Catching the Bad Guys (Part 1)

This is one of those columns that necessarily dips into the anxious language of current events: Tracking the phone activities of the bad guys.

It's about CALEA, which stands for the Communications Assistance for Law Enforcement Act.

CALEA, usually pronounced as a word, "kuh-LEE-uh," is an effort to electronically monitor and track the telephone activities of suspected criminals. As its last word denotes — "Act" — it is a law, enacted in 1994.

In these times, and particularly since the rise of terrorist threats, there's ample reason for institutions like the FBI, as well as local police agencies, to need help from service providers – including those cable operators who also offer telephone lines to customers.

Court orders

If you've not heard of CALEA — and you're either doing or getting ready to do phone service over cable, whether circuit-switched or Internet protocol-based — you need to be ready. This is the kind of thing where a uniformed police officer shows up at the GM's doorstep, court order in hand.

The court order usually requires immediate access to the phone records and conversations of a customer, who is a suspect, for whatever reason, in a criminal activity.

The immediacy is reflected in the wording of the law itself, which makes frequent use of the word "expeditiously," especially at the front of sentences. Telling the uniformed police officer with the court order that you'll need three days to get the CALEA gear set up is just as helpful as telling the firefighter that you'll need three days to get that bucket of water.

CALEA came to be because it is no longer enough to gaff a telephone pole a few blocks from a suspect's location, clamp onto a pair of phone wires and listen in. If anything has flourished in the history of electronics, it is our collective appetite for talking with each other. The marketplace responded. The result is an increasingly complex environment in which the good guys must catch the bad guys.

Modules help

At the head-scratching boundaries of electronic surveillance are devices like the disposable cellular phone, bought with cash. In between are alternate forms of telephone communications, like PC-based IP phone, cable phone, and anything else that allows people to use traditionally unmonitored lines of communication.

Because the need for electronic surveillance has long roots — wiretaps have been around for decades — the existing circuit-switched forms of telephone communications come with CALEA modules. That makes getting ready for CALEA more straightforward for cable operators who offer circuit-switched telephony.

In that scenario, enacting a CALEA event involves sending a specifically entrusted cable employee to the circuit switch, invoking the CALEA software and setting up the spigot that flows the necessary information to the FBI or police.

Two things are required: Call data and call content. Call data is everything that can happen with a phone: What numbers it dials, what numbers it receives. Details of three-way calling events or call-forwarding activities. Call content is the equivalent of slipping another straw into the drink: It taps the call.

That information is collected and sent to law enforcement officials over protocols specified in CALEA.

Gathering call detail and content in a packet-based, IP environment isn't quite as straightforward. A voice call made over the public Internet uses the methods of the Internet, which break a bunch of packets into clumps and send them, over varying routes, to their destination. The route can change from one call to the next.

The industry's specifications for voice-over-IP, known collectively as PacketCable, include methods for dealing with CALEA.

All vendors of VoIP equipment for cable are aware of CALEA, and offer modules or stand-alone servers to address the need for electronic surveillance. But, because VoIP over cable is still relatively new, it's fair to say that its CALEA efforts have yet to settle into a pattern.

Some suppliers, for example, combine CALEA directly into a softswitch. Others isolate CALEA into a separate server. PacketCable allows for integrated or stand-alone handling.

What works in a day-to-day environment will work itself out as everything else related to the VoIP back office works itself out.

That's the set-up of CALEA, and its importance in cable's growing presence as a telephone service provider.

Next time, a look at how information flows to and from law enforcement agencies in VoIP environments.

Questions? Suggestions? E-mail Leslie Ellis at