Configuring Connection Settings

Procedure

1. Go to Administration → IMSVA Configuration → SMTP Routing.
2. Click the Connections tab.
   The Connections screen appears.
3. Specify the SMTP Interface settings.
   • Port: Specify the listening port of the SMTP server.
   • Disconnect after { } minutes of inactivity: Specify a time-out value.
   • Simultaneous connections: Click No limit or Allow up to { } connections and specify the maximum number of connections.
4. Specify the Connection Control settings.
   1. Select Accept all, except the following list to configure the "deny list" or Deny all, except the following list to configure the "permit list”.

      Note The "permit list" or "deny list" configured here overrides the Approved List or Block List configured for SMTP Traffic Throttling.

   2. Configure the list.
      • Single computer: Specify an IP address and then click >> to add it to the list.
      • Group of computers:
        1. Select the IP version.
           • For IPv4 addresses, specify a subnet address and mask.
           • For IPv6 addresses, specify a subnet address.
        2. Click >> to add the group to the list.
      • Import from file: Click to import an IP list from a file. The following shows sample content of an IP list text file:
        192.168.1.1
        192.168.2.0:255.255.255.0
        192.168.3.1:255.255.255.128
        192.168.4.100
        192.168.5.32:255.255.255.192
        2001:db8:10ff::ae:44f2
        2001:db8::/32
5. Specify the Transport Layer Security settings.
   1. Select Enable Incoming Transport Layer Security.
      This option enables the IMSVA SMTP Server to accept messages only through a TLS connection.
   2. Select Only accept SMTP connection by TLS for IMSVA to accept only secure incoming connections.
      This option enables the IMSVA SMTP Server to accept messages only through a TLS connection.
   3. Click a Browse button next to one of the following:
      • CA certificate: A CA certificate is usually used for verifying SMTP clients. However, IMSVA does not verify the client and only uses the CA certificate for enabling the TLS connection.
        Only upload this file if it is provided to you together with the public key. Otherwise, this file is not mandatory for enabling a TLS connection.
      • Private key: The SMTP client encrypts a random number using IMSVA SMTP server's public key and an encryption key to generate the session keys.
        IMSVA SMTP server then uses the private key to decrypt the random number in order to establish the secure connection. This key must be uploaded to enable a TLS connection.
      • SMTP server certification: The IMSVA SMTP server's public key made available to the SMTP clients for generating the session keys.
        This key must be uploaded to enable a TLS connection.
   4. Click Upload to save the file to the IMSVA server.
   5. Select Enable Outgoing Transport Layer Security to protect outbound messages, if desired.
6. Click Save.