<https://framagit.org/simgrid/simgrid/tree/master/examples/cpp/network-factors/s4u-network-factors.cpp>`_. Note that the chosen
+model only provides some default settings. You may pick a ``LV08`` model to get some of the settings, and override the latency
+with interval-based values.
+
+SMPI default value: 65472:11.6436; 15424:3.48845; 9376:2.59299; 5776:2.18796; 3484:1.88101; 1426:1.61075; 732:1.9503;
+257:1.95341;0:2.01467 (interval boundaries are sorted automatically). These values were computed by data fitting on the Stampede
+Supercomputer at TACC, with optimal deployment of processes on nodes. To accurately model your settings, you should redo the
+:ref:`calibration <models_calibration>`.
+
+**Option** ``network/bandwidth-factor`` **Default:** 1.0, but overridden by most models
+
+Setting this option automatically adjusts the *effective* bandwidth (i.e., the one perceived by the application) used by any
+given communication. As with latency-factor above, the value can be a constant (``CM02`` uses 1 -- no correction -- while
+``LV08`` uses 0.97 to discount TCP headers while computing the payload bandwidth), interval-based (as the default provided by
+the ``SMPI``), or using in-program callbacks (as with ``wifi``).
+
+SMPI default value: 65472:0.940694;15424:0.697866;9376:0.58729;5776:1.08739;3484:0.77493;1426:0.608902;732:0.341987;257:0.338112;0:0.812084
+This was also computed on the Stampede Supercomputer.
+
+**Option** ``network/weight-S`` **Default:** depends on the model
+
+Value used to account for RTT-unfairness when sharing a bottleneck (network connections with a large RTT are generally penalized
+against those with a small one). See :ref:`models_TCP` and also this scientific paper: `Accuracy Study and Improvement of Network
+Simulation in the SimGrid Framework <http://mescal.imag.fr/membres/arnaud.legrand/articles/simutools09.pdf>`_
+
+Default values for ``CM02`` is 0. ``LV08`` sets it to 20537 while both ``SMPI`` and ``IB`` set it to 8775.
+
+.. _cfg=network/loopback:
+
+Configuring loopback link
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Several network models provide an implicit loopback link to account for local
+communication on a host. By default it has a 10GBps bandwidth and a null latency.
+This can be changed with ``network/loopback-lat`` and ``network/loopback-bw``
+items. Note that this loopback is conveniently modeled with a :ref:`single FATPIPE link <pf_loopback>`
+for the whole platform. If modeling contention inside nodes is important then you should
+rather add such loopback links (one for each host) yourself.
+
+.. _cfg=smpi/IB-penalty-factors:
+
+Infiniband model
+^^^^^^^^^^^^^^^^