AudioCodes Mediant 500L - Enabling SSH with RSA Public Key for CLI

User's Manual 90 Document #: LTRT-10532
Mediant 500L Gateway & E-SBC
 To enable Telnet:
1. Open the CLI Settings page (Setup menu > Administration tab > Web & CLI folder >
CLI Settings).
2. Configure the following parameters:
• 'Embedded Telnet Server': Select Enable Unsecured or Enable Secured (i.e,
SSL) to enable Telnet.
• 'Telnet Server TCP Port': Enter the port number of the embedded Telnet server.
• 'Telnet Server Idle Timeout': Enter the duration of inactivity in the Telnet session
after which the session automatically ends.
•
3. Click Apply, and then reset the device with a save-to-flash for your settings to take
effect.
For a detailed description of the Telnet parameters, see ''Telnet Parameters'' on page
1009.
7.2.2 Enabling SSH with RSA Public Key for CLI
Unless configured for TLS, Telnet is not secure as it requires passwords to be transmitted
in clear text. To overcome this, you can use Secure SHell (SSH) which is the de-facto
standard for secure CLI. SSH 2.0 is a protocol built above TCP providing methods for key
exchange, authentication, encryption, and authorization. SSH requires appropriate client
software for the management PC. Most Linux distributions have OpenSSH pre-installed;
Windows-based PCs require an SSH client software such as PuTTY, which can be
downloaded from http://www.chiark.greenend.org.uk/~sgtatham/putty/. By default, SSH
uses the same username and password as the device's Telnet and Web server. SSH
supports 1024/2048-bit RSA public keys, providing carrier-grade security.
Follow the instructions below to configure the device with an administrator RSA key as a
means of strong authentication.
 To enable SSH and configure RSA public keys for Windows (using PuTTY SSH
software):
1. Start the PuTTY Key Generator program, and then do the following:
a. Under the 'Parameters' group, do the following:
♦ Select the SSH-2 RSA option.
♦ In the 'Number of bits in a generated key' field, enter "1024" bits.
b. Under the 'Actions' group, click Generate and then follow the on-screen
instructions.
c. Under the 'Actions' group, click Save private key to save the new private key to a
file (*.ppk) on your PC.