AT&T 7100 series, 7500 series, 2500 series, 7200 series, 7400 series manual Call Routing ETN to SDN

ELECTRONIC TANDEM NETWORK (ETN) THROUGH THE ETN AND PNA PACKAGES				5-11
_______________________________________________________________________________________
_
AT&T SDN
NCP	(3)
	DATA BASE
	QUERY
ETN		(4)
PNI		BILLING &
		ROUTING
ACP	ACP	INSTRUCTIONS
SO
(5)
ROUTE		(2)
CALL		592-3456
(6)
592-3456
3456		SO	SDN
			DIRECT
592			ACCESS
			(1)
			8-592-3456

Figure 5-6.Call Flow SDN - to - ETN

4.The ACP updates any pertinent billing records.

5.Based upon the information it received from the NCP, the ACP routes the call to the egress ACP (a 4ESS). Before routing the call, the egress ACP may alter the called number to conform to the ETN dial plan.

6.The destination ETN receives the call, and routes it to the switch indicated by the RNX. The destination switch rings the terminal indicated by the extension number it receives.

Call Routing — ETN to SDN

To route ETN calls to non-ETN locations through SDN, the following steps occur (see figure 5-7):

1.At a main switch, the caller dials the 7-digit (RNX-XXXX) or 10-digit (NPA-NXX-XXXX) number of the destination terminal.

2.The main passes the destination terminal number to the ETN tandem for routing.

3.The tandem passes the 7- or 10-digit destination terminal number onto the AT&T serving office, which forwards the call onto the nearest ACP.

4.The ACP queries the NCP database, which returns the routing number.

5.The ACP updates any pertinent billing records.

6.Based upon the information it received from the NCP, the ACP changes the destination terminal number (if necessary) and routes the call to the egress ACP.