HP MSR Router Series Wan Access Configuration Manual page 181

Traditional DDR
You can configure traditional DDR by using the following methods:
• Configure DDR parameters directly on a physical interface.
The router places or receives calls through the physical interface.
The physical interface can correspond to one or more call destinations.
This method applies when only one interface places or receives calls.
Configure DDR parameters on a dialer interface.
•
A dialer interface is associated with a group of physical interfaces and controls which physical
interface to use to place or receive calls.
A dialer interface can correspond to one or more call destination addresses. In the case of
multiple call destination addresses, the dialer interface can use any associated physical
interface to place calls to any of the call destination addresses.
A physical interface can belong to only one dialer interface.
This method applies when one or more interfaces place or receive calls.
Bundle DDR
When using bundle DDR, you can configure DDR parameters on a dialer interface, but not directly on a
physical interface.
A dialer interface corresponds to a dialer bundle. A dialer bundle can contain multiple physical
interfaces with different priorities. Each time a call is placed, the highest-priority physical interface
available is selected. If one of physical interfaces with the same priority is selected, these interfaces are
selected in a round-robin manner when they are the highest-priority physical interfaces available.
A dialer interface can have only one call destination.
A physical interface can belong to multiple dialer bundles and can be used by multiple dialer interfaces
at different times.
Comparison of traditional DDR and bundle DDR
Traditional DDR is widely used, but its limitations result in poor extensibility. Traditional DDR is based on
one-to-one bindings between dial services and physical interfaces. A new dial service requires a new
physical interface.
NOTE:
A dial rule (configured by using the dialer-group rule command) defines one dial service.
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