Virtual Number

A virtual number, also known as direct inward dialing (DID) or access numbers, is a telephone number without a directly associated telephone line. Usually, these numbers are programmed to forward incoming calls to one of the pre-set telephone numbers, chosen by the client: fixed, mobile or VoIP. Virtual Mobile Numbers (VMNs) are numbers used with mobiles and capable of receiving SMS.

See Melrose Labs Voice Gateway/Inbound Voice,
  Melrose Labs Tyr SMS Gateway/Virtual Mobile Numbers

Melrose Labs: 我们的使命是为企业,短信聚合器和消息传递提供商提供跨移动,固定电话和互联网的云通信中的关键服务。这些服务使组织能够在向客户提供服务,可靠性,对服务的洞察力以及提高的运营效率方面取得飞跃。