Billion BIPAC 8500 User Manual page 74

Billion BIPAC-8500 / 8520 SHDSL VPN Firewall Bridge / Router
Key Length: The data can be encrypted by MPPE algorithm with 40 bits or 128 bits.
Default is Auto, it is negotiated when establishing a connection. 128 bit keys provide
stronger encryption than 40 bit keys.
Mode: You may select Stateful or Stateless mode. The key will be changed every 256
packets when you select Stateful mode. If you select Stateless mode, the key will be
changed in each packet.
Idle Time: Auto-disconnect the VPN connection when there is no activity on the
connection for a predetermined period of time. 0 means this connection is always on.
Click Apply after changing settings.
Chapter 4: Configuration
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