Draytek Vigor2820 Series User Manual page 214

IP Address Assignment
Method (IPCP)
Select Dialing to Dual ISPs if you have more than one ISP. You will be able to dial to both
ISPs at the same time. This is mainly for those ISPs that do not support Multiple-Link PPP
(ML-PPP). In such cases, dialing to two ISPs can increase the bandwidth utilization of the
ISDN channels to 128kbps data speed.
Common Settings
PPP/MP Setup
Vigor2820 Series User's Guide
will always remain on.
In most environments, you should not change these settings as
most ISPs provide a dynamic IP address for the router when it
connects to the ISP. If your ISP provides a fixed IP address, check
Yes and enter the IP address in the field of Fixed IP Address.
Enable Dual ISPs Function - Check to enable the Dual ISPs
function. Require ISP Callback (CBCP) -If your ISP supports
the callback function, check this box to activate the Callback
Control Protocol during the PPP negotiation.
There are three link types provided here for
Link Type
–
different purpose.
Link Disable disables the ISDN dial-out
function. Dialup 128Kbps allows you to use both ISDN B
channels for Internet access. Dialup BOD (for detailed
information of configuration, please refer to section 3.12.4) stands
for bandwidth-on-demand. The router will use only one B channel
in low traffic situations. Once the single B channel bandwidth is
fully used, the other B channel will be activated automatically
through the dialup.
PPP Authentication - PAP only allows you to configure the PPP
session to use the PAP protocol to negotiate the username and
password with the ISP. PAP or CHAP can configure the PPP
session to use the PAP or CHAP protocols to negotiate the
username and password with the ISP.
Idle Timeout - Idle timeout means the router will be disconnect
after being idle for a preset amount of time. The default is 180
seconds. If you set the time to 0, the ISDN connection to the ISP
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