Comcast (Nasdaq: CMCSA) is the latest service provider to see how 1 Tbps optical transmission could work over a live network. The cable MSO, reports FierceCable, recently completed a live field trial of a 1 Tbps long-haul transmission network that spans nearly 1,000 km connecting Ashburn, Va., to Charlotte, N.C. During the trial, Comcast used Ciena's (Nasdaq: CIEN) 6500 packet-optical platform, which combined flexible grid reconfigurable optical add/drop multiplexers with 16 QAM coherent modulation to achieve 5 b/s/Hz of special efficiency over the 1,000 KM distance. Read more