Phil Zimmermann, initial programmer of “PGP”—Pretty Good Privacy—brought strong encryption to the masses. For three years ending in 1996, Zimmermann was under criminal investigation for violating export restrictions on strong encryption due to his work on PGP. Furthermore, PGP was not free software for everyone, only for those in non-profit organizations. Eventually GPG—the GNU Privacy Guard—was written by a completely different group of hackers and we no longer had to do without strong encryption or choose between giving up valuable freedoms in exchange for enjoying strong encryption.

Now Zimmermann has distributed Zfone, a program much like the PGPfone program years ago: encrypted voice communication in real time over the Internet. But there’s a huge catch: you give up a lot to get the software or (according to what the license tries to assert) use it. I only followed the registration procedure long enough to read the license, portions of which I quote below.

The Zfone software can only be copied “a reasonable number” (section 1a) of times, one is not allowed to make the software do what the user needs it to do (section 2a disallows modifications not specified in section 1), and one is disallowed from copying the software beyond what is described in section 1 (section 2b). Sections 2d and 2f prohibit sharing copies of the source code except in one circumstance.

Section 2e of Zfone’s license tries to set restrictions for merely running the compiled program (something the FSF once said couldn’t be done under American copyright law outside of a license manager or an encryption manager).

Section 3 of Zfone’s license tries to prohibit users from discussing “any security-related bug, problem, deficiency, or weakness in the Zfone software on any web site or other public forum, or otherwise disclose or provide any such information to anyone else” without Zimmermann’s permission.

Unlike PGP which at one time was considered semi-free software because it didn’t convey the freedoms to use, copy, distribute, and modify the program to all of its users, this program’s license tries to curtail one’s freedom of speech in addition to taking away one’s software freedom. Ironic that this should come from the man who was once under criminal investigation by the US Government (a time he refers to as “government persecution” on his website) in which he probably felt the loss of his civil liberties. I very much doubt that Zfone’s software would qualify as semi-free software. Zfone should be avoided. Instead it would be better to enhance free software VOIP (such as Ekiga) to do the job of sending and receiving strongly encrypted data, and making free software VOIP programs compatible with Zfone so that interoperability is possible without giving up valuable freedoms.