ESN (electronic serial number)

admin — Tue, 13 Mar 2007 11:04:30 +0000

ESN (electronic serial number)

The unique identification number embedded in a wireless phone by the manufacturer. Each time a call is placed, the ESN is automatically transmitted to the base station so the wireless carrier's mobile switching office can check the call's validity. The ESN cannot easily be altered in the field. The ESN differs from the mobile identification number, which is the wireless carrier's identifier for a phone in the network. MINs and ESNs can be electronically checked to help prevent fraud. (Cingular)

Electronic Serial Number (ESN) is created by the FCC to uniquely identify mobile devices since AMPS days in the United States in mid-1980s. Later the administrative role was taken over by TIA in 1997. ESN is mainly used with AMPS and CDMA phones in the United States, compared with IMEI used for GSM phones in Europe and other places.

ESN is 32-bit long. In the old format, the first 8-bit is used to represent the manufacturer. Code 0x80 was reserved and now it is used to represent pseudo ESN (pESN). The last 24-bit are used as serial number with that manufacturer. » read more »