CASOPIS REPUBLICKE AGENCIJE ZA TELEKOMUNIKACIJE

ABSTRACT

This study is primarily concerned with access networks, the part of communications networks that connects subscribers to their immediate service providers, and its current evolution forced by the convergence of voice and data, as well as transition to IP architectures. Fixed and mobile telecom operators are facing new competitive challenges as they shift their focus from building networks to developing retail business and content partnerships. In addition, the fierce competitive environment will drive increased merger and acquisition activities, as well as the formation of partnerships between organizations that previously viewed themselves as separate entities. All this tends to increase the importance of the new concept of edge networks as a promising solution. In this document we will set the scope of edge networks reference architecture, describe its key features, and differentiate it from other solutions.

1. INTRODUCTION

Current telecommunication development trends shift the network “intelligence” towards its edge, while the core network remains focused on the capacity expansion and transmission speed. Such development is mainly influenced by the general development of access technologies, both in capacity and variety. The common distinction between core and access networks does not represent the actual situation appropriately. Modern network topology requires an additional network concept which enhances core and access features. This new concept is called the edge network.

Set of available features in consumer electronic equipment for communication applications is highly dependent on the number and performance of the processor devices deployed. Quantity and quality of the processing and storage resources in communication devices have recently been significantly increased. The available bandwidth increased rapidly, both in wireline and wireless access networks. A number of distributed and pear-to-pear applications, together with Internet services such as YouTube and Facebook, rapidly increase importance of the user generated content. Altogether, these trends increase the complexity of the end user communication devices, with regard to both technology and architecture. The new network topology recommends edge networks as the appropriate solution for handling the diversity of multimedia services offered to a plethora of user devices.

Throughout this paper the edge network concept is examined through its typical technology instantiation, the femtocell, a small scale cellular base station which is typically used in residential or small business environments. The femtocell connects to the service provider’s network through the existing broadband infrastructure (such as DSL or cable). It provides voice, data and potential new services in home environment, thus enabling the service provider to extend indoor service coverage and overall network capacity.

2. ACCESS NETWORK TECHNOLOGIES

This paper is mainly concerned with evolution of access network architecture forced by the convergence of voice and data as well as transition to IP architectures. Connecting millions of users to the requested services is not a simple task, it requires people skills and adequate hardware. Traditionally, it has been done through wireline access, still widely used by the following technologies:

Modem technologies
xDSL
Fiber optics
Cable TV
Power line technology

Nowadays, we are witnessing wireless technology becoming more and more important in providing network access, using technologies such as:

2G wireless networks
GPRS
EGPRS
3G wireless networks
HSPA
WiMAX
LTE
WiFi

The access network may be divided into the feeder plant or distribution network, and drop plant or edge network.

Newer wireless access network architectures such as Mobile WiMAX, Mesh WiFi and LTE (SAE) migrate towards flat IP architecture in RAN and in CN, allowing the next-generation base stations to communicate directly with each other and with a centralized network element that provides basic signaling and authentication features. Actually, these next-generation base stations become routers, adding the edge IP network to the overall network architecture. In this way latency is significantly decreased, several network elements are merged together, reducing the overall number of elements and consequently improving the network economics.

Beside wireless networks, the edge access architecture is also evident in relation to converged video services (such as linear TV, TVoD, VoD ) and their provision across wireless and/or wire line access networks.

In this document we will set the scope of edge networks reference architecture, describe its key features which differentiate it relative to other solutions. The reference architecture is intended for wireless and/or wireline network operators who will provide partial or total end-to-end services for their fixed and mobile customer base. This customer base will access the services using wired (xDSL, GPON) or wireless (LTE , WiMAX, MeshWiFi) access networks, and will be able to move between them. This architecture is expected to be cost competitive and capable of supporting a large population of subscribers ranging from hundreds of thousands to millions.

3. EDGE NETWORK CONCEPT AND ARCHITECTURE

Edge networks are unique since they form the boundary between the end user domain and the domains belonging to operators, service providers and enterprises. This boundary has been a persistent source of problems, yet it holds substantial capacity of hosting service intelligence. Edge networks include the user edge, consisting of the devices and resources primarily controlled by the end user, and the access edge, comprising infrastructure and resources controlled by the operator or service provider, but facing the end user.

3.1. Service Edge Architecture

Several trends in network evolution are bringing up the importance of adopting the service edge routing into the overall solution design:

Transition to flat, all-IP networks requires service intelligence to migrate to the network’s edge in support of new, challenging, high-bandwidth, low latency and personalized customer services, such as enhanced VoIP and unicast multimedia delivery,

Rapid evolution of wireless networks from cellular circuit voice networks with supplemental packet data services to true multi-purpose wireless data networks,

Support of session and experience continuity across different access networks that requires new functionalities from the traditional edge router, including policy management supporting individual control of services on a per-subscriber basis for any device, anywhere, anytime, and over any access network (session mobility is the key/unique attribute here for the wireless world – in the past this has been accomplished in cellular networks via purpose-built mechanisms – in the future, we expect it to be more IETF/IP centric),

Convergence of residential and business service edge segments, with the resulting converged service edge market positioned for high-growth (>30% CAGR), as wireline and wireless service providers consolidate.

The service edge is a key mobility control point within the architecture. It provides perimeter security, subscriber event control (authentication, authorization, subscription management), home agent, foreign agent, and traffic policing functions. The service edge device controls the total traffic from all access networks and all subscribers, serving as the single ubiquitous intelligent IP based traffic control point in the network.

3.2. Network Convergence at the IP Edge

The significant need to oversee session management functionality distributed across multiple devices around the edge gateway is becoming a cause for concern as regards the effective management of any access network. The different opportunities and risks associated with distributing this functionality across multiple network elements, or, alternatively, consolidating it into fewer nodes, have often been an essential part of the network planning process. The consolidation option is driven by five fundamental factors, crucial for the process of delivering the new generation of discrete fixed, discrete mobile and converged fixed-mobile IP applications:

Higher scalability of edge network elements,

Network latency,

Highly dynamic nature of the Internet applications environment,

Greater uniformity in edge network requirements,

Smart "Mobile phones" deploys intelligence that goes beyond feature communication devices.

4. EDGE NETWORKS FOR SERVICE CONVERGENCE

4.1. Edge Convergence Architecture

Together with rapid advances in computing and communication technologies, as well as inevitable information e explosion, we are witnessing a proliferation of electronic means for accomplishing an increasing variety of individual and collaborative tasks, through portable or mobile devices.

The edge convergence architecture aims at providing the operator with a decentralized, low cost, scalable solution for delivering voice and multimedia services to his customers. Instead of relying on a costly and complex centralized core network, the architecture pushes the intelligence to the edge of the network, usually by deploying it at the customer premises equipment (CPE) or residential gateway.

The edge provides session control functions and application servers, while the core network is limited to providing AAA services and a gateway to other SIP or non-SIP networks.

4.2. Convergence and Multi Access Edge

Figure 1 shows the variety of consolidation options for the multi-access IP edge, many of which operators have already started to invest in. The five options can be regarded as either autonomous, stand-alone options, or, alternatively, as sequential, interdependent options leading to option 5. Approaches 1, 2 and 4 are already in commercial deployment by leading carriers, while approaches 3 and 5 are not commercially available yet.

Convergence of session management per access network: This is already common practice. Here, the carrier integrates the session management requirements for a single access network into a consolidated platform.

Integration of session management features into the edge gateway per access network: This is already happening today. Here, the carrier integrates a number of session management functions directly into the hardware and software of the edge gateway, thereby completely eliminating the need for a dedicated box for supporting these functions.

A converged session management platform for any network, fixed or wireless: This approach is not in commercial deployment yet. The opportunity here consists of leveraging the convergence of consumer and business requirements across fixed and wireless access networks through a transition to an IP applications environment.

A partially converged edge gateway supporting multiple access networks: Again, this is already happening in both fixed and wireless networks today. Here, the operator makes a break with single-access edge gateways and converges all their fixed access traffic or all their mobile traffic onto a single access gateway.

A fully converged gateway and session management platform supporting any network, fixed or wireless: This approach is not yet in commercial deployment. It enables the ultimate in edge network consolidation by converging the different edge access gateway functions into a single gateway platform capable of supporting any variety of wireless or fixed, consumer or business, connections from a single point in the network.

4.3. What are Femtocells?

This section introduces the technology concept of femtocell. The femtocell is a typical edge network example. The “inverted 4G” concept, introduced here, uses example of the femtocell as the focal point of this paper.

4.3.1. Brief Femtocell Description

Femtocell (Figure 2) is a small scale cellular base station which is typically used in residential or small business environment. The femtocell connects to the service provider’s network through the existing broadband access (such as DSL or cable). It provides voice, data and potential new services within the home environment, thus enabling the service provider to extend service coverage and capacity indoors. A femtocell has the functionality of a typical cellular base station; however, it is extended to allow a large scale, self contained deployment.

In 3GPP, femtocell is also called the Home Node B (HNB). Within the course of increasing the UMTS terminal penetration and fixed-mobile convergence (FMC), an upcoming demand for 3G femtocell is evident. Although most of the interest is currently focused on UMTS, the idea is applicable to all existing and future wireless standards, such as GSM, CDMA, WiMAX, LTE, etc. Moreover, the latest femtocell experience gives an idea how the path of adopting new wireless technologies, usually called 4G, might go from femtocell, i.e. indoor, to public wireless network, i.e. outdoor. This approach, where the new wireless technologies are first adopted and proved within the end user’s premises and only then applied to the public network, is quite opposite to the traditional approach which envisages the femtocell just as the attached extension of the public wireless network. Based on this deployment scenario, the concept is named “inverted 4G”. The femtocell deployment will allow the fix-mobile convergence with existing handsets, while most of the other indoor FMC architectures require a new (dual-mode) handset. The femtocell appears to the standard 3G phone as just another host mobile operator’s cell site, and can be used by almost any phone. The mobile operator’s telephone switch (MSC) and data switch (SGSN) make no difference between the communication with the femtocell gateway and other mobile calls. Therefore, all services, including phone numbers, call diversion, voicemail etc, operate exactly the same way and appear to be the same to the end user.

5. WIRELESS EDGE NETWORKS: INVERTED 4G

Currently, the femtocell concept is aggressively pursued by 3G operators in Europe and Asia, with the objective of increasing UMTS terminal penetration and creating favorable conditions for converged services. A conservative estimate by ABI Research analysts shows that femtocell market could be worth two billion dollars by 2011. This section sums up the state of the art of femtocell technologies and addresses current system level challenges like interference, scalability and remote management.

It also considers economic aspects of using femtocells as outdoor access points. The same attributes that make femtocells ideal for home and office deployment, namely – localized coverage, improved performance, self-configuration, self-optimization, and low cost – can be of use outside, too. This approach, where the femtocells are first used to deliver advanced indoor services and then deployed outdoors, is called the “inverted 4G” concept. Some operators expect the same benefits of increased capacity and better coverage at a lower cost, compared to deploying more macro cell sites.

The dynamic femtocell market continues to grow, as it promises to solve the 3G challenges of coverage, capacity, and churn that are slowing down 3G adoption, as well as deliver innovative supplementary services to the consumer. However, we are at a critical time in the femtocell technology evolution path. Comprehensive understanding of the RF and spectrum engineering complexity introduced by femtocell deployment and corresponding solutions is absolutely critical to mass adoption of the technology. In addition, architectural harmonization will be necessary in order to ensure standardized solution and ultimately drive down costs.

These challenges are being met through a combination of aggressive work within leading femtocell vendors' organizations and communal ecosystem efforts within the Femto Forum. A new technology like femtocells provides not only an interesting value proposition to the consumer and operator, but also a challenging platform for innovation by engineers and marketing experts. Ultimately, it is innovation and wide-scale collaboration that will drive the benefits of femtocells to the consumer.

5.1. Economic and Technology Drivers for Femtocells

The 3 C’s (coverage, churn and capacity) are slowing down 3G adoption. 3G suffers from inadequate indoor signal penetration, leading to poor coverage in the indoor environment where consumers spend two-thirds of their time. To keep the customers satisfied, 3G carriers have increased capacity by constructing additional macro cell sites. However, this strategy is becoming much less attractive.

Because of these challenges, 3G femtocell solutions (Figure 3) are finding new homes for the wireless base stations in consumers’ homes or offices. Femtocells are low power devices combining Node B and RNC functionality, and are self-configuring to minimize interference. Operating as an extension of the carrier's existing network, femtocells enable more comprehensive coverage inside buildings and also at the far edge of the network.

Femtocells also produce cost savings for the carriers. Consumer's home in essence becomes a cell site and there are no site acquisition costs involved. The customer pays for the backhaul by using the existing broadband line. And the electricity bills, which are a large OpEx item for a cell site, are also paid by the consumer. Additionally, femtocells allow the carriers to offload their existing macro-cell networks. Macro cellular network resources that are usually occupied by handling user’s mobile calls, SMS’s, etc. are now freed up as that traffic is handled by the femtocell. These distinct advantages on both sides of the ledger make femtocell a compelling technology choice.

5.1.1. Femtocell vs. UMA

Femtocells have certain advantages over unlicensed mobile access (UMA) and other dual-mode fixed mobile convergence (FMC) solutions. All the components necessary for femtocell deployment are present in many homes and offices today: a standard 3G mobile phone and an IP broadband connection to backhaul traffic to the operator's network. Unlike Wi-Fi, the consumer does not need an upgrade to an expensive, power-hungry, dual-mode handset. With femtocell, any existing 3G handset will work seamlessly. UMA uses unlicensed spectrum which makes it prone to interference and can deteriorate the quality of voice. Femtocells, on the other hand, use the licensed spectrum and provide a standard UMTS access; they leverage the robust channel structures and deliver good quality voice with improved coverage. Seamless handoff from macro cellular network to femtocell and vice versa is already in place, as the existing mobile core network is leveraged to deliver this function.

5.1.2. Wireless Market Macro Trends

Wireless multimedia services will be a key growth area for mobile operators. Mobile video traffic is poised to increase exponentially as usage of high-end mobile devices like smart-phones and tablets ramps up. According to Yankee Group’s Global Mobile Forecast [8] fewer than 600 million smart-phones will be in use in 2010, but that number will more than double in 2014 to nearly 1.4 billion elevating mobile video to 66% of the total mobile data traffic.

5.2. Problems that Femtocells Can Solve

The user-installed device communicates with the cellular network over the broadband connection such as DSL, cable modem, or a separate RF backhaul channel. While conventional approaches require dual-mode handsets to deliver both in-home and mobile services, an in-home femtocell deployment promises fixed mobile convergence with existing handsets. Compared to other techniques for increasing system capacity, such as distributed antenna systems and microcells, the key advantage of femtocells is that there is very little upfront cost to the service provider.

Studies on wireless usage show that more than 50% of all voice calls and more than 70% of data traffic originate indoors. Voice networks are engineered to tolerate low signal quality, since the required data rate for voice signals is very low, 10 kbps or less. Data networks, on the other hand, require much higher signal quality in order to provide the multi-Mbps data rates expected by the users. For indoor devices, particularly at the higher carrier frequencies likely to be deployed in many wireless broadband systems, attenuation losses will make high signal quality and high data rates very difficult to achieve (Figure 4).

This raises the obvious question: why not encourage the end-user to install a short-range low-power link in these locations? This is the essence of the win-win combination of the Femtocell approach: the subscriber is happy with higher data rates and reliability while the operator reduces the amount of traffic on their expensive macro cell network, and can dedicate its resources on truly mobile users.

To summarize, the key arguments in favor of femtocells are the following:

Better coverage and capacity: Due to their short transmit-receive distance, femtocells can greatly lower transmit power, prolong handset battery life, and achieve a higher signal-to-interference-plus-noise ratio (SINR). These translate into improved reception and higher capacity.

Improved macro cell reliability. If the traffic originating indoors can be absorbed into the Femtocell networks over the IP backbone, the macro cell BS can redirect its resources towards providing better reception for proper mobile users.

Cost benefits. Femtocell deployments will offset the need for additional WAN infrastructure and consequently reduce the operating and capital expenditure costs for operators.

Reduced subscriber turnover. The enhanced home coverage provided by femtocells will lessen motivation for home users to switch carriers.

5.3. Why Inverted 4G - Business Case Analysis

The benefits to the customer and the operator are summarized in the Table 1.

Customers with coverage problems for basic voice services will benefit from the presence of the femtocell. All customers that use mobile data will benefit from the higher data rates that the femtocell can deliver. Higher data rates will improve the user experience with data cards or multimedia/smartphone handsets, including applications such as mobile TV, watching video clips (e.g., YouTube) and Internet surfing.

Some customers will be attracted to the enhanced features the femtocell can support. These features include a virtual home number, SMS alerts when someone leaves or comes home, and a variety of converged services planned by the operator’s marketing group.

5.4. LTE and Femtocells

Depending on the perspective, LTE can accelerate the need for femtocells, or femtocells can delay the need for LTE. Regardless of the standpoint, LTE, or, to be more specific, the use of OFDMA and smart antenna technologies, can address some of the potential interference challenges associated with femtocells. The argument for LTE accelerating the need for femtocells is as follows.

LTE will not be a major catalyst for femtocells, although they will play an important role in next-generation networks due to their ability to provide concentrated amounts of data throughput. In fact, HSPA femtocells may actually prove to be a deterrent for next-generation networks, as they will be able to provide concentrated throughput where it is needed, thus fulfilling at least some of the stated objectives of the new networks.

Finally, even within the context of an LTE macro network, the HSPA femtocell would be more than adequate.

6. EDGE NETWORKS: TECHNOLOGY MATURITY

While it may seem slow relative to the number of years it has been talked about, the communications services market is inevitably moving towards Fixed Mobile Convergence of IP-based services. As a general rule, the greater the subscriber number and the greater the number of access networks supported, the greater will be the incentive to converge the networks across both gateway and session management domains.

6.1. Removing Barriers to the Multi-Access Edge

The challenges of implementing approaches of edge network consolidation are already being met in commercial deployment today. A number of important challenges regarding the Converged Session Management Platform for any fixed or wireless network and the Fully Converged Gateway and Session Management Platform supporting any fixed or wireless network, still remain. There are three challenges in particular which need to be addressed:

Overcoming organizational barriers within the carrier:

Aligning industry standards in a way that best supports fixed mobile convergence at the edge of the network;

Overcoming hardware and software design constraints which have traditionally made it difficult to deliver a viable multi-access edge device to the market.

6.1.1. Top five challenges to femtocell deployment

The question now is how quickly femtocell equipment manufacturers and network operators can overcome significant challenges, both technical and commercial, on their way to making femtocell the technology of choice for in-home wireless use. Time-to-market is absolutely critical because Wi-Fi and Unlicensed Mobile Access (UMA) have staked out an early lead in the race for technological dominance. In this section, we list the first five of the top ten challenges to femtocell deployment:

Low-cost implementation,

Network architecture harmonization,

Remote device management and software upgrades,

RF interference,

Potential consumer concerns.

6.1.2. Challenges of integrating femtocells into the core network

Femtocells not only address the capacity challenge, but are also capable of addressing the indoor licensed coverage opportunity associated with 3G, which was earlier limited to high traffic and high worth locations served by picocells. The technology will open the doors to a better user experience and new services, as well as to reducing the cost of voice calls for consumers.

In order to roll-out Femtocell-based indoor coverage services successfully, mobile operators must overcome a few technical challenges, which are broadly categorized in four areas:

Installation, configuration and management of Femtocells,

Radio frequency (RF) planning and interference management,

Integration and inter-operability with the existing macro network,

Inter-operability with and quality of service (QoS) management in the ISP network.

6.1.3. Will the 3G smart phone break the network?

The 2G iPhone posed no major threat to mobile networks as the most data intensive applications, such as media streaming, could only be used over Wi-Fi and therefore the consumer’s own backhaul. The 3G smartphone and tablets revolutionizes the situation by allowing users to access bandwidth heavy applications on the move and, most importantly, use the operator’s backhaul network in the process.

The 3G smart phones pose a far greater threat to networks than feature phones, because its HSDPA data speeds create a far greater load on the network. Backhaul, more than any other area, is being cited as the key solution component that will determine the profitability and success of mobile broadband networks and services. 3G and HSPA technology have created a revolution in cellular radio that transforms the achievable data rates between phones and base stations. However, no such transformation has taken place in the backhaul network. Once the data arrive at the cell tower and start to travel back to the mobile core and the Internet – along the backhaul – they face a significant bottleneck: the existing legacy network architecture with its fixed bandwidth and rigid hierarchy. This is the new mobile broadband bottleneck, and unless it is resolved, the data rates on 3G networks will be throttled and the users of 3G smartphone will have a disappointing experience.

E1s are plentiful and their costs have dropped significantly in Europe in recent years; if higher bandwidth is needed, microwave technology can always be deployed. But whilst this is technically feasible, the business case simply isn’t feasible. However, backhaul technology is well overdue for transformation. Most operators have adopted a strategy of simply adding more E1s, as they never needed to deal with a bandwidth explosion. But, with the growth in traffic being decoupled from the revenue stream, this approach will have to change.

The enhancements in mobile broadband technologies lead to significant changes in the mobile networks eco-system - from voice–centric low capacity architecture to a new world of multimedia services and data oriented network architecture based on IP protocol. The inevitable conclusion is that mobile broadband is expanding rapidly and will continue to grow in the next few years as new technologies are implemented. The consequence of implementing these new technologies is that the capacity required for the transport of these services (the backhaul) will continue to increase in the next few years.

7. EDGE NETWORKS: REGULATORY IMPLICATIONS

Groups that have traditionally been digital “have-nots” are now making dramatic gains. Gaps between rural and urban households and between seniors and younger people have begun to narrow. Some divides, such as that between women and men, have disappeared altogether.

And yet the larger problem persists. Deep divides remain between those who possess the resources, education, and skills to collect the benefit of the information society and those who do not. Persistent gaps remain between different racial and ethnic groups, people with and without disabilities, single and dual parent families, the old and the young, and people with different levels of income and education.

Clearly, the digital divide is much more complex than a mere lack of computers. Simplistic solutions have therefore masked and perhaps even intensified the larger problem. European Commission actively supports the widespread availability of broadband services for all European citizens as laid down in the Lisbon strategy and subsequent Communications [9].

There are two dimensions to the digital divide:

Access is one dimension of the issue. Clearly, people need the basic IT tools, computers and Internet access, at their disposal. But access is only the first component.

The second dimension of the digital divide concerns training, or IT literacy – the ability to use IT for a range of purposes, and the knowledge of how and why IT can be used as a key resource.

Access is a necessary precondition and an access solution based on edge network architecture provides flexibility and scalability needed to effectively address underserved markets, consequently helping regulators and policy makers in their mission to create more equitable conditions for use of broadband technologies. Digital dividend brings about a need for training in order to use the tools. Once people have facility with the tools, they demand content that serves their interests and meets their needs. Inverted 4G approach meets this need as it facilitates use of common cellular applications and tools and their extension to the home environment and underserved markets.

7.1. Regulations for Service Oriented Economies

As economies and value creation are shifting towards service economies it is essential that regulatory aspects evolve too, in order to support further economic growth of a given country. Some analysts feel that the edge approach tends to break down “technology silos” and make regulation (and service) more responsive to end users. The regulatory approach and structure should not be simply limited to telecommunications, but should cover the broad range of technologies that are converging in the ICT arena.

7.2. Net Neutrality

One aspect that requires a careful regulatory approach in order to promote the general concept of edge networks and service economy is the so called “net neutrality”. Regulations surrounding and governing the net neutrality have potential to shape the future of the Internet and the complete IP communication as well. At the moment this paper is published, the issue is still debated. However, the authors do hope for a supportive regulatory framework to emerge and create favorable climate for unimagined possibilities for the communication society at large.

8. SUMMARY/CONCLUSIONS

Edge networks form the boundary between the end user domain and other domains belonging to operators, service providers and enterprises. This boundary continues to be a persistent source of challenges, yet is a right place to host all kinds of service intelligence. Edge networks include the user edge, which consists of devices and resources primarily under the end user’s control, and the access edge, comprising infrastructure and resources under the operator or service provider’s control. The uniqueness of edge networks is in their access network topology and the boundary region introduced to interface the end user domain, including the home network, with WAN and a wide range of service providers, including the enterprise domain. With the introduction of IP services this boundary region is seen as the best place to host additional network and service intelligence needed for the converged user experience.

One good example of more recent technologies that redefines the access networks and forces further evolution of the edge is the femtocell technology. It is a small size cellular base station which is typically used in residential or small business environments. This architecture aims at providing an operator with a decentralized, low cost, scalable solution for delivering voice and multimedia services to its customers without the need for costly upgrades of its core cellular network. The femtocell connects to the service provider’s network through existing broadband (such as DSL or cable) and provides higher data throughputs allowing the service provider to offload its WAN and offer innovative home/enterprise services.

Both the home and office environments contain large amounts of under-utilized computational resources and there is an opportunity to leverage the principles and technologies of cloud computing –virtualization, automation – at the edge, to essentially create a local computing cluster, i.e. a “cloud at the edge”, in order to build richer experiences and run applications that incorporate local user content and context.

In addition to the chosen technology or deployment strategy, broadband wireless operators will need to carefully evaluate their pricing strategies in order to maximize subscriber uptake. The inverted 4G concept enables competitive pricing by relaxing the stress on the cellular core when the traffic patterns evolve towards much higher data usage.

References

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Authors

Dragan Bošković received his bachelor’s and master’s degrees from the University of Belgrade in Serbia and his doctorate degree from the University of Bath in the United Kingdom. He has acquired extensive industrial experience working in various engineering and executive roles for major telecom equipment vendors in UK, France and USA for the past 20 years. Doctor Bošković has amassed 20 patents, and has published several journal papers and position papers on topics including wireless technologies, green engineering, media delivery and cognitive networks. He is often called upon to share insights on these topics at industry events such as the International Consumer Electronic Show, Global Semiconductor Forum, AlwaysOn, Wireless World Initiative and Wireless World Research Forum. Dr Bošković served on President G. W. Bush task force on the Next Generation Networks and currently sits on the Board of Directors for La Citadelle Art NFP and a few smaller privately held technology start-ups. Since 2009 he is a visiting professor of Industrial Engineering and Management at the University of Novi Sad, Serbia.

Milan Kovačević received his bachelor’s (1981), master’s (1985) and doctor’s (1989) degree at the University of Belgrade’s Faculty of Electrical Engineering, Telecommunications Department. In 1982 he started working as a research engineer at the Institute of Applied Physics. Two years later he became engaged at the Institute for Microwave Techniques and Electronics, first as the pilotless aircraft communication system project leader, then as the radar jammer project leader and finally as the system integration lab head. From 1993 till 1996 he held the general manager office at the Intel Computers company, and the following ten years he was the co owner and general manager of the company Infinity Ltd. Since 2006 he is the Deputy Executive Manager of Saga Ltd. Dr Kovačević recently authored two conference papers, “WiMAX in Serbia, New Solution for Access Network“ and “WiMAX, Solution for Alternative Telco Operators“.