  The sum-capacity of a three user interference wired network for time-varying
channels is considered. Due to the channel variations, it is assumed that the
transmitters are only able to track the connectivity between the individual
nodes, thus only the (alternating) state of the network is known. By
considering a special subset of all possible states, we show that state
splitting combined with joint encoding over the alternating states is required
to achieve the sum-capacity. Regarding upper bounds, we use a genie aided
approach to show the optimality of this scheme. This highlights that more
involved transmit strategies are required for characterizing the degrees of
freedom even if the transmitters have heavily restricted channel state
information.
