He is a Program Director in the Computer & Network Systems (CNS) Division at the National Science Foundation (NSF).

[1] He worked as Curators' Distinguished Professor in the department of computer science and electrical engineering at the University of Missouri–Kansas City.

[4][5][6] Prior to joining the University of Missouri–Kansas City, he worked as a technical officer at AT&T Bell Laboratories, routing and designing teletraffic networks.

[7] While at AT&T Bell Laboratories, he co-invented the Facility Diverse Routing system.

[7] He is currently working as a program director in the computer and network systems (CNS) division of the National Science Foundation (NSF) in the United States.