Cisco Systems ATA 186 Telephone User Manual


 
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Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide for MGCP (version 3.0)
OL-4803-01
Chapter 3 Configuring the Cisco ATA for MGCP
Configuring the Cisco ATA Using a TFTP Server
Syntax examples
The cfgfmt.exe syntax affects how the EncryptKeyEx or EncryptKey parameters are used, as shown in
the following examples. In these examples, input-text-file is the ata<macaddress>.txt file that you will
convert to binary to create the ata<macaddress> configuration file(s) for the Cisco ATA;
output-binary-file is that binary ata<macaddress> file, and Secret is the encryption key.
cfgfmt -mgcp -tptag.dat input-text-file output-binary-file
If input-text-file sets the Cisco ATA EncryptKey parameter to 0, then output-binary-file is not
encrypted. If the input-text-file sets EncryptKey to a non-zero value, then output-binary-file is
encrypted with that value.
cfgfmt -X -mgcp -tptag.dat input-text-file output-binary-file
This is an example of how you might perform encryption on a first-time Cisco ATA.
The -X (uppercase) option means that any value specified for the Cisco ATA EncryptKeyEx
parameter in input-text-file is ignored. However, because Secret is not specified in this example,
output-binary-file is not encrypted. Nevertheless, the EncryptKeyEx parameter and its value, if
specified in input-file-text, will be included in output-binary-file for possible encryption at a later
time. The next time the Cisco ATA fetches the configuration file from the TFTP server, the file will
be encrypted with Secret.
cfgfmt -X -xSecret -mgcp -tptag.dat input-text-file
output-binary-file
This is an example of changing the encryption key from one key to another key.
The -X (uppercase) option means that any value specified for the Cisco ATA EncryptKeyEx
parameter in input-text-file is ignored and the output-binary-file is encrypted with the Secret key.
However, the EncryptKeyEx parameter and its value, if specified in input-text-file, will be included
in output-binary-file.
Examples of Upgrading to Stronger Encryption Key
This section contains two examples of how you would upgrade your Cisco ATA configuration to use the
stronger encyrption method if the current Cisco ATA firmware version was a version earlier than version
2.16.2. Versions earlier than 2.16.2 do not support the stronger EncryptKeyEx parameter.
Example 1
In this example, the Cisco ATA has not yet been deployed, but its firmware version is earlier than 2.16.2.
Therefore, the Cisco ATA will upgrade to to firmware version 3.0 to use the EncryptKeyEx parameter as
its encryption key.
The Cisco ATA in this example has a MAC address of 102030405060.
Perform the following steps:
Procedure
Step 1 Create a file called ata102030405060.txt by using the applicable example.txt file provided with the
Cisco ATA software. (For example, for MGCP, the example.txt file is called mgcp_example.txt.)
Step 2 Modify the ata102030405060.txt file with desired parameter values. The value of the EncryptKey
parameter should be 0.