CLI stands for Caller ID. Caller ID is a significant feature in VoIP. Caller ID is when calling to another phone, your number will appear in Caller ID so they can recognize it is you.
Typically when calling locally in your country, you do not need to be concerned about caller ID because it is something that is guaranteed. When calling internationally, you are not definite the CLI feature thus it is the responsibility of the wholesaler to check thoroughly. In VoIP wholesale termination, one can decide to allow CLI routes or to not let them. Generally for termination providers, CLI routes are more expensive than non CLI as a result they choose non CLI for the reason that customer always wants cheap rates with good quality.
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