Privacy Considerations

In some military and other sensitive environments, secure communications are required. The PBX firewall can determine if STU-III encrypted conversations are in process. If communications between two specific numbers are supposed to be always encrypted but are not, alerts can be sent or the calls can be terminated. Another potential privacy enhancement is the ability of two firewalls in separate locations to do end-to-end encryption.

EXHIBIT 1: Example policy setting screen. (Courtesy of SecureLogix, San Antonio, TX.)

For organizations requiring the highest levels of security, PBX firewalls may soon be able to perform word spotting. If, for example, the words "bomb" and "building" are used in a conversation, an alert could be sent to security. Obviously, there are many legal and ethical issues that must be resolved before such capabilities could be implemented, but with very fast chips and increasingly accurate voice recognition software such detection is possible.

Encrypted conversations have long been enabled by such devices as the telephone security device 3600, which use the STU-III government standard. The difficulty with this approach is that it does not scale. Any two users who want to encrypt information must have the same device and go through an encryption session at the beginning of the conversation. If many users need encryption, the solution becomes unwieldy and expensive because STU-III devices can cost several thousand dollars. With a PBX-to-PBX solution (i.e., both have PBX firewalls with encryption capabilities), every conversation from the users on one PBX to the other can be encrypted.

Security for PBXs is often convoluted. Rules may be set in one table but overridden in another.