A Mobile Virtual Network Operator is a company that does not own a licensed frequency spectrum, but resells wireless services under their own brand name, using the network of another mobile phone operator.
An MVNO's roles and relationship to the mobile phone operator vary by market. In general an MVNO is an entity or company that works independently of the operator and can set its own tariff structures with its own infrastructure, such as Mobile Switching Center(MSC) or Home Location Register (HLR), but lacks a radio access network.
The first successful MVNO was Virgin Mobile, launched in the United Kingdom in 1999.
MVNOs are a way to implement a more specific marketing mix, whether alone or with partners and they can help attack specific, targeted segments.
MVNO models mean lower operational costs for mobile operators (billing, sales, customer service, marketing), help fight churn, grow average revenue per user by providing new applications and tariff plans and also can help with difficult issues like how to deal with fixed-mobile convergence by allowing MVNOs to try out more experimental projects and applications.
MVNOs are new breed of wireless network operators who may not own the wireless spectrum, or wireless infrastructure (also termed pipe, in colloquial terms) but give a virtual appearance of owning a wireless network.
MVNOs generally provide both voice and data services to end users through a paid up subscription agreement.
To become an MVNO, you should cobble together a partnership that consists of a connectivity partner (typically a traditional wireless network provider who owns the infrastructure and spectrum), cash, a customer base, and a sales channel.