Few think about inbound security. BYOD means allowing the most insecure devices in an organization to be carried through the doors, past the firewalls and into the heart of the corporate data vault, usually without more than a cursory virus scan or check of the onboard apps.
There are times or places even the least security conscious companies will want to ban cell phones, and not just to keep them from ringing during the CEO's speech.
Infected with malware or carried by an insider intent on stealing data, a cell phone provides an open data path to the outside, giving malware the chance to spread itself around to other phones, follow Wi-Fi signals to security-free entry to the corporate network, or letting hackers eavesdrop or launch attacks using remote-access tools.
Banning cell phones from certain areas and actually keeping them out are two different problems, however.
Unless you're willing to search every employee, contractor and visitor to a secure area, there's no way to be sure they're not carrying concealed, no matter how often you warn them their phones aren't welcome. Almost no adult with any sense of independence will voluntarily leave a cell phone behind just because someone else tells them to.
Childish as it seems to have to bust adults for carrying cell phones, sometimes it's necessary.
Fortunately there is a segment of the IT community that has been dealing with the danger of cell phones longer than the rest of us: those who work in high schools and are responsible for keeping students from cheating on big, standardized tests using apps, note-passing or Google searches to boost their GPA just a bit.
Berkeley Varitronics Systems, Inc. in Metuchen, N.J. sells a whole range of cell-phone detectors that could fill the need, the newest and smallest of which is the $500 PocketHound which, at six ounces and a bulk about the same as a pack of cards, is smaller than many of the phones it detects.
PocketHound can detect cell phones at a range of about 75 feet, whether they're in use or not by reading the radio-frequency signals they send out even at rest.
It covers all U.S. and international bands of PCS, CDMA/WCDMA, UMTS, GSM, EGSM, lets users pick the bands they'll scan for and dial the sensitivity up or down to avoid false positives.
It can signal by flashing LEDs or making noise and automatically sets its alert threshold high enough to avoid ambient RF noise already in the room.
BVS bills it as "Perfect for cheating students, corporate espionage, courtroom and prisons too."