xbt::signal<void(Link const&)> Link::on_bandwidth_change;
xbt::signal<void(kernel::resource::NetworkAction&, kernel::resource::Action::State)>
Link::on_communication_state_change;
xbt::signal<void(Link const&)> Link::on_bandwidth_change;
xbt::signal<void(kernel::resource::NetworkAction&, kernel::resource::Action::State)>
Link::on_communication_state_change;