Lightpath, the business telecommunications services division of Cablevision Systems, has deployed a DWDM metro optical transport solution from Nortel Networks. Lightpath, which is the third largest LEC in New York state, is using Nortel Networks OPTera Metro 5200 Multiservice Platform to evolve its existing SONET-based infrastructure to deliver metro Ethernet, SAN, and other managed services. Financial terms were not disclosed.