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Caller ID (caller identification or CID, and more properly calling number identification - CNID) is a telephony intelligent network service that transmits the caller's telephone number and in some places the caller's name to the called party's telephone equipment during the ringing signal or when the call is being set up but before the call is answered. In the USA, CNID is typically transmitted digitally using Bell 202 modulation between the first and second rings, but in other countries other methods are also used. Instead of sending the caller ID in between the first and second ring, some systems use a "line reversal" to announce the caller ID, or caller ID signals are simply sent without any announcement. Instead of Bell 202 the European alternative V.23 is sometimes used, (without the 75 baud reverse channel) or the data is sent using DTMF signalling.