NB-IoT refers to a standard see Vodafone white paper...

NB-IoT refers to a standard

see Vodafone white paper
http://www.vodafone.com/business/io...ords_iot_gated_&src=marcom_adwords_iot_gated_

or in summary
https://www.iotforall.com/what-is-narrowband-iot-nb-iot/

Narrowband IoT (also known as NB-IoT or LTE-M2) is a proposed LPWAN technology which won’t operate in the LTE construct. Instead, it’s being designed to exist in one of three ways:

• Independently
• In unused 200-KhZ bands that have previously been used for GSM (Global System for Mobile Communications)
• On LTE base stations allocating a resource block to NB-IoT operations or in their guard bands.

Telecommunication giants such as Huawei, Ericsson, Qualcomm, and Vodafone are actively involved in putting this standard together. In fact, Vodafone is set to roll out the first live, commercial NB-IoT launch markets in early 2017 in Germany, Ireland, the Netherlands and Spain.