User's Manual

Configuring Call Routing
Understanding the call-routing database
APX 8000/MAX TNT/DSLTNT Physical Interface Configuration Guide Preliminary May 9, 2000 19-3
How call routes affect device usage
The system sorts its call-routing database entries after a reset. During active use, the system
applies operational criteria, such as availability and frequency of use, to the order in which it
uses devices.
By default, entries for modem devices are sorted to load-balance calls across the modem cards
in a quadrant, and entries for HDLC channels are sorted to group the channels of a multilink
call on a single card when possible. For both types of calls, cards in lower-numbered slots
precede those in higher-numbered slots.
Entries for trunk lines are initially sorted in the order in which the lines are installed in the
system, with lines in lower-numbered slots preceding those in higher-numbered slots.
Modem usage and database sort order
The default sort order for modems is determined by the following parameter, shown with its
default settings:
[in SYSTEM]
call-routing-sort-method = item-first
In a device address, the item number represents a particular device on a slot card. An item
number of 0 (zero) denotes the whole slot, and the numbering begins with the leftmost device
on the card. The Item-First sort method means the system sorts the components of device
addresses in the following order:
item:shelf:slot:logical:item
For example, if two modem cards are supported, one in shelf 1, slot 2 and the other in shelf 1,
slot 4, the initial modem usage order looks like this:
1:1:2
1:1:4
2:1:2
2:1:4
3:1:2
Source The address of a device that receives calls The address has the
same format as the Device field.
Type The call-routing type. For default entries (entries created by the
system) the value depends on the type of installed device. For
entries created by user-specified Call-Route profiles, see
“Call-Route profile settings” on page 19-5.
TG A trunk group number. The default is zero.
SA An ISDN subaddress number. The default is zero.
Phone A telephone number.
Table 19-1. Fields in a call-routing database entry (continued)
Field Contains