The Chicago Fire Department lately has experienced a series of incidents that many emergency services experts agree is rather unusual: a hacker, apparently using a non-official radio, has been spewing racial epithets over the fire band.

To solve the problem, the city has reprogrammed all 1400-plus of its fire radios to identify them as city property, which ostensibly will prevent the transmission of rogue broadcasts. It also has begun a previously announced migration to a new $180 million citywide digital trunking system. The $10 million first phase, to be executed later this year, will cover the fire department and make this kind of activity a near impossibility, according to sources.

The headache began in February when a firefighter on the way to an emergency situation used a racial epithet to describe a driver who was impeding traffic. The remark was unintentionally broadcast and the firefighter was disciplined, but the incident sparked what the CFD believes is at least one copycat who has spewed racial remarks over the air on several subsequent occasions.

“We're 99% sure [this is coming from outside the 5000-member fire department] but we don't know who's operating the radios,” said Larry Langford, a spokesman for Emergency Management and Communications who also happens to be a radio frequency engineer.

When it was first deployed, Chicago's emergency communications system was “not designed for security, it was designed for efficiency,” Langford said, and didn't have private line continuous tone squelch [PL] detection. When the city eventually added PL, it was to block out drift from radios in places such as Milwaukee and Indianapolis; it wasn't a security measure.

The addition of PL created a breach point, according to Langford.

“You can get in if you have the PL and the frequency of the input,” said Langford. “The PL tone, you can get that off the air and figure out what it is; it's not any form of encryption, it's just a way to manage the channel a little better in congestion situations.”

While it's possible that someone has cracked that code, it's also possible, say industry experts, that someone simply is using a stolen or discarded radio.

“That's not uncommon,” said Garry Briese, executive director of the International Association of Fire Chiefs. “To intentionally hack into the frequency is uncommon; in fact, it's the very first time I've heard about it happening.”

Harlin McEwen, chairman of the International Association of Chiefs of Police [IACP] Communications & Technology Committee, agreed it is unlikely an outsider had learned the codes and set up a radio to break into the airwaves.

“It takes a bit of an effort. You can't just go to the store and buy a radio that will do this,” he said. “In all my years it has been my experience that we've had hardly any problem with outside people getting into the system and causing interference intentionally.” However, McEwen acknowledged the older analog technology prevents anyone from being sure where the signals are emanating.

The nonsense will certainly stop later this year when the department migrates to the digital trunked system, said Chuck Jackson, vice president and director of system operations for Motorola, which builds the Chicago equipment. While the legacy analog system resembles a telephone party line — everyone can join the conversation — the new system recognizes the caller and assigns a trunked channel, according to Jackson.

“As soon as you key your radio, it comes up on a computer screen as exactly what radio it is — the actual handset or the actual mobile radio — each has a unique identifier,” he said.

Jackson added the digital trunked system wouldn't complete a transmission unless all users along the communications path are authorized.

“You push a button and in less than a quarter of a second the digital messages go back and check to make sure that you're authorized in the database,” he said.

That would make it nearly impossible for a rogue radio to disrupt communications. “We don't even talk about this with the new technology; [the security is] just built in, part of the technology,” Jackson said.

McEwen agreed the digital trunked system would provide the ultimate solution. “It will give them the tools to be able to control and manage this kind of problem,” he said.

In the meantime, the recently completed analog radio reprogramming represents a bridge strategy that will enable the system to reject any radio that doesn't have the proper ID. “We're changing it around so the system will ask the radio if it has an ID and if the radio does not present an ID, the system will not respond to it,” said Langford.

Considering the technology at hand, that's about as good as it's going to get for the moment, he added.

“It's not some super encryption or anything; it's just what we can do with the system as it stands now,” he said. “When we migrate the system off VFH to T [trunked] band, each radio will be addressable, and if somebody steals a radio we can turn it off and make the system blind to it.”

Accidents Do Happen

While deliberate acts such as spewing racial epithets over the Chicago Fire Department airwaves are unusual, accidental interference with emergency radio operations does happen.

Vincent Stile, president of the Association of Public-Safety Communications Officials International [APCO] and director of radio communications for the Suffolk County, N.Y., police department, recalled an incident several years ago in the New York City suburbs where “one of the police departments was being interfered with or somebody was getting into them illegally.”

Turned out it was a taxi company. Stile, with the help of a local radio shop that listened in on the interference, winnowed down the possibilities and alerted law enforcement agencies.

“I don't think the interference was done intentionally, it was an accident. They were on the frequency and didn't realize it,” Stile said.

Nevertheless, what was going on was “illegal as hell” and the police took measures to make sure it stopped.

“Nassau County police and Garden City (N.Y.) police went in and found these guys,” he said. “It must have been interesting. They went in and confiscated all the equipment. I wish I could have been there.”
— Jim Barthold