[software] cdb, short for `constant database`, refers to both a library and data format created by Daniel J. Bernstein. cdb acts as an on-disk associative array, mapping keys to values, and allows multiple values to be stored for a single key. A constant database allows for only two operations: creation and reading. Both operations are desi... Found on http://en.wikipedia.org/wiki/Cdb_(software)
Call drop back. A number portability routing technique (as in MNP). CDB is an enhancement of OR (Onward Routing). When the donor network receives the call, it releases the call and returns a message indicating that the number has been ported (and providing routing information). This drop back message is used by a transit network or an originating network to route the call onward to the new destination.
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