User`s guide

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common practice for the DNS server to be assigned automatically by the ISP when
making a connection.
Secondary DNS server
The value in this text box specifies the IP address of the secondary DNS server to use if
one is not automatically assigned by the remote peer.
Attempt to assign the following IP configuration to remote devices
When checked, this check box will reveal the following four configuration parameters which
control how the PPP instance assigns an IP address to a connecting remote peer. The
primary and secondary DNS server addresses will also be sent to the remote peer
Assign remote IP addresses from a.b.c.d to a.b.c.d
The IP addresses in these text boxes define the pool of IP addresses to assign to remote
peers during the IP protocol configuration phase of the PPP negotiation process.
Primary DNS server
The value in this text box is the IP address of the primary DNS server that the remote
peer should use when making DNS requests over the link.
Secondary DNS server
The value in this text box is the IP address of the secondary DNS server that the remote
peer should use when making DNS requests, should the primary server be unavailable.
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
Enable NAT on this interface
When checked, this checkbox will enable Network Address Translation to operate on this
interface. This is the same as for other PPP interfaces.
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.
Enable IPsec on this interface
When checked, this checkbox will cause the router to encrypt traffic on this interface using
the IPsec protocol. The following two additional configuration parameters are revealed when
this box is checked.
Keep Security Associations (SAs) when this ISDN 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.
Use interface x,y for the source IP address of IPsec packets
If it is required to use another interface (i.e. not the interface currently being configured)
as the source address for IPsec packets, this may be achieved by selecting the desired
interface from the drop-down list and typing the desired interface instance number into
the adjacent text box.
Enable the firewall on this interface