The process in which a signal is passed on to downstream components within the cell through the NIK-dependent processing and activation of NF-KappaB. The cascade begins with activation of the NF-KappaB-inducing kinase (NIK), which in turn phosphorylates and activates IkappaB kinase alpha (IKKalpha). IKKalpha phosphorylates the NF-Kappa B2 protein (p100) leading to p100 processing and release of an active NF-KappaB (p52).