Aastra Telecom 41-001343-02 Encrypted Files on the IP Phone, Configuration File Encryption Method

Encrypted Files on the IP Phone

Encrypted Files on the IP Phone

An encryption feature for the IP phone allows Service Providers the capability of storing encrypted files on their server to protect against unauthorized access and tampering of sensitive information (i.e., user accounts, login passwords, registra- tion information). Service Providers also have the capability of locking a phone to use a specific server-provided configura- tion only.

Configuration File Encryption Method

Only a System Administrator can encrypt the configurations files for an IP Phone. System Administrators use a password distribution scheme to manually pre-configure or automatically configure the phones to use the encrypted configuration with a unique key.

From a Microsoft Windows command line, the System Administrator uses an Aastra-supplied configuration file encryption tool called "anacrypt.exe" to encrypt the <mac>.tuz file.

Note:

Aastra also supplies encryption tools to support Linux platforms (anacrypt.linux) if required.

This tool processes the plain text <mac>.cfg, <model>.cfg, and aastra.cfg files and creates triple-DES encrypted versions called <mac>.tuz, <model>.tuz, and aastra.tuz. Encryption is performed using a secret password that is chosen by the administrator.

The encryption tool is also used to create an additional encrypted tag file called security.tuz, which controls the decryption process on the IP phones. If security.tuz is present on the TFTP/FTP/HTTP server, the IP phones download it and use it locally to decrypt the configuration information from the aastra.tuz and <mac>.tuz files. Because only the encrypted ver- sions of the configuration files need to be stored on the server, no plain-text configuration or passwords are sent across the network, thereby ensuring security of the configuration data.

To make changes to the configuration files, the System Administrator must save the original files.

Note:

If the use of encrypted configuration files is enabled (via security.tuz or pre-provisioned on the IP phone) the aastra.cfg, <model>.cfg, and <mac>.cfg files are ignored, and only the encrypted equivalent files aastra.tuz, <model>.tuz, and <mac>.tuz are read.

The security feature described above prevents unauthorized parties from reading or writing the contents of the <MAC>.tuz file. It also provides the following:

•Prevents users from using the <MAC>.tuz file that does not match the user’s phone MAC address.

•Renders the <MAC>.tuz file invalid if the user renames the file.

•Works with IP phone releases prior to Release 2.2.

•Provides compatibility between the previous encryption routine and the new decryption routine.

41-001343-02 REV04 – 05.2014 7-2