User`s guide

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Allow the PPP interface to answer incoming calls
When checked, this checkbox will cause the PPP instance to answer an incoming call.
Only allow calling numbers ending with n
When set to answer calls, the value in this textbox provides a filter for ISDN sub-
addresses. This value is blank by default but when the PPP instance is set to answer calls,
only numbers having trailing digits that match the sub-address value in this test will be
answered. So for example, if this value is set to “123”, only calls from numbers with
trailing digits that match this value will be answered. For example 01942 605123
Close the PPP connection after s seconds
The value in this textbox specifies the maximum time that the link will remain active in any
one session. After this time, the link will be deactivated.
if it has been up for m minutes in a day
The router will deactivate the PPP instance after it has been active for the value specified
in this text box.
if it has been idle for h hrs m mins s secs
The router will deactivate the PPP instance after the time specified in these text boxes if
it detects that the link has not seen traffic.
Alternative idle timer for static routes s seconds
The value in this text box specifies an alternative inactivity timeout for use in conjunction
with the “Make PPP n interface use the alternative idle timeout when this route becomes
available” parameter on the Configuration – Network > IP Routing/Forwarding >
Static Routes > Routes n > Advanced web page. This timeout will only be used until
the PPP instance next deactivates. After that the normal timeout value is used.
If the link has not received any packets for s seconds
The value in this text box specifies the amount of time that the router will wait without
receiving any PPP packets before disconnecting. The timer is reset with each received PPP
packet.
if the negotiation is not complete in s seconds
The value in this textbox specifies the maximum time (in seconds) allowed for the PPP
negotiation to complete. If negotiations have not completed within this period, the
interface is deactivated.
Enable NAT on this interface
When checked, this checkbox causes the router to apply Network Address Translation (NAT)
to IP packets on this interface. When enabled, the following additional parameters appear:
IP address/IP address and Port
These radio buttons select whether IP address translation only should be applied or
whether port number translation should also be applied to IP packets.
NAT Source IP address a.b.c.d
This text box contains the IP address of the interface that should be used as the source
address in IP packets crossing the NAT interface.
Enable IPsec on this interface
When checked, this checkbox causes the router to use the IPsec protocol to secure the
connection. When enabled, the following additional parameters appear:
Keep Security Associations (SAs) when this PSTN interface is disconnected
When checked, this checkbox causes the router to maintain (i.e. not flush) the SA when
the interface becomes disconnected. The normal behaviour is to remove the SAs when
the interface becomes disconnected.