Configure ISDN interfaces
Digi TransPort User Guide
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Use the following DNS servers if not negotiated
Primary DNS server
The IP address of the primary DNS server to use if a DNS server is not assigned as part of the
PPP negotiation and connection process. It is fairly common practice for the DNS server to be
assigned automatically by the ISP when making a connection.
Secondary DNS server
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 reveals 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 IP address of the primary DNS server that the remote peer should use when making DNS
requests over the link.
Secondary DNS server
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 causes the PPP instance to answer an incoming call.
Only allow calling numbers ending with n
When set to answer calls, the value in this setting 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
Enables Network Address Translation to operate on this interface. This is the same as for
other PPP interfaces.
IP address/IP address and Port
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 causes 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.
