Domain-Specific Reference Modeling in the

Domain-Specific Reference Modeling in the Telecommunications Industry Christian Czarnecki1 and Christian Dietze2 1

Hochschule für Telekommunikation Leipzig, Germany [email protected] 2 Detecon Consulting FZ-LLC, Abu Dhabi, UAE [email protected]

Abstract. The telecommunications industry is currently going through a major transformation. In this context, the enhanced Telecom Operations Map (eTOM) is a domain-specific process reference model that is offered by the industry organization TM Forum. In practice, eTOM is well accepted and confirmed as de facto standard. It provides process definitions and process flows on different levels of detail. This article discusses the reference modeling of eTOM, i.e., the design, the resulting artifact, and its evaluation based on three project cases. The application of eTOM in three projects illustrates the design approach and concrete models on strategic and operational levels. The article follows the Design Science Research (DSR) paradigm. It contributes with concrete design artifacts to the transformational needs of the telecommunications industry and offers lessons-learned from a general DSR perspective. Keywords: enhanced Telecom Operations Map (eTOM); process reference model; process design; telecommunications industry.

1

Introduction

Telecommunications operators are confronted with extensive transformations of market conditions, value chains, and services, e.g., [9], [17], [32, 33]. The Information Systems (IS) discipline contributes with various design artifacts to support the transformational needs of telecommunications operators, e.g., [7], [10], [16], [25], [27, 28], [56]. In this context, reference models are a common approach to generalize knowledge and to offer a point of reference for a whole domain [13]. In the telecommunications industry the non-profit organization TM Forum offers – amongst other content – the domain-specific process reference model enhanced Telecom Operations Map (eTOM) [23], [28], [38]. It was confirmed by the International Telecommunications Union (ITU) as de facto standard [21], and is well-accepted within the whole industry. Its usage has been documented in a broad range of project cases [11]. Hence, eTOM is a domain-specific reference model with a high practical relevance. This article illustrates the reference modeling (i.e., design and application) of eTOM following the Design Science Research (DSR) paradigm [18], [30]. After a discussion of the problem domain, the design and the resulting artifact are described. The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-59144-5_19

Its evaluation is illustrated based on three project cases. In this context, designing concrete models based on eTOM are again DSR projects. Therefore both the reference model and the concrete models are described based on the DSR publication scheme proposed by [15]. The content of this article is based on the authors’ involvements in the eTOM development and project cases. The contribution of this article is twofold. First, the designed artifacts address the practical requirements of telecommunications operators – a major goal of DSR. Second, eTOM and the three project cases can be used as examples for broad design artifacts in the context of general DSR. The structure of the article is as follows: Section 2 briefly explains the research goal and the methodology with respect to DSR. Section 3 describes the design artifact eTOM and its application following the DSR scheme: problem domain containing literature discussion on its relevance (cf. Section 3.1), design method (cf. Section 3.2), artifact description (cf. Section 3.3), and artifact evaluation (cf. Section 3.4). Section 4 discusses lessons-learned and further research steps.

2

Research Goal and Methodology

The topic of this article is the design and application of a process reference model in the telecommunications industry. Reference models are a common research artifact of the IS discipline, e.g., [2], [29], [44], [50], [53]. A concrete model is a solution to a clearly defined situation, while a reference model is a point of reference for a whole range of situations [13]. Subject of this paper is the process reference model eTOM. Various publications show the relevance of eTOM in the telecommunications industry, e.g., [11], [23], [37], [57]. The importance of researching the design process and the resulting design artifacts as part of the IS discipline has been underlined by multiple authors, e.g., [15], [18], [30]. Furthermore, understanding and improving the IS design in practice is a major goal of DSR [15]. This article contributes to DSR by describing the design and application of a domain-specific process reference model that is well-accepted in practice. This article follows the DSR paradigm [18], [30] and proposed DSR publication scheme [15]: (1) problem description, (2) design method, (3) artifact description, (4) artifact evaluation, and (5) discussion and conclusion. With respect to reference modeling both the design of the reference model itself as well as the design of a concrete (application) model based on the reference model can be seen as design artifacts. Hence, the description of the reference model eTOM (cf. Section 3) and the evaluation through the application in three concrete project cases (cf. Section 3.4) follow the above DSR scheme. According to the DSR Knowledge Contribution Framework proposed by [15] the design of eTOM is located in the improvement quadrant, i.e., development of new solutions for a known problem domain (cf. Section 3.1). DSR projects are typically producing design artifacts on different levels of detail, also dependent on the maturity of the design artifact [15]. eTOM is a mature reference model and its application has been discussed in various publications, e.g., [23] explains the initial process defini-

tions, [37] proposes the application of eTOM for a Next Generation Network (NGN), and [57] uses eTOM for an integrated network management system. Furthermore, the details of eTOM are published by the TM Forum [46]. The authors research eTOM from the reference modeling perspective, and selected parts of their work has been discussed in prior publications: [12] discusses the extension of eTOM through reference process flows, [11] provides an empirical study of the eTOM usage, [10] discusses eTOM in the context of NGN, and [8, 9] uses eTOM in the broader context of an enterprise architecture. In this context, this is the first article that summarizes and illustrates the current state of the whole eTOM development from a reference modeling perspective. The own empirical analysis of the eTOM usage [11] shows that its application requires further guidelines. Therefore, this article discusses three project cases that provide exemplary artifacts on a more detailed level. eTOM is continuously updated by the respective working group within the TM Forum. The latest version of eTOM and details about contributing companies and persons are available there (cf. www.tmforum.org). The authors have been involved for many years in the development as part of the TM Forum. The described three project cases are summarized and anonymized illustrations of real-life projects that the authors have accompanied in leading roles (such as project manager). Project cases based on direct observations and official documentations are a valid approach for researching real-life phenomena [58].

3

Reference Modeling in the Telecommunications Industry

3.1

Problem Domain

The telecommunications industry is currently going through a major transformation that impacts strategy, structure, and technology of the players along the whole value chain, e.g., [9], [17], [32, 33]. Understanding the transformational needs and proposing solutions for telecommunications operators are intensively researched with different topical focus, including overall market research [33], value creation and market players [17], [31, 32], [36], [43], [54], structures and processes [6], [12], [34] as well as various functional or technical solutions [7], [10], [16], [25], [27, 28], [56]. The challenges for today’s telecommunications operators can be summarized into (1) changed market conditions, (2) restructured value chains, and (3) new products and services [9]: Looking at the changed market conditions the telecommunications industry is an important part of the ICT sector with a global yearly revenue of approximately 5 trillion USD [33], [43]. Even though the next years forecast a slight revenue growth, the telecommunications industry is a stagnating market. However, the market development differs based on the transmission technology. The total number of fixed telephone subscriptions is declining, and also the growth rate of mobile-cellular telephone subscriptions is decreasing, while mobile-broadband subscriptions have shown a tremendous growth [19]. Those changed usage behaviors are combined with an overall price decrease for most communication services [33], [20]. On the one hand, the increasing demand for high transmission bandwidths requires extensive investments in

network infrastructure, but on the other hand, the transmission itself becomes a commodity. Customers relate the value proposition more with the communication service. Over-the-Top (OTT) providers offer new communication services without owning network infrastructure [14], and create a new competition for traditional telecommunications operators. Some new services offered by OTT providers have even replaced equivalent communication services – for example, WhatsApp has replaced the traditional Short Messaging Service (SMS). While the pure transmission business is stagnating, there is a growth potential for telecommunications operators in vertical markets, e.g., automotive, banking, healthcare, insurance, transportation and logistics as well as smart home [9]. In summary, from a market perspective telecommunications operators have to combine more customer orientation with increased efficiency. The restructured value chain is influenced by new market players [31], [35]. Technical transmission becomes a minor part of the overall value chain, which is now confronted with new players, mergers, and acquisitions [42], [55]. The convergence of communication services [4], new mobile devices (i.e., smartphones) with high performance operating systems [1], and virtual business models [36] are impacting the value creation. The telecommunications value chain evolves into a value network consisting of network operators, software intermediaries, financial intermediaries, content providers, portals, and resellers [26]. For traditional telecommunications operators the shift from usage-dependent to flat-rate tariffs was the starting point for a complete rethinking of their business models. A possible strategic option is the combination of transmission services with application services, which allows differentiated pricing and new revenues (e.g., advertisement). For traditional telecommunications operators own developments, acquisitions, or partnerships with new market players are required, which leads in most cases to a fragmented value creation. New products and services are strongly linked with the changed market conditions and value creation. For example, a smartphone generates more than 14 times the data volume of a basic mobile phone [49]. Telecommunications operators are confronted with continuous innovations [32] and shorter product development cycles [6]. Convergence on the application as well as on the technology side impacts the production structure [52]. For example, the strong link between the telephone network and the assigned telephony service is no longer valid. Nowadays Internet Protocol (IP) services realize telephony services independent from the transmission network. Hence, a flexible coupling between application services and transmission services is required. Furthermore, the commercial perspective of a communication product should be differentiated from its realizing services [6]. Both require a complete rethinking of product and production structure of traditional telecommunications operators [6], [10], which is related to an abstraction from technical complexity and flexibility of the production. In practice, telecommunications operators have been adapting their strategies, structures, and technologies due to the described industry changes [6], [42], [55]. Therefore, a need for domain-specific reference solutions supporting those transformations has been arisen. In this context, the industry organization TM Forum offers reference models for the telecommunications industry [23], [28], [38]. The TM Forum is an international

well-accepted non-profit organization and was founded by major telecommunications operators. Today, it has more than 900 member companies that range from communication service providers to software vendors and system integrators. With working groups, workshops, and conferences it provides an ecosystem for joint development and research activities. The TM Forum is headed by a board of directors. Membership is open to companies and research institutes. Members can contribute in the working groups and use all the provided content in their companies’ projects. The TM Forum offers the following three references for processes, data, and applications [45]: 1. enhanced Telecom Operations Map (eTOM), provides process definitions and process flows based on a hierarchical structure [46]. 2. Shared Information/Data Model (SID), provides a data structure and detailed entity relationship models (ERM) [47]. 3. Telecom Application Map (TAM), focuses on functionalities for applications [48]. Challenges Value Chain Value creation Partnering

Market Products & Services Competitors Technologies Market potentials Customer requirements Economic conditions Innovations Regulation

Telecommunications Operator

Requirements     

Customer orientation Flexibility of production Abstraction from technical complexity Fragmented value creation Efficiency increase

TM Forum Reference Models  Customer-centric processes  Decoupling between product, service, and resource  Domain structure differentiating between customer, technology, and product  Infrastructure-independent operations  Implementation through standard software systems

Fig. 1. Summary of problem domain (upper part according to [9])

With respect to the discussed challenges and requirements those TM Forum reference models support telecommunications operators through customer-centric processes and consequent decoupling between market requirements and technical realizations. The proposed models differentiate between product, service, and resource. They are combined with clear process domains, and therefore those reference models help to increase flexibility and generalize from technical complexity. Furthermore those reference models are applied by industry-specific standard software systems. This interrelation between challenges, requirements, and TM Forum reference models is summarized in Fig. 1. For the reference process model eTOM a more detailed explanation is provided in Section 3.3.

All three reference models are continuously updated in working groups belonging to the TM Forum. They reflect a consensus within the industry. Furthermore, the ITU has confirmed parts of the TM Forum reference models as de facto standard [21, 22]. This publication focuses on the process reference model eTOM. The application of eTOM is described in various publications with different topical scope [12], [23, 24], [28], [37], [40], [57]. Furthermore, an own analysis of 184 transformation projects in the telecommunications industry shows an extensive usage of eTOM [11]. In this context, this article contributes a comprehensive description of eTOM, its development, and its application with a clear link to DSR. 3.2

Design Method

The design of eTOM follows an iterative process that is mainly based on contributions by member companies based on their experiences in practice, i.e., requirements from the problem domain. The eTOM working group discusses in regular conference calls as well as during on-site workshops those contributions (e.g., Team Action Week). The whole development follows a hierarchical structure. All new contributions or changes are mapped to the high-level structure (eTOM level 0-1). Furthermore, general design principles have been defined as a common basis [46]. Those design principles, e.g., define that eTOM “is decomposed from notional Level 0 to more granular levels – Levels 1, 2 and 3 (and some of level 4)” [46] and that “the goals, inputs, outputs, and activities of decomposed Process Elements at a lower level are consistent with the higher level” [46].

reference framework construction

Problem Domain

value delivery

Application Model completion

Reference Model

Fig. 2. General reference model design method ([9] according to [41])

From a general perspective, the real value of a reference model can only be observed after using it in a concrete implementation [5]. In this context, [41] has described an iterative design process that uses the experience with the reference model application as input for the further development (cf. Fig. 2). The iterative development process of eTOM is comparable with this general approach [9]. The specific requirements of the telecommunications industry (problem domain) as well as the concrete experiences with the application of eTOM are used as input for a continuous development by the TM Forum. The high-level eTOM structure can be seen as reference framework, while the regular contributions and updates are constructions and completions according to this structure. Furthermore, the design method includes an evaluation that is mainly based on a consensus within the TM Forum [12]. First, the development team decides that a concrete design artifact is ready for its publication, i.e., the artifact has reached “team approval”. Second, the whole eTOM working group – consisting of industry representatives – evaluates the artifact. Third, a technical committee of the TM Forum checks the overall quality and consistency of the new artifact. Fourth, the new artifact is provided to all TM Forum members for their comments. During the whole evaluation process changes are documented and incorporated in the artifact. Afterwards, the design artifact is officially published as part of the next eTOM version which is available through the TM Forum website. 3.3

Artifact Description

The core elements of eTOM can be structured into (1) process definitions which provide a collection and categorization of business processes specific for telecommunications operators [23] and (2) reference process flows which propose a sequence for those process definitions [12]. Both are structured in a hierarchical manner on different levels of detail (cf. Fig. 3) [9]. Each part of eTOM contains specific design artifacts, e.g., on level 0-1 a process framework is proposed and on level 3 detailed reference process flows are provided. Those design artifacts are interrelated with each other, e.g., the process definitions level 3 are categorized according to level 2 and used as input for the detailed reference process flows on level 3. Furthermore, eTOM contains various methodical guidelines, a general concept description, and application notes describing specific implementations. Hence, eTOM consists of many different documents, an XML-based representation and model files in various formats. The eTOM process definition distinguishes on the highest level the following three process groups [23]: 1. Operations contains all processes that are required to run a telecommunications operator under the assumption of existing infrastructure and products. Those processes cover, e.g., sales, after-sales, incidents, and billing. 2. Strategy, Infrastructure and Products (SIP) cover all other domains-specific processes that are a necessity for a telecommunications operator – i.e., planning and implementing its infrastructure and products from strategy development to technical realization.

3.

Enterprise Management provides general supporting processes, e.g., human resource management, finance, and communication.

Fig. 3. Structure of eTOM artifact

The process groups Operations and SIP cover the industry-specific content that is required for the core value creation [9]. Both are further horizontally structured by the involved entities [23]: • Market summarizes the general view of market requirements and opportunities. • Products are service capabilities combined with commercial offers. They are sold to customers. • Customers are the interface to individual consumers or business entities that are interested in or have bought products. • Services are a logical view on capabilities that are relevant to sell products. • Resources provide a technical realization of services. • Suppliers/partners might deliver capabilities with respect to products, services, or resources. The three process groups Operations, SIP, and Enterprise Management are combined with the six horizontal entities from the eTOM framework (level 0-1). Based on this structure process decompositions are provided (cf. left part of Fig. 3). Hence, the

process definition of eTOM is a hierarchical collection of business processes. For a concrete process design, this collection can be used as a common terminology as well as a checklist to identify all relevant processes. However, the process definitions proposed in the initial eTOM publications (i.e., GB921-D and GB921-DX) do not include any reference for a process flow, i.e., they do not make any statement about the sequence. As part of the continuous development of eTOM (cf. Section 3.2), reference process flows were developed [12]. The reference process flows are published as an official extension to eTOM in GB921-E. The reference process flows are based on the following domains providing an endto-end perspective on the process sequence [8, 9], [12]: • Customer-centric domain contains all interactions that are directly initiated by the customer. • Technology domain includes the realization and operations of communication services and network resources. • Product domain ranges from product development to product elimination. • Customer domain covers interactions that deal with customers but are not directly initiated by the customer (e.g., marketing campaigns). • Enterprise support domain includes general support processes (e.g., finance or human resource management). For each domain, end-to-end process flows are defined. These end-to-end process flows are then mapped to eTOM. With this mapping the sequence is added to the process definition. Furthermore, the reference process flows are defined on different levels following the eTOM hierarchy (cf. right part of Fig. 3). The customer-centric domain, for example, contains the end-to-end process flow Request-to-Answer that covers all process steps from the customer contact to the answering of the request [8, 9], [12]. By combining the hierarchical process definitions with end-to-end process flows, eTOM provides an extensive process reference model for telecommunications operators. Through its hierarchical structure, it can be used for strategic and planning purposes as well as for operational implementations. With the end-to-end process flows, interrelations between organizational and technical entities are transparent. 3.4

Artifact Evaluation

Even though the evaluation is an indispensable part of DSR [18], the evaluation of a reference model is a methodical challenge [39]. The reference model should be generalizable for a certain problem domain, and its application is decoupled from its development [41], [51]. Hence, its general validity cannot be proven, however it becomes more likely with each application [3]. The application of a reference model can be illustrated through project cases which are seen as a valid evaluation of design artifacts [18]. The focus of this article is on the evaluation of the eTOM process reference model through real-life project cases. It follows an illustration of three project cases. All three cases were accompanied by the authors and are illustrated here in a summarized

and anonymized manner. Their descriptions are based on direct observations and official project documents which are valid methods for researching real-life phenomena [58]. Project Case 1: Improvement of Problem-to-Solution Process. Purpose and Scope. Subject of this first project case is a well-established telecommunications operator in the Middle East. It offers fixed line and mobile products. The former monopolist faced increased competition combined with declining customer satisfaction. The telecommunications operator started an extensive transformation program. The improvement of the Problem-to-Solution process was part of this program and integrated in a broader Business Process Management (BPM) project [8, 9]. Project Approach. First, the existing processes related to problem reporting, analysis, and resolution were analyzed. Second, an improved target process was designed and implemented. In both parts eTOM was used as a reference. During the analysis the process framework (level 0-1) supported the identification of relevant processes and their interfaces. Based on the process framework interviews with responsible persons were conducted in order to understand the currently implemented process. For the target process design the detailed charts of the eTOM reference process flows (level 3) were used as starting point. They were mapped to the organizational structure and adapted according to specific requirements based on workshops with the responsible persons. Some process parts were further detailed on level 4. Artifact Description. As a result detailed target processes were designed for the Problem-to-Solution process. In total, 35 detailed target process charts were developed. All target processes were based on the process reference model eTOM. Fig. 4 shows an example of a detailed target process (level 3). Artifact Evaluation. The target Problem-to-Solution process was implemented within a project duration of 8 months. In comparison to the initial situation concrete performance improvements were measured one month after process implementation. For example, the working hours related to the process were reduced by 39%. Furthermore, the total number of reported incidents was decreased by 23% due to faster problem resolution and less repeated problem reports. The evaluation of the long-term performance development would require further studies that are not planned so far.

Problem-to-Solution (eTOM Level 2)

Target Process (Level 3)

Fig. 4. Exemplary illustration of project case 1

Project Case 2: Implementation of a Network Operations Center. Purpose and Scope. Subject of this second project case is an African telecommunications operator offering fixed line and mobile products. Due to historically grown network infrastructures, a new overall Network Operations Center (NOC) was implemented. One part of this implementation was the design of target processes for the NOC. Project Approach. The project was structured into three phases. In phase 1, the existing processes were collected and analyzed. Phase 2 covered the definition of a high-level framework for the target processes. In phase 3, detailed processes were designed and mapped to the existing organization. In all three phases eTOM and especially the reference process flows of the technology domain were used as a reference.

Fig. 5. Exemplary illustration of project case 2

Artifact Description. As a result, a complete process design from level 0 to level 5 was developed for the NOC implementation (cf. Fig. 5). The reference process flows of the technology domain from eTOM were adapted based on the specific requirements. On level 3-5 process definitions and process flows provide a clear mapping to organizational responsibilities on an operational level. Furthermore, detailed Key Performance Indicators (KPI) were defined. Artifact Evaluation. All designed target processes were discussed and agreed with the persons responsible for the execution of these processes. After the NOC implementation, the TM Forum assessed all NOC processes as part of an eTOM certification, which is a formal assessment conducted by TM Forum assessors that were not involved in the project. As a result the quality as well as eTOM compliance of all target processes were confirmed. Project Case 3: Improvement of Network Operations Processes. Purpose and Scope. Subject of this third project case is a European telecommunications operator with own fixed line and mobile infrastructures offering telecommunications products for consumer and business customers. A strategic program was launched to improve the current network operations. As a part of this program, the processes related to network operations should be harmonized. As a first step a high-level concept for this endeavor was developed.

Project Approach. The eTOM framework level 0-1 was used as starting point. Specific requirements were collected, evaluated and mapped to eTOM. The identified processes and requirements were discussed with the responsible persons and summarized in a highlevel concept. Artifact Description. The result contains a process framework (level 0-1) with a definition of all relevant core processes (cf. Fig. 6). The definition included a detailed description as well as a mapping to the organizational structure. Those core processes were based on the reference process flows of the technology domain. Furthermore, support processes and the interfaces were identified based on the eTOM framework.

Fig. 6. Exemplary illustration of project case 3

Artifact Evaluation. The designed results were confirmed by the responsible persons and the steering committee of the overall program. In a next step, the outcomes were used for the planning and implementation of the improved network operations. This task also included more detailed process flows and operational process implementations. However, the implementation is still work in progress.

4

Discussion and Outlook

This article describes the design and application of the domain-specific process reference model eTOM. Following the DSR paradigm, it contributes to the development of new solutions for the known problem domain telecommunications industry.

As starting point, the requirements of the telecommunications industry are summarized. eTOM is a mature design artifact that is well-accepted in practice. Both the design of eTOM as well as the resulting artifact are illustrated. As an evaluation three projects are described that apply eTOM in a practical context. Also the illustrations of those three projects follow the DSR paradigm and are structured accordingly. Due to the complexity of the topic, the explanation of eTOM is limited to an abstract level, and the illustrations of the project cases provide summaries of selected parts. Further details would be required to apply the results in practice. From the perspective of the telecommunications industry the article proposes domain-specific artifacts for the current transformational needs. Both the process definitions as well as the reference process flows provide reference solutions on different levels of detail. The project cases illustrate the usage of eTOM on strategic and operational levels. The examples show the identification and mapping of the different parts of eTOM to solve concrete practical problems. The following lessons-learned for using eTOM in a practical context can be summarized: • Selection of relevant eTOM parts is essential. eTOM covers all possible processes on different levels of detail. Based on the concrete project situation only selected parts of eTOM are relevant. • Interrelations between eTOM parts have to be considered. There are various interrelations within eTOM which are not always directly visible. For example, the process definitions do not include a sequence which is provided by the reference process flows. • Mapping to organizational structure is a prerequisite for implementation. eTOM provides reference processes independent from organizational structures. Therefore, the organizational mapping is part of the customization while designing a concrete model. From the perspective of general DSR the article provides examples for a domainspecific reference modeling, i.e., design process, resulting artifacts, and evaluation. Reference models are well-accepted contributions of the IS discipline to practical problems. Based on the exemplary experience with eTOM the following lessonslearned for general research on design science can be summarized: • Illustration of comprehensive design artifacts is a challenge. In practice, design artifacts are typically complex, e.g., the process definition of eTOM encompasses several hundreds of pages. • Evaluation of reference models requires further guidelines. The project cases show that the application of eTOM is related to different parts and require specific customizations. Hence, the evaluation with project cases is mainly related to the applicability. With respect to the continuous enhancement of eTOM, the presented results can be used in future developments. Especially the experience with ongoing virtualization of network operations (project case 3) as well as the harmonization of operations processes due to technical innovations (project cases 1 & 2) are important inputs for eTOM. In addition, future research could be related to the following questions: What

is the relation between eTOM processes and different types of organizational structures? How is a concrete model derived from eTOM, and which interrelations (also between processes, data, and applications) should be considered? How can those concrete project cases be used for the evaluation of reference models? These questions are a starting point for further research on domain-specific design artifacts supporting the practical transformational needs in the telecommunications industry as well as general research on guidelines for designing and evaluating reference models in the context of DSR.

5

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