User`s guide

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Sub-address
The value in this text box specifies the ISDN sub-address filter to use in conjunction with
the ISDN answering function. When answering is set to On and there is a valid sub-address
in this text box, the router will only answer calls where the trailing digits of the calling sub-
address match this sub-address. For example, setting the sub-address value to 123 will
prevent the router from answering calls where the sub-address does not end in 123.
Related CLI Commands
Entity
Instance
Parameter
Values
Equivalent Web Parameter
l2tp n retxto
0 - 4294967296
Retransmit interval s
milliseconds
l2tp n retxcnt
0 - 4294967296
Retransmit count
l2tp n l1iface 0 – 255 Layer 1 Interface
l2tp n ans OFF,ON
Allow this L2TP tunnel to answer
incoming ISDN calls
l2tp n msn Up to 9 digits MSN
l2tp n sub Up to 17 digits Sub-address
PPTP
Configuration - Network > Virtual Private Networking (VPN) > PPTP
The Point-to-Point tunnelling protocol (PPTP) is a common way of creating a VPN tunnel to a
Microsoft Windows™ server.
PPTP works by ending a regular PPP session to the peer encapsulated by the Generic
Routing Encapsulation (GRE) protocol. A second session on TCP port 1723 is used to initiate
and manage the GRE session. PPTP connections are authenticated with Microsoft MSCHAP-
v2 or EAP-TLS. VPN traffic is protected by MPPE encryption. PPTP does not work with
GPRS/HSDPA mobile operators that assign a private IP address and then apply NAT to the
traffic before it leaves their network. This because the server tries to build a tunnel back to
the router on port 1723 but fails when the traffic is blocked by the mobile operators’
firewall.
PPTP n
Configuration - Network > Virtual Private Networking (VPN) > PPTP > PPTP n
Description
The text string in this text box is a name to aid the identification of the router.
Remote Host a.b.c.d
The value in this text box specifies the IP address of the remote host, i.e. the device that
will terminate the PPTP connection.
Use Interface x,y
The interface to be used for the PPTP tunnel is selected from this drop-down list, the text
box next to it is for the interface instance. Specifying these parameters allow the router to
raise the interface should it be disconnected. The interface options are:
• Auto
• PPP
• Ethernet.