In accordance with an improved call routing methodology, a call is routed
within a communication network by reference to one or more databases. In
response to receiving a local number portability request at a service
control point (SCP), the SCP accesses one or more databases to determine
whether or not to apply custom call routing to a call directed to a
called telecommunications number. In response to determining to apply
custom call routing to the call, the SCP performs at least a second
access to the one or more databases to obtain a local routing number
(LRN) associated within the one or more databases with a calling
telecommunications number associated with the call. The SCP thereafter
provides the LRN to a service switch point in the communication network
so that the call is routed to a called station associated with the called
telecommunications number.