Some telephones, depending on the brand and model, have the intercom function, which allows to begin communication by sending the signal. When the signal comes, the telephone set rings a signal different from the standard ring tone call. After that the telephone temporarily switches off from the telephone line and works as an intercom.
Netappel is a structure specialized in the field of VOIP COTE D IVOIRE. We sell call times from Internet. Our customers consists of enterprise and individuals
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