Reporting Bugs

Zfone is a new secure VoIP phone software package which lets you make secure encrypted phone calls over the Internet. To learn about the right way to install and test Zfone, visit the Getting Started with Zfone page.

Skip further down after the bug reporting section for information about known bugs and other issues.

Reporting Bugs in the Zfone Public Beta

Please help us make Zfone better for everyone by taking the time to report bugs, and give us as much detail you can to help us track down the problem and fix it.

To report a bug, select Create Bug Report in the Zfone Help menu, which creates a compressed bug report log file on your Desktop, called zfone-bug-report-(date). This file should be emailed as an attachment, along with a detailed description of the bug, to our development team at bug-reports at zfoneproject dot com.

Please use the bug-reports email address only to report bugs or problems you are having with the software, because it goes to the developers who fix bugs. If you want to send email for other reasons, see our contact page.

Be sure to specify everything in the bug report, such as:

The exact circumstances of the bug, and whether and how the bug can be reproduced, in detail (our engineers will not read a bug report that only includes the zfone-bug-report log file, if you don't bother to include some text describing the bug).
What VoIP client (and version number of the VoIP client) you were using,
what operating system (and the exact version of the operating system) you ran it on (Windows XP, Mac OS X, Linux),
anything else that we should know.
The most important thing to include-- the zfone-bug-report log file produced by the "Create bug report" command in the Zfone Help menu. We really need to see the log files from both parties, so please create and send bug reports from both sides of the conversation.

For the free public beta of Zfone, bug reports are encouraged, but requests for support will likely get no response. If you want support, you'll have to wait for the official release and pay for it.

Things you should know before you report bugs

A word about how Zfone uses this protocol

The ZRTP protocol used by Zfone will soon be integrated into many standalone secure VoIP clients, and that is the most effective way to use the protocol. But the Zfone application is not itself a VoIP client, and uses the ZRTP protocol differently. Zfone lets you turn your existing VoIP client into a secure phone, by passing the VoIP packets through a separate encryption filter outside of the VoIP client. The Zfone software runs in the Internet protocol stack on any Windows XP, Mac OS X, or Linux PC, and intercepts and filters all the VoIP packets as they go in and out of the machine, and secures the call on the fly. You can use a variety of different software VoIP clients to make a VoIP call. The Zfone software detects when the call starts, and initiates a cryptographic key agreement between the two parties, and then proceeds to encrypt and decrypt the voice packets. It has its own little separate GUI, telling the user if the call is secure. It's as if Zfone were a "bump on the wire", sitting between the VoIP client and the Internet. Think of it as a bump in the protocol stack. We're explaining this packet fitering aspect of Zfone here because some bugs may be related to it.

Don't blame Zfone for your VoIP client problems

Many things can go wrong with VoIP client software. There could be problems with your firewall, with getting VoIP calls to traverse your local network's NAT router, with your audio configuration choices (especially your microphone), with your VoIP service provider. For this reason, it is important that you get your VoIP client tested and working before you install Zfone. We don't want to get emails from you complaining that Zfone doesn't work, when you haven't first established that your VoIP client works in your local network environment.

Windows users must not interrupt the installation process!

We warned you about this earlier on the Getting Started with Zfone page and then we warned you again on the download page for the Windows version, but it bears repeating here: Windows users should not interrupt the installation process, despite multiple warnings stating that the ZRTP Miniport driver is not Windows Logo certified. If you interrupt the installation, there will be various harmful effects, including crashing the system. It's dangerous to interrupt the installation of any device driver on Windows, including this one.

If Zfone for Windows crashes, you can always use the Windows Recovery Console to roll back all changes caused by installing Zfone. For additional information see:

Note that Zfone runs on the 32-bit version of Windows XP, but not the 64-bit version, and also not on Vista. We do plan to support 64-bit Windows XP Pro in a future release.

Known Bugs or "Issues"

Most of the trouble we have with this implementation of Zfone stems from the complexity of detecting the VoIP client's SIP and RTP packets on the fly, figuring out what UDP port numbers they use, and triggering ZRTP protocol whenever these packets are detected. That whole class of problems would disappear if the ZRTP protocol were integrated inside a VoIP client. The packet detection problems only arise because we implement the ZRTP protocol in this particular product outside the VoIP client as a "bump in the cord".

Here are the known issues in this version of Zfone:

Some VoIP clients attempt to traverse NAT routers by sending RTP voice and video packets through TCP instead of UDP. This protocol tunneling violates the IETF standards for VoIP, which require that RTP media packets be sent over UDP. Zfone assumes that RTP will be found only in UDP packets, and thus will not detect RTP sent through TCP. In that case, Zfone's GUI displays the "Idle" status during a call, and does not engage the ZRTP protocol. Sometimes the packets are going through a media relay which converts them to UDP for the other party, whose Zfone client can therefore see the media stream, but searches in vain for the idled ZRTP peer and displays the "NOT Secure / No ZRTP Peer" status.

If this happens, here are a couple of workarounds: 1) The best solution is to move one of the parties' computers (in particular, the one that displays IDLE) off their local network to an external IP address, thereby simplifying the NAT traversal problem. Even better, move both computers to external IP addresses. 2) Or it might help to switch one of the parties (especially the IDLE one) to a different VoIP client. Often the VoIP client software decides to straighten up and follow the standards when talking to a VoIP client from another vendor.

Any form of protocol tunneling will subvert Zfone's RTP detection mechanism. In fact, most protocol tunneling is done to defeat various packet filtering mechanisms, such as firewalls. This does not indicate a problem with the ZRTP protocol. It's related to trying to run the ZRTP protocol as a packet filter in the IP stack, as Zfone does. It's a problem that would go away completely if the ZRTP protocol were integrated inside a VoIP client, for example by using our Zfone SDK. We are working on improvements in Zfone's SIP/RTP detection logic.
Mac OS X users may have trouble with the new Leopard version of iChat in some cases. Sometimes iChat loses the connection. We are working on a fix.
Max OS X users may find that Zfone interferes with their ability to turn their OS X built-in firewall on or off. To see an example of this, go into the System Preferences and run the Sharing Preferences, and click on the Firewall settings. OS X won't let you modify your firewall settings as long as Zfone is running, because OS X thinks Zfone is another firewall product. If you need to do anything to your firewall settings, you should be able to do it by using the Zfone menus to turn off the Zfone packet filter. Then you are free to modify your firewall settings. After that, you can tell Zfone to start packet filtering again.