This bachelor thesis aims at providing an overview of the evolution process from the current circuit-switched (CS) voice services to those based on the IP multimedia subsystem (IMS). The timeline in question comprises the years 2013 to 2018 and takes into consideration three possible scenarios: one intermediate state and two target states, each of them presenting a particular setting in respect to the CS & IP domain mediation.
Those states are subsequently evaluated according to certain predefined criteria. In addition, a complementary framework is given by the SWOT analysis which will consequently lead to the final recommendations for one of the leading European telecom organizations (the company in question is not disclosed throughout this thesis on purpose). Within this context, the major characteristics of the Austrian as well as European mobile markets are examined. Finally, the expected key assumptions and developments for the given timeframe are presented together with the particular findings of the topics previously described.
As a starting point, the basic IMS architecture is presented together with its major features in respect to other current technologies. In a further step and based on the previous information, the key motivations for the transition from CS to IMS-based voice services will be discussed. In this sense, a service consistency delivered by centralized services on an access agnostic basis is assumed.
For this purpose the initial state is evaluated regarding its three relevant levels: the transport/endpoint, session/control and application/service layers. Next, a more comprehensive approach, the intermediate state, is evaluated: here, the legacy SCP supports the CS&IP domain mediation via the IM-SSF. Moreover, two other target states are assessed involving the SIP AS using a reverse IM-SSF and the L2 interface respectively.
Having highlighted the significant characteristics of each (future) state, attention is then drawn on the various criteria for IMS-based voice services such as roaming, handset capabilities and the like. Hence, a SWOT analysis is presented addressing the question ‘Is the deployment of the intermediate state from a technical and economic perspective recommendable? Finally, the major mobile market characteristics in Europe as well as the expected developments for the timeframe 2013 - 2018 will be described. Furthermore, the concluding recommendations are derived from the key findings throughout this thesis.
Table of Contents
1 Introduction
1.1 Thesis structure
1.2 Motivations behind IMS
1.2.1 Motivations from the operator’s perspective
1.2.2 Motivations from the user’s perspective
2 Overview of the IMS architecture
2.1 Drivers
2.2 IMS horizontal architecture
3 Evolution 2G/3G to IMS
3.1 2G/3G technology features
3.2 Towards IMS
3.3 Intelligent Network (IN) limitations
4 From circuit-switched to IMS-based voice services
4.1 Development path 2013 - 2018
4.1.1 Initial state
4.1.2 Intermediate state based on SCP and IM-SSF
4.1.2.1 Service delivery platform and the Service Broker
4.1.2.2 Service Broker benefits
4.1.2.3 Intermediate state setting
4.1.3 Target state 1 based on the SIP AS and rIM-SSF
4.1.4 Target state 2 based on the SIP AS and the I2 interface
4.2 Analysis criteria for IMS-based Voice services
4.2.1 LTE coverage
4.2.2 Handset capabilities
4.2.3 Service consistency
4.2.4 Roaming
4.2.5 Standardisation
4.3 SWOT analysis
4.3.1 Refarming and the Digital Dividend
4.3.2 Further considerations
5 Major mobile market characteristics
5.1.1 Consolidation trends
5.1.2 Regulation and competition
6 Conclusio
Objectives & Core Topics
This thesis examines the evolutionary transition from legacy circuit-switched (CS) voice services to modern IP Multimedia Subsystem (IMS) based architectures within a leading European telecommunications organization. The central research objective is to evaluate the technical and economic feasibility of implementing specific migration scenarios—an intermediate state versus two distinct target states—within the 2013-2018 timeframe, considering service consistency, market regulation, and competitive pressures.
- IMS architecture evolution and horizontal service integration.
- Technical transition pathways from 2G/3G networks to IMS-based voice services.
- Evaluation of service delivery platforms and Service Broker roles in network mediation.
- Strategic analysis using SWOT methodologies regarding technical constraints and economic profitability.
- Assessment of European mobile market characteristics, including consolidation trends and regulatory impacts.
Excerpt from the Thesis
1.2.1 Motivations from the operator’s perspective
IMS provides an improved approach through the definition of a horizontal architecture (see Figure 2). Here, multiple applications may reuse common functions as well as service enablers. Particularly, the horizontal architecture is well integrated within the current data/voice networks and still provides several advantages coming from the IT domain. In this sense, IMS specifies not only interoperability and roaming, but offers bearer control, charging and security. Hence, IMS can be regarded as a key enabler for the fixed-mobile convergence.
A migration to an all-IP system is at this time taking place within the telecommunications sector. Clearly, the efforts towards cost reduction or the essential need to produce novel services with a positive profit margin represent some of the key drivers. In fact, these objectives apply equally for the fixed and mobile communication. In the same manner, the creation of new business perspectives is fostered since IMS supports the creation as well as deployment of operators’ innovative services (or those coming from third parties).
Consequently, the telecommunications industry may benefit from IMS in the following ways:
A reduced time to market due to the faster development of (IMS) services.
Rise of more lucrative services: the combination of several services in one session, unified billing as well as the SSO (single sign-on) are expected to ‘awake’ user’s interest and thus increase revenue opportunities and customer loyalty.
A more profitable approach for new service deployment: the reduction of the investment threshold becomes feasible based on the uniform service delivery platform.
The combination of applications/equipment from multiple vendors becomes viable for operators.
Migration to new platforms is further flexible and cost-effective.
These advantages are, nevertheless, coupled with challenges for those operators that are progressively transitioning a network. The issue of creating a seamless experience for customers should be given special consideration since the modification of familiar or basic services directly influences the turnover derived from the subscriber base. Furthermore, the issue of how to get more out of existing services while simultaneously finding new revenue sources (based on an improved user experience) should be likewise addressed.
Summary of Chapters
1 Introduction: Outlines the research scope, the transition timeline from CS to IMS, and the overall structure of the thesis.
2 Overview of the IMS architecture: Details the drivers for IMS adoption and the functional advantages of the horizontal architecture over traditional vertical models.
3 Evolution 2G/3G to IMS: Explores the technical progression from 2G/3G systems and identifies the specific limitations of existing Intelligent Networks (IN).
4 From circuit-switched to IMS-based voice services: Provides a comprehensive evaluation of migration pathways, service broker roles, analysis criteria, and a SWOT analysis for the deployment.
5 Major mobile market characteristics: Discusses the broader European market environment, focusing on industry consolidation and regulatory influences on operator strategies.
6 Conclusio: Synthesizes the findings, concluding that the intermediate migration solution is economically recommendable under specific timeframe and acceptance assumptions.
Keywords
IP Multimedia Subsystem (IMS), IMS centralised services, IMS evolution path 2013-2018, Circuit-switched, Packet-switched, Service Broker, IM-SSF, SWOT analysis, Fixed-mobile convergence, 3GPP, Network migration, Telecommunications, ARPU, Service consistency, VoIP.
Frequently Asked Questions
What is the primary focus of this thesis?
The thesis investigates the strategic migration of telecommunication voice services from legacy circuit-switched technologies to the IP Multimedia Subsystem (IMS) for a leading European operator between 2013 and 2018.
What are the key themes addressed in the work?
Key themes include IMS architecture design, service delivery platform optimization, the role of Service Brokers in network interworking, and the economic assessment of transitional network states.
What is the central research question?
The research primarily evaluates whether the deployment of an intermediate IMS migration state is technically and economically recommendable for the specific telecom organization under consideration.
Which methodology is employed for the analysis?
The author utilizes a technical evaluation of network layers followed by a SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) to assess the feasibility of the migration scenarios.
What topics are covered in the main body?
The main body covers the theoretical IMS framework, the technical transition from 2G/3G, specific intermediate and target network states, market characteristics, and regulatory impacts on operators.
How would you characterize this thesis with keywords?
The study is best characterized by terms such as IMS, Service Broker, network migration, fixed-mobile convergence, and telecommunications business strategy.
Why is the "Service Broker" considered a critical component?
The Service Broker acts as a vital mediation layer, allowing operators to leverage legacy network assets while transitioning to new IP-based services, thereby reducing CAPEX and enabling faster service creation.
What does the "Intermediate state" offer the operator?
The intermediate state enables IMS subscribers to access existing GSM/UMTS hosted services, providing a bridge that maintains service continuity while avoiding the immediate need for a full-scale, costly IMS infrastructure.
What role does the Austrian mobile market play in this analysis?
The analysis uses the specific regulatory and competitive environment of the Austrian market, including frequency band auctions and LTE deployment targets, to provide realistic assumptions for the financial model.
What is the final conclusion regarding the migration?
The author concludes that implementing the intermediate solution is beneficial if the net time for profit generation is between 30 and 36 months, given a reasonable customer acceptance rate.
- Quote paper
- MSc. Omar Amoretti (Author), 2013, IMS Centralised Services, Munich, GRIN Verlag, https://www.grin.com/document/454992
