Abstract
The tremendous growth in the mobile communications sector has had a profound technical, economic/business, and social impact in Europe and worldwide (Chochliouros & Spiliopoulou, 2005). In particular, various sectors’ effects combined with the rapid expansion of (fixed) broadband wireless technologies have generated, in several instances, suitable prerequisites (and/or conditions) for further development and exploitation, to successfully realize a diversity of convergencebased opportunities (Chochliouros, Spiliopoulou, & Lalopoulos, 2004; Yoon, Yoon, & Lee, 2005). Mobile devices are currently used in virtually every domain of human activity (i.e., private, business, and governmental). While the relevant penetration levels are likely to continue to enlarge (in fact, mobile phone penetration has now reached well over two billion subscribers globally), the most important future evolutionary progress will be the development of innovative broadband facilities-applications. Potential offerings of third-generation mobile (3G) infrastructure (and of its enhancements), together with other modern wireless technologies, especially Radio Local Area Networks (RLANs) and Wi-Fis (Kumar, 2004; Siau & Shen, 2003) affect the growth of the modern economy. The fast expansion of these technologies creates a paradigm shift that will make possible the appearance (and the adoption) of new data services, able to combine the advantages of broadband with mobility features (Commission of the European Communities, 2004a). To this important perspective, all related applications can exercise an essential impact in various fields (technical, commercial, financial, regulatory, social, etc.) and, most significantly, they can produce considerable economic effects by potentially modifying the way that business is done. However, as most of the innovative electronic communications offerings can be accessed and exploited by converged means and resources, the “combined” usage of fixed and mobile infrastructures/facilities can be the basis for further development and progress. Moreover, if looking forward, the convergence of telecommunications-, broadcasting-, and Internet- based facilities will result in the proliferation of high-speed multimedia services, delivered over such networks/infrastructures. Recent market experiences have demonstrated that 2.5G/3G infrastructures (and RLANs) will coexist and provide complementary services (Commission of the European Communities, 2004b). Users can thus benefit themselves of high-speed wireless access when near a hot-spot, and receive 3G services over a broader area. Therefore, convergence of fixed and mobile services, through unified fixed/mobile offerings, is expected to bring additional opportunities for novelty.
TopUnlicensed Mobile Access In The Context Of The Broader “Convergence” Efforts
As voice becomes even more of a commodity service and use of data services grows, network operators realize that they need to adopt converged (network-based) services and offer easier ways to roam across networks (Sutherland, 2007). The world scenery for wireless and mobile communications is changing very quickly (subsequent to international trends and practices) and consequently, a number of market operators of the wider electronic communications industry have nowadays focused their business priorities on the applicability/effectiveness of an increasing set of fixed-mobile convergence (FMC) initiatives (Merry, 2007), linked with modern and fascinating technological solutions (Lainé, Drevon, & Cannet, 2005).
The majority of these initiatives are expected to be suitably developed through the exploitation of “Unlicensed Mobile Access” (UMA) (or alternatively known as “Generic Access Network”-GAN) technology, which represents the first global standardized effort (supported by the 3rd Generation Partnership Project - 3GPP) for subscriber access to mobile circuit-, packet-, and IMS-based (IP Multimedia System) services over any IP-based access network (e.g., Wi-Fi, DSL (Digital Subscriber Line), Cable, Fiber-to-the-Home (FTTH), etc.), including the Internet (More specifically, the related system was initially called “UMA” and then renamed to “GAN”).
Key Terms in this Chapter
RLAN (Radio Local Area Network): It is a local area network (LAN) using radio instead of wires. A LAN is a user-owned and -operated data transmission facility connecting a number of communicating devices (e.g., computers, terminals, word processors, printers, and storage units) within a single building or floor.
Seamless: Free from noticeable transitions (i.e., no end-user action is required; speech interruptions are short; service interruptions are short; incoming calls are not missed; packet sessions are maintained; services work identically).
Generic Access Network (GAN): It is a local area access technology that enables GSM and WCDMA (Wideband Code Division Multiple Access) service to be delivered over broadband and WLAN, at homes or in offices. End users can enjoy the same service as in the wide area network.
IMS (IP Multimedia Subsystem): It is a standard that defines a generic architecture for offering multimedia services over any IP network. IMS specifies interoperability and is well integrated with existing voice and data networks, while adopting many of the key characteristics of the IT domain. It enables converged voice and data services in the mobile environment, built on Internet services, applications, and protocols.
Fixed-Mobile Convergence (FMC): It is currently one of the crucial strategic issues in the telecommunications industry. It is the way to connect the mobile phone to the fixed-line infrastructure. With the convergence between the mobile and fixed-line networks, telecommunications operators can provide services to users irrespective of their location, access technology, and terminal. This encompasses a wide range of services; however, they generally have the core of allowing the user or the network to take advantage of higher-speed, cheaper local unlicensed access networks in local environments for lower-value, high-volume transactions, such as cheaper calls or downloading larger files from home or office, while using the scarcer licensed spectrum for higher-value, lower-volume transactions, where customers are prepared to pay the mobile premium of licensed spectrum.
Handover: It refers to the ability for the subscriber to have an active session in progress (e.g., voice call) and be able to move from one domain to another without the session being interrupted or requiring manual intervention from the subscriber to reestablish a session.
QoS (quality of service): Measurement of transmission rates, error rates, priority, dedicated bandwidth, and other parameters relating to performance of data networks.
GSM (Global System for Mobile Communication): A second-generation mobile system originally developed in Europe, using a time division multiple access (TDMA) radio interface combined with frequency division multiple access (FDMA); it is oriented to voice and circuit mode data.
Unlicensed Mobile Access (UMA): It is the 3GPP global standard for subscriber access to mobile circuit, packet, and IMS-based services over any IP-based access network, including the Internet. With UMA, mobile operators can now leverage the cost and performance advantages of IP access technologies (e.g., DSL, Cable, Wi-Fi) to deliver high-quality, low-cost mobile voice and data services in the locations where subscribers spend most of their time.
VoIP (Voice over Internet Protocol/IP): It refers to a class of technologies that enable the routing of voice calls over the Internet or any other IP network. VoIP is not a service, but a technology enabler used to implement services.
WLAN (Wireless Local Area Network): A generic term for different high-speed radio access modes in the 2.4 GHz to 5 GHz frequency bands.
Wi-Fi (Wireless Fidelity): Commonly-used synonym for WLAN; Wireless Fidelity is a popular term for wireless local area networks operating under IEEE Standard 802.11b in the 2.4 GHz range.
Mobile Virtual Network Operator (MVNO): is a company that provides mobile phone service but does not have its own frequency allocation of the radio spectrum, nor does it have all of the infrastructure required to provide mobile telephone service. MVNOs are roughly equivalent to the “switchless resellers” of the traditional landline telephone market. Switchless resellers buy minutes wholesale from the large long distance companies and retail them to their customers.