Roaming is a concept in telecom by which services bought in a specific country with a specific operator can be used in a “different country” with a different operator.
As a basic concept every mobile operator in the world has (or ideally should have) a roaming partnership with all other operators, so its user can go to any part of the world and “seamlessly” utilise the service. However, it is a bit more complicated than that and operators use different arrangements to deliver the roaming propositions.
Below are some arrangements that operator enter into to provide roaming services.
The two types of roaming are discussed below.
- National Roaming: In such arrangements, an operator A in a country can use the radio network of operator B in the same country. E.g., Say an AT&T customer can use the radio network infrastructure of say T-Mobile where AT&T does not have radio presence.
- International Roaming: International roaming occurs when the visited network is in a different country than the home network. E.g., a Vodafone UK customer goes to Argentina and uses Claro’s network.
Essentially, the international roaming agreements are negotiated in two ways.
- Direct Roaming: In direct roaming, the MNO or an MVNO has to sign individual roaming agreements with one (or all) operators in every country.
- Unilateral roaming: This type of roaming is usually signed by an MVNO in the home country with an MNO in the visited country. This will allow the users of the MVNO network (in home country) to use the infrastructure of the visited network. Primary reason for such an agreement is that the MVNO does not have its own radio assets to share with the other operator hence a unilateral arrangement is used.
- Bilateral Roaming: This is not for MVNO and is generally signed between two MNO’s. This allows the users of each MNO to share their infrastructure for the visitors from the other network. This is a two-way agreement and it is the most common type.
- Sponsored Roaming: As you would appreciate that signing, “Direct roaming” agreements with every country in the world might by a long and expensive process. To counter that, an MNO (or an MVNO) can buy roaming services through a large MNO. The seller MNO now becomes a provider (or a single point) for all roaming services that will be used by customer MNO (or MVNO). However, in this arrangement, the Sponsored Roaming provider acts as broker to provide roaming rates to the buyer operator. Generally, in such arrangements the buyer operator ends up getting great (lower) rates to some destinations and bad (expensive) rates for others. A sponsored roaming market could be seen as secondary trading platforms for roaming rates.
Flow if Money:
The exhibit demonstrates the flow of money in a typical roaming scenario.
- A typical user pays for roaming services to its operator.
- The operator pays the visited network to buy roaming services for its users. The rates and terms of this are part of the roaming agreement.
- The visited network has to buy transit services for traffic from third party providers.
- The third-party providers have to pay the home network to terminate traffic.