Amer Networks E5Web GUI - Manual (Page 173)

address of the interface.
User authentication
If user authentication is required by the ISP, the username and password can be setup in cOS
Core for automatic sending to the PPPoE server.
Dial-on-demand
If dial-on-demand is enabled, the PPPoE connection will only be up when there is traffic on the
PPPoE interface. It is possible to configure how the security gateway should sense activity on the
interface, either on outgoing traffic, incoming traffic or both. Also configurable is the time to wait
with no activity before the tunnel is disconnected.
Unnumbered PPPoE
When cOS Core acts as a PPPoE client, support for unnumbered PPPoE is provided by default. The
additional option also exists to force unnumbered PPPoE to be used in PPPoE sessions.
Unnumbered PPPoE is typically used when ISPs want to allocate one or more preassigned IP
addresses to users. These IP addresses are then manually entered into client computers. The ISP
does not assign an IP address to the PPPoE client at the time it connects.
A further option with the unnumbered PPPoE feature in cOS Core is to allow the specification of
a single IP address which is used as the address of the PPPoE client interface. This address can
serve the following purposes:
• The IP address specified will be sent to the PPPoE server as the "preferred IP". If unnumbered
PPPoE is not forced, the server may choose to not accept the preferred IP and instead assign
another IP address to the PPPoE client.
When the option to force unnumbered PPPoE is selected, the client (that is to say cOS Core)
will not accept assignment of another IP address by the server.
• The IP address specified, or possibly the address assigned by the PPPoE server when
unnumbered PPPoE is not forced, will serve as the IP address of the PPPoE client interface.
This will be used as the local IP address for traffic leaving the interface when the traffic is
originated or NATed by the Clavister Security Gateway.
Note: PPPoE has a discovery protocol
To provide a point-to-point connection over Ethernet, each PPP session must learn the
Ethernet address of the remote peer, as well as establish a unique session identifier.
PPPoE includes a discovery protocol that provides this.
PPPoE cannot be used with HA
For reasons connected with the way IP addresses are shared in a cOS Core high availability
cluster, PPPoE will not operate correctly. It should therefore not be configured with HA.
Example 3.17. Configuring a PPPoE Client
Chapter 3: Fundamentals
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