3.4
Existing types of operator cooperation
Different forms of cooperation between operators have existed for many years, na- tional and international roaming solutions are well known examples. When 3G systems were introduced in Europe after year 2000 cooperation between 3G op- erators was discussed and considered by most operators in Western Europe. In many countries sharing agreements were signed and operators started to deploy and operate shared networks.
This section will provide an overview of solutions where operators share the network resources in different ways. The focus is on cooperative aspects between actors with description of shared networks, national roaming and mobile virtual operators (MVNOs). First, a market example is presented.
An example - shared networks in Sweden
Sweden is an interesting example of a market with several network sharing agree- ments in operation. In December 2000 four 3G licenses were awarded. Two opera- tors had GSM services and networks, Tele2 and Europolitan (later Vodafone and Te- lenor). Two were entrants at the Swedish market, Orange and Hi3G(Hutchison)33.
The largest mobile network operator, Telia (incumbent still state controlled), did not get any license. Orange did not deploy any network. The 3G license was re- turned to the Swedish regulator PTS and the spectrum were later allocated to the other licensees.
Europolitan and the 3G Greenfield operator Hi3G formed a joint venture and started the network company 3G Infrastructure (3GIS). Network sharing was al- lowed under the condition that the operators provided own dedicated networks for at least 30% of the population. The results was that Hi3G and Europolitan did build both an own network and a shared network, see Figure 3.1.
Figure 3.1: UMTS and GSM networks of Hi3G, Telenor and the joint venture 3GIS
Figure 3.2: GSM networks of Telia and Tele2 and the UMTS network run by the joint venture SUNAB
The operators also agreed that users of Hi3G could roam into the 2G networks of Europolitan in areas were Hi3G did not provide any 3G coverage. This agreement was ended 2008.
As mentioned Telia did not obtain any 3G license but the two competitors Tele2 and Telia decided to build a common 3G network using the Tele2 license and spectrum. They formed another joint venture called Svenska UMTS Nät AB (SUNAB) for planning and building a 3G network. Both operators continued to run their own GSM networks in the 900 MHz and 1800 MHz bands, see Figure 3.2. In April 2009 Telenor and Tele2 announced an agreement to enter a joint venture in Sweden Net4Mobility for deployment of "4G" in the 2,6 GHz frequency bands using LTE technology. Telia had decided to build its own 4G network and not to expand the cooperation with Tele2 for the deployment of LTE. After LTE trails 2009 Telia launched the first commercial LTE network in Stockholm July 2010.
3.4. EXISTING TYPES OF OPERATOR COOPERATION 43
National roaming
National roaming can be compared with the case of international roaming. When a user is abroad the mobile phone can connect to networks in the country provided that the home network operator has agreements with thevisitednetwork operators and that the mobile phone is within coverage of the networks. The phone can detect the other networks and the network selection can be made manually or automatically based on priority lists provided by the home network operator, see 3GPP TS 22.011 [145].
In the users home country the other operator networks are also detected and visible in the user terminal However, in the home country access to other operator networks is not possible unless operators have agreements about national roaming. Each operator network in every country has a unique network code called PLMN code (Public Land Mobile Network). The PLMN code and the PLMN selection are key concepts for all types of roaming and are also applied for shared networks and for Mobile Virtual Network Operators (MVNOs) [145].
"National Roaming is a service whereby an UE of a given PLMN is able to obtain service from another PLMN of the same country, anywhere, or on a regional basis. The availability of National Roaming depends on the home PLMN of the requesting UE and the visited PLMN; it does not depend on subscription arrangements"
Each operator has a two-digit mobile network code (MNC) to be used with the Swedish country code (MCC=240) in order to identify the home network (HPLMN) of the company when users are in Sweden. As an example the Swedish operators Telia, Hi3G, Tele2 and Telenor have the PLMN codes 24001, 24002, 24007 and 24008 respectively34. The MNC shall also enable roaming with other national and
international mobile networks for the own end-users. The Home PLMN (HPLMN) is the PLMN the customer belongs to and the Visitor PLMN (VPLMN) is the PLMN the customer is roaming in.
National roaming is one way to implement network sharing, so calledgeograph- ical split, where the sharing partners deploy network in specific areas and allow roaming. This was proposed in both UK and Germany for the roll-out of 3G net- works. National roaming is often discussed as way to lower the barriers for markets entrants. After year 2000 EU presented directives for 2G operators to allow na- tional roaming for 3G entrants in areas where the market entrant could not provide 3G coverage. In the UK it was a debate between the regulator and the incumbent operators about national roaming. Finally, no directives were needed, O2 voluntar- ily signed an agreement with "3" in the UK. As mentioned earlier, Europolitan and Hi3G in Sweden signed a similar agreement about national roaming. The roam- ing can be described in terms of configuration of the business roles of the involved operators, see Figure 3.4. A traditional mobile operator takes care of all types of business roles when the own customers are served. In the case of roaming the oper- ator of the visited network provide network resources. In order to allow the visiting
Figure 3.4: Activity groups and business roles for Mobile Network Operators, active business roles are colored. To the left - the red operator serves the own users; to the right - national roaming where the blue operator serves one red roaming user
user access to the network mechanisms for authentication and authorization are needed. In addition charging records needs to be collected and sent to the home network operator.
Mobile Virtual Network Operators
A Mobile Virtual Network Operator (MVNO) does not have any own access network and cooperates with a mobile operator that provides this resource, see Figure 3.5. If you compare Figures 3.4 and 3.5 the MVNO operation can be seen as a type of one-way constant national roaming. There are many types of MVNO´s where differences can be found in both the technical and business domains. MVNO´s have resources for marketing and sales, customer management and charging and billing. Some MVNOs also have own core network elements, important is to have networke nodes controlling the subscriber information.
The differences can be described by some examples from the Swedish market. Ventelo is a MVNO that uses the network of operator Hi3G. Ventelo is a separate company and has an own PLMN code, i.e. customers of Ventelo get SIM cards with this PLMN. Djuice is a subsidy of Telenor Sweden and uses the Telenor networks. Djuice has an own PLMN code. Halebop is a Telia brand. It uses the Telia network but has no own PLMN code.
3.4. EXISTING TYPES OF OPERATOR COOPERATION 45
Figure 3.5: Active Business roles for a Mobile Virtual Network Operator and a Mobile Network operator that provide the network resources to the MVNO
Network sharing
Networks can be shared in many different ways, both technically and business wise. Different solutions exist for how the core network nodes are connected to the radio access network control. Using a Gateway Core Network (GWCN) configuration the mobile network operators share the core network nodes MSC/SGSN. With a Multi-Operator Core Network (MOCN) configuration the core network nodes are operated by different operators but connected to the same RNC in the radio access network [99].
The shared networks in Sweden also have their own PLMN codes. There are a number of issues related to network selection and handover in scenarios where there is a mix of shared and non-shared networks. E.g. a moving user that has been served by a shared network needs to be handed over to the correct network. 3GPP has described cell selection and re-selection for these cases [101].
The configuration of business roles for the involved actors in the Swedish shared 3G networks are illustrated in Figures 3.6 and 3.7. Telenor and Hi3G both operate their own 3G networks and use the shared network provided by 3GIS. Hence, there are three separate networks. Telenor, Hi3G and 3GIS also have their own network planning groups. 3GIS has no own end-users, these are the customers of Telenor and Hi3G .
The cooperation between Telia and Tele2 is somewhat different to the case of Telenor and Hi3G . There is only one 3G license, the one awarded to Tele2, and one 3G network. Tele2 and Telia are both owners and customers of SUNAB, but
Figure 3.6: Business roles for the 3G networks provided by Hi3G and Telenor
they are also suppliers. SUNAB has no own network planning group, SUNAB uses the resources of Tele2 and Telia. In each of four geographical areas one operator is responsible for the network planning and deployment. Each operator also has it own Network operation center (NOC) for monitoring and control of the network35.
Figure 3.7: Business roles for 3G networks provided by Tele2 and Telia