When you use your mobile phone while traveling to a different country it is called roaming. And your home phone company charges you roaming fees. The issue is, these roaming fees are excessive. Each mobile phone company has roaming relationships around the world, these roaming relationships are in effect the same relationship an MVNO would have with its MNO host. So for example a Canadian customer of Rogers Wireless in Canada who travels to the USA will roam over to the AT&T network in the USA. AT&T is Rogers' roaming partner. Considering the size of Rogers and the volume of roaming, Rogers is likely to have one of the best wholesale agreements with AT&T. (Rogers is the largest Mobile Phone Company in Canada with approx. 9,376,000 subscribers. Since 65% of Canadians travel to the USA at least once a year, Rogers would be sending about 6 million roaming customers a year towards AT&T.) That means that Rogers

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