Ciena Corporation is an American telecommunications networking equipment and software services supplier based in Hanover, Maryland. The company has been described by The Baltimore Sun as the "world's biggest player in optical connectivity." The company reported revenues of $3.57 billion for 2019. Ciena has approximately 6,000 employees, as of October 2018. Gary Smith serves as president and chief executive officer. Customers include AT&T, Deutsche Telekom, Korea Telecom, Sprint Corporation, and Verizon Communications.