Analysis, Review and Optimization of SONET/SDH Technology for today and   future aspects
  Network layers are analyzed for their design and issues of researches, while dense wavelength division multiplexing equipment has been deployed in networks of major telecommunications carriers for a long time, the efficiency of networking and relation with network control and management have not caught up to those of digital cross-connect systems and packet-switched counterparts in higher layer networks. 
Gourav Verma, Deepika Ramaiya
cs.NI