MORAN Multi-Operator RAN – What is it? Key differences

The Multi-Operator Radio Access Network (MORAN), also termed “Split in the eNodeB,” refers to a network architecture where a Radio Access Network (RAN) node, specifically an eNodeB, is shared among multiple operators. This sharing extends to splitting the RAN node’s resources amongst two or more network providers. In a MORAN setup, each operator maintains distinct core network components such as the Mobility Management Entity (MME), Serving Gateway (SGW), Packet Data Network Gateway (PDN GW), Home Subscriber Server (HSS), and others. It is important to recognize that regardless of the network configuration implemented, the Public Land Mobile Networks (PLMNs) associated with a cell are identified within the system information broadcasted by that cell. A cell is invariably associated with at least one PLMN, while a shared network cell is deemed part of all the PLMNs listed in its system information. With an increasing number of operators showing interest in RAN sharing—through measures such as possessing distinct frequencies or cells—the adoption of a comprehensive MORAN architecture is garnering attention. Nevertheless, challenges arise due to the Evolved-Universal Terrestrial Radio Access (E-UTRA) Radio Resource Control (RRC) protocol outlined in the 3GPP TS 36.331, which delineates the requisites for primary PLMN identity within the eNodeB. This can complicate the configuration of unique PLMN identities for different frequencies or cells, which is a prerequisite for achieving a MORAN configuration. Moreover, the need for discrete S1 connections for each frequency or cell with an MME, rather than a single connection at the eNodeB level, introduces additional complexity in establishing a MORAN network configuration.

In RAN sharing configurations where multiple cell identifiers are broadcast, the arrangement bears resemblance to MOCN due to each operator maintaining an independent 5G Core (5GC). Contrary to MOCN, which necessitates collaborative management of cell identifiers and Tracking Area Codes amongst operators, RAN sharing permits individual operators to autonomously establish their respective identifier allocation frameworks.

Usage of RAN sharing

5G mobile networks are poised to address the challenges arising from the surge in mobile broadband traffic, the growth in the number of mobile devices, and the evolution of user expectations. Specifically, mobile data traffic escalated by 69% in 2014, with projections indicating an almost eightfold increase from 2015 to 2020. The demand for high-speed connectivity—ubiquitous, always-on, and everywhere—is intensifying. Consequently, operators are tasked with network enhancements to broaden coverage, bolster capacity, support higher data rates, and improve end-to-end (E2E) latency, all while maintaining energy and cost efficiency.

Moreover, the rate of new technology adoption, network quality, and indoor coverage significantly influence customer choice and their willingness to pay for mobile access, positioning these factors as critical for Mobile Network Operators (MNOs) to balance profitability against costs. Network sharing emerges as a strategic solution to expedite coverage expansion, minimize deployment timeframes, and optimize resource use, while also enabling additional capital expenditure (CAPEX) and operational expenditure (OPEX) savings alongside the generation of new revenue streams.

Network sharing involves collaborative utilization of the Radio Access Network (RAN)—the infrastructure including the base station subsystem—among multiple MNOs. RAN is a substantial cost factor, accounting for approximately one-third of total OPEX and 80% of CAPEX, constituting 52% of total indirect network expenses. Such sharing arrangements yield significant benefits, spurring innovation as operators compete based on service offerings rather than infrastructure.

Especially for MNOs at the threshold of cost-saving potential or those seeking fresh investments, RAN sharing is beneficial. It is particularly advantageous in ‘greenfield’ scenarios, where new technologies may necessitate a comprehensive overhaul of network infrastructure. 5G networks are expected to increasingly incorporate RAN sharing to expedite the deployment of new RANs cost-effectively, leveraging new spectrum opportunities such as millimeter waves, and utilizing advanced techniques like multi-tower and multi-carrier aggregation.

MORAN, MOCN and GWCN key differences

At present, network sharing predominantly involves components of the Radio Access Network (RAN), such as infrastructure and base station subsystems. Inclusion of core network segments and spectrum in sharing agreements is less common, largely due to regulatory frameworks that seek to preserve distinct network capabilities. While sharing core networks offers cost benefits, they are not as substantial as those gained from RAN sharing. Contemporary standards from the 3rd Generation Partnership Project (3GPP) endorse network sharing among operators and categorize it into three integration levels:

• Multi-Operator Radio Access Network (MORAN) allows for the sharing of equipment only.
• Multi-Operator Core Network (MOCN) encompasses the sharing of both equipment and spectrum.
• Gateway Core Network (GWCN) extends sharing to equipment, spectrum, and selected core network elements.

In operational scenarios, complete RAN sharing is not always practical; operators may opt to retain dedicated RANs in regions with dense traffic. Analysis by some experts in mobile economics suggests that RAN sharing is particularly effective in markets dominated by prepaid services, where increased network accessibility can lead to more chargeable usage and thus, higher revenue streams.

Within the WCDMA framework, active network sharing is attainable via two principal methodologies: Multi-Operator RAN (MORAN) and Multi-Operator Core Networks (MOCN). The distinction between MORAN and MOCN is primarily in the spectrum usage. MORAN operates on individual frequencies allocated to each operator, whereas MOCN utilizes a common spectrum across all operators. MORAN mandates a minimum deployment on two WCDMA carriers, in contrast to MOCN, which can function on a single carrier within constrained frequency ranges. Both frameworks can support concurrent network sharing among up to four operators.

Choosing an optimal WCDMA sharing strategy requires evaluating the benefits of each. MORAN affords greater autonomy, permitting operators to manage their own radio parameters at the cell level, which facilitates service diversification. It also incorporates mechanisms like Flexible-Iu (Iu-flex) for efficient load distribution and shared capacity. Conversely, MOCN offers spectral efficiency benefits, enhancing capacity or coverage, particularly in regionally divided deployments. However, it allows for limited service differentiation and control due to the shared nature of radio resources. MOCN is favored in scenarios where core network entities are shared, typically to fulfill regulatory mandates for rural coverage, whereas MORAN is more suited to urban areas where service distinction is essential. Nokia’s Flexi Multiradio Base Station system module accommodates both dedicated and shared capacity configurations, offering versatility in baseband setups.

How to share MORAN networks

The strategy for sharing fundamentally influences the configuration of network sharing, delineating the commercial, technical, operational, and legal parameters of the collaborative arrangement. Three principal structures underpin network sharing:

1. Formation of a New Network: This approach is optimal for launching a new network generation. Here, sharing entities jointly construct and share the new infrastructure. It is a cooperative effort from the ground up.
2. All-in-One Network Model: A non-traditional form of network sharing, in which one Mobile Network Operator (MNO) serves as the host, providing network infrastructure to the others. The latter forgo their own networks to avail wholesale network services, which may encompass national roaming and Mobile Virtual Network Operator (MVNO) provisions. This model involves reciprocal agreements where one operator builds and operates the network in a specific area while allowing others to roam on it, and vice versa.
3. Consolidated Network Approach: This model emerges when operators merge their existing networks, eliminating redundant sites. Asset management within this structure can take various forms:
   • Joint Venture: Here, the network is co-owned by a new entity created by the MNOs, each contributing resources and sharing control, typically in an equal partnership. Operators essentially become akin to MVNOs utilizing the jointly owned infrastructure.
   • Third-Party Outsourcing: In this arrangement, MNOs transfer their assets to a third party that takes over management and operations. Although this can reduce potential savings due to the cost of outsourcing and may lead to a dependency on Service Level Agreements (SLAs), around a quarter of operators have engaged in such agreements.
   • Network Company: This scenario involves one operator owning the entire network and the others paying for access. It operates as a service company, offering network services to the participating MNOs.

Benefits of Network sharing

The inaugural network sharing pact was established in Sweden, initiated by Telia and Tele2 in the dawn of 2001. Following an unsuccessful bid for a 3G license, Telia entered a joint venture, evenly split with Tele2, enabling Telia to partake in the 3G market sans a distinct license. RAN sharing has emerged as a strategic avenue for operators of moderate and minor scale, including newcomers to the field. It facilitates a hastened deployment of networks, aligning with the swift introduction of new technologies to satisfy regulatory deadlines. Economically, RAN sharing endows Mobile Network Operators (MNOs) with substantial benefits, enabling them to:

• Diminish the aggregate cost of network ownership, which encompasses expenditures on acquisition, installation, operation, and maintenance. The shared access layer yields considerable savings in both capital expenditures (CAPEX) and operational expenditures (OPEX). This encompasses savings on site acquisition, infrastructure deployment, procurement of transmission and radio equipment, and reductions in maintenance and energy expenses.
• Augment revenue streams via expanded service coverage and wholesale agreements, thereby enhancing capital returns.
• Enhance the efficiency in network resource allocation, where spectrum pooling enables expanded bandwidth and improved data transfer rates.
• Mitigate the environmental footprint by minimizing the proliferation of communication towers, thus contributing to more sustainable telecommunications.

Challenges of Network Sharing

In orchestrating a network sharing agreement, four primary challenges merit attention to ensure a fruitful alliance:

1. Autonomy Compromise: In a network sharing scenario, an operator may encounter diminished autonomy regarding:
   • Operational oversight (including handover protocols, key performance indicators (KPIs), and the allocation of baseband capacity).
   • Strategic command over network direction and fiscal commitments.
   • Deployment tactics and the selection of equipment suppliers.
   • The ability to maintain service uniqueness in the face of competitive advancements from partners.
2. Choosing an Associate: The decision of partnership bears significant weight, necessitating careful consideration of:
   • The number of associates, which influences the scale of cost-efficiency, and the geographic overlap of partners’ infrastructure that could lead to additional expenses for eliminating duplicate sites.
   • The potential for differentiation from other partners. An arrangement with a partner possessing a similar network infrastructure is typically more straightforward. Conversely, a partnership with a smaller or less technologically advanced operator could erode competitive edges.
   • Consensus on network progression, deployment schedules, and investment strategies with prospective partners.
3. Regulatory Considerations: The extent of permissible network sharing varies internationally, with regulatory bodies focusing on:
   • Upholding competitive distinction and preventing market collusion.
   • These apprehensions are less pronounced concerning passive sharing.
   • Environmental incentives may sometimes drive network sharing, particularly in underserved rural regions, where regulatory bodies display a more supportive stance.

Each of these challenges requires strategic navigation to balance the benefits of shared infrastructure with the need to retain competitive individuality and operational control.

Summary

The Multi-Operator Radio Access Network (MORAN), or “Split in the eNodeB,” is a network architecture enabling multiple operators to share a Radio Access Network (RAN) node, particularly an eNodeB, along with its resources. In this configuration, each network operator retains distinct core network components, such as the Mobility Management Entity (MME) and Serving Gateway (SGW), among others. Notably, each cell in a MORAN setup is affiliated with one or more Public Land Mobile Networks (PLMNs) as identified in the system’s broadcast information, with shared network cells considered part of all listed PLMNs. The growing interest in RAN sharing, driven by the desire for distinct frequencies or cells, highlights the appeal of MORAN. However, achieving a MORAN configuration faces challenges, particularly due to the 3GPP TS 36.331 specification, which complicates the configuration of unique PLMN identities and necessitates discrete S1 connections for different frequencies or cells, adding to the complexity.

RAN sharing configurations that broadcast multiple cell identifiers resemble the Multi-Operator Core Network (MOCN) model but allow for independent allocation schemes by each operator, unlike MOCN which requires coordinated management of cell identifiers and Tracking Area Codes. This independence in RAN sharing is crucial for operational autonomy and efficient network management.

The advent of 5G networks brings to the fore the necessity to address the surge in mobile broadband traffic, the proliferation of connected devices, and evolving user expectations. Network sharing emerges as a strategic response, facilitating expedited coverage, capacity enhancement, support for higher data rates, and improved end-to-end latency, all while optimizing cost and energy efficiency. It also offers significant capital and operational expenditure savings and fosters innovation by shifting competitive focus from infrastructure to service offerings.

Network sharing’s current landscape primarily encompasses RAN components, with core network and spectrum sharing less common due to regulatory concerns aimed at preserving network capability differentiation. The 3GPP standards categorize network sharing into MORAN, MOCN, and Gateway Core Network (GWCN), each offering varying degrees of equipment, spectrum, and core network element sharing.

Strategies for MORAN network sharing delineate the commercial, technical, operational, and legal frameworks of partnerships, with three primary models: forming a new network, adopting an all-in-one network model, and pursuing a consolidated network approach. These models range from joint ventures and third-party outsourcing to a single operator owning the network, each with its advantages and challenges.

Network sharing’s benefits were notably demonstrated in an early agreement between Telia and Tele2 in Sweden, underscoring its potential to reduce network ownership costs, enhance revenue through expanded service coverage, improve network resource utilization, and minimize environmental impact. However, network sharing also presents challenges, including potential loss of operational autonomy, the intricacies of partner selection, and navigating regulatory landscapes. These challenges necessitate careful consideration to maintain competitive distinctiveness and operational control while leveraging the advantages of shared infrastructure.