Visitors to Terminal B at Newark Liberty International Airport may notice the bright, clean lighting that now blankets the cavernous interior, courtesy of 171 recently installed LED fixtures. But they probably will not realize that the light fixtures are the backbone of a system that is watching them.

Using an array of sensors and eight video cameras around the terminal, the light fixtures are part of a new wireless network that collects and feeds data into software that can spot long lines, recognize license plates and even identify suspicious activity, sending alerts to the appropriate staff.

The project is still in its early stages, but executives with the Port Authority of New York and New Jersey, which operates the airport, are already talking about expanding it to other terminals and buildings.

To customers like the Port Authority, the systems hold the promise of better management of security as well as energy, traffic and people. But they also raise the specter of technology racing ahead of the ability to harness it, running risks of invading privacy and mismanaging information, privacy advocates say.