Digi TransPort LR54 - Configure Ciphers and Digests for Use on the Openvpn Tunnel

Virtual Private Networks (VPN) OpenVPN
Digi TransPort WR Routers User Guide
212
Command line
n Configure the username and password. For example, to configure the username ny-office and
password abcdefgh, the commands are:
digi.router> openvpn-client 1 username ny_office
digi.router> openvpn-client 1 password abcdefgh
Configure ciphers and digests for use on the OpenVPN tunnel
By default, the OpenVPN server negotiates with the OpenVPN client the cipher that will be used to
encrypt data being sent over the OpenVPN tunnel. The ciphers that will be used for the negotiation
can be configured as a list. In order for the negotiation to be successful, the OpenVPN client's cipher
list must include the first cipher in the OpenVPN server's cipher list. OpenVPN clients that do not
support cipher negotiation can use any cipher in the OpenVPN server's cipher list to connect.
To force the OpenVPN client or server to use a specific cipher, then only the desired cipher should be
configured in the list.
By default, the OpenVPN client and server support the following ciphers for negotiation:
n AES 128 CBC
n AES 192 CBC
n AES 256 CBC
n AES 128 GCM
n AES 192 GCM
n AES 256 GCM
When using CBC encryption algorithms, the OpenVPN client and server will also use a digest to
authenticate the data sent over the OpenVPN tunnel. The digest configured on the OpenVPN client
must match the digest configured on the OpenVPN server.
By default, the OpenVPN client and server will use SHA1 for authentication.
The digest is not used when a GCM encryption algorithm is in use, since GCM encryption includes built-
in digest functionality.
Web
For OpenVPN Server
1. On the menu, click Network > Networks > OpenVPN and select OpenVPN Server. The
OpenVPN Server page appears.
2. Click Edit. The OpenVPN server page displays the settings for the OpenVPN Server.
3. Enter the Encryption settings:
n Cipher: Select the desired ciphers that the OpenVPN can use for an OpenVPN tunnel.
Note The order of the ciphers is important for cipher negotiation. The first cipher in the
list will be used if both the OpenVPN client and server support cipher negotiation.
4. Click Apply.