AT&T MERLIN LEGEND Release 3.1 System Planning Manual page 184

System Features
5. Under the Preferred Trunk Pools heading:
a. Determine which of the toll trunk pools is used for calls to the greatest
number of different area codes. Write the number of that trunk pool in
the space next to For toll calls (Table 17).
b. Determine which of the local trunk pools is used for calls to the
greatest number of different exchanges. Write the number of that
trunk pool in the space next to For local calls (Table 18).
NOTE:
Tables 17 and 18 are explained later.
Figure 4–1 shows the completed Automatic Route Selection Worksheet for the
fictitious company, McHale and Associates of Denver, Colorado (area code:
303). McHale has a local trunk pool, an in-state WATS pool, and a cross-country
WATS pool. Because Colorado has two area codes (303 and 719), the in-state
WATS line/trunk can be used for both toll and local calls. Therefore, there are
two entries for Pool 890 on the worksheet.
The cross-country WATS trunk pool serves the greatest number of different area
codes, every area code in the country except the two in Colorado. Therefore, it
is the preferred trunk pool for toll calls.
The in-state WATS trunk pool serves the greatest number of different
exchanges. It is the preferred trunk pool for calls to every exchange in area
code 303, except the 20 exchanges in the local calling area. Therefore, it is the
preferred trunk pool for local calls and some of these are toll calls.
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Features