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42Chapter 4 CS 1000 considerations
cEnsure that the DN Type is Public (Unknown).
dIn the External Number field, enter the
eAssign the PSTN line pool to the route (select the line pool from the Use Pool list; default is A).
4Add a destination code.
a Access the Dialing Plan - Routing panel (Configuration > Telephony > Dialing Plan > Routing) and select the Destination Codes tab.
b Add a new destination code.
Use the ALTPrefix as the destination code.
cOn the ALTPrefix Destination Code row, select the Normal Route field.
dEnter the route for the route added above (996).
eIn the adjacent Absorbed Length field, select 3 from the list.
When the SRG receives the ALTPrefix+DN digits from the main office, it looks up the destination code table, finds a match for the ALTPrefix, dumps the 3- digit ALTPrefix, appends the DN to the External Number and dials the External Number+DN.
Emergency Services Access (ESA) configuration
The Main Office Configuration for Survivable Remote Gateway 50
There are two methods of ESA support:
•When a user dials 911, the telephone is redirected to the Branch Office and connects to the SRG in local mode. The Main Office indicates the reason for redirection (as e911) in the DRAM. The SRG dials 911 across the PSTN. The telephone remains in local mode after the 911 call and is redirected to the Main Office after 10 minutes.
•
Note: This procedure applies only to redirected IP telephones when the
SRG is in normal mode.
For IP telephones in local mode, and for other telephones at the SRG, see the Networking Configuration Guide