  We investigate the parameterized complexity of the following edge coloring
problem motivated by the problem of channel assignment in wireless networks.
For an integer q>1 and a graph G, the goal is to find a coloring of the edges
of G with the maximum number of colors such that every vertex of the graph sees
at most q colors. This problem is NP-hard for q>1, and has been well-studied
from the point of view of approximation. Our main focus is the case when q=2,
which is already theoretically intricate and practically relevant. We show
fixed-parameter tractable algorithms for both the standard and the dual
parameter, and for the latter problem, the result is based on a linear vertex
kernel.
