This paper provides an assessment of wireless BB services drawing on Telstra's experience as an operator. It discusses the evolution of wireless technologies and the drivers for the building of Telstra’s Next G® network, including the role devices have played. It also considers the growth of mobile service capability and future trends, such as the growth of both high bandwidth video services and low bandwidth but high volume Machine to Machine or M2M communications. Issues such as latency, interoperability and quality of coverage, and data usage per device are discussed. Finally the development and deployment of portable wireless broadband base stations for use in disaster areas and for locations of temporary increased demand is described.

 

Introduction

The term ‘broadband’ is generally used when referring to a high-speed data service, typically a data service with download speeds of several hundred kilobits per second (kbps) or more. It was first used for fixed (or wired) services to distinguish between dial up access (tens of kbps) and early digital subscriber line (DSL) services (256kbps or greater).

With the most advanced wireless networks now supporting peak network download speeds towards 100Mbps the term ‘broadband’ truly applies to wireless, hence the term ‘wireless broadband’. However to fully understand the impact of wireless broadband on the personal and business lives we lead we need to look beyond speed alone.

Wireless networks first transformed voice communication by enabling calls to be made and received at a time and location that is convenient to the customer. The same is now the case for data communications. This drives a different customer behaviour compared to a fixed service and as a consequence a different business model is required from an operator to satisfy the customer service requirements.

This paper looks at the evolution of wireless technologies and the drivers for the building of Telstra’s Next G® network, including the role devices have played. It also looks at the growth of mobile service capability and future trends, such as the growth of both high bandwidth video services and low bandwidth but high volume Machine to Machine or M2M communications.

Next G® A new beginning

In 2005 Telstra decided to build a high speed wireless network using advanced third generation High Speed Packet Access (HSPA) technology, later to become known as the Next G® network. At this time the most widely used data application was SMS or ‘Short Message Service’ – still the case in many countries today. SMS has since changed from primarily being a communications means between two people, to being a business enabler used in applications as diverse as interactive voting for television shows, for sending reminders about a doctor’s appointment or a library book being due, your bank keeping you informed of your credit card balance, or for an airline to send you a boarding pass. In other words, SMS has become a rudimentary form of data communication.

Telstra recognised at the inception of Next G® that for data services to become a core part of a wireless business then data performance and capability required the same, if not greater, attention as voice services. Up until then data performance was seen as secondary to voice, with key network measures focused on voice coverage, voice call set up success and voice call drop rate.

With the launch of the Telstra Next G® network in 2006, Australia had its first truly national wireless network to support wireless broadband services as well as voice services. Using High Speed Downlink Packet Access (HSDPA), the network initially offered peak network downlink speeds of 3.6Mbps. From its launch, the Next G® network offered coverage that was deeper and wider than that on either of the existing second generation GSM or CDMA networks.

A critical aspect of the Next G® network performance has been the backhaul transport network used to connect base stations to the core network and on to their final destination. In the GSM networks this was often limited to one or two 2Mbps links. This was suitable for voice and low speed data services but not sufficient for transmitting HSDPA broadband to a base station. Telstra recognised this limitation early and decided that base stations should be connected via optical fibre wherever practical, with alternative transmission only being used where it was uneconomic to deploy fibre.

It was further recognised that as the radio network technology would develop to support even higher speeds, so too the backhaul capability would also need to increase. Hence, Telstra has upgraded its backhaul networks from being ATM based to being Gigabit Ethernet based, with high capacity sites able to support speeds greater than 100Mbps. As at May 2011 more than 90% of the Australian population have access to base stations served by Ethernet backhaul.

In order to meet the increasing customer demand for data services Telstra has continued to be at the forefront of global technology with the introduction and continued development of the HSPA technology. This technology has been successively stepped over time through a technology evolution supporting peak downlink network speeds from the original 3.6Mbps, through 14.4Mbps, 21Mbps, and presently 42Mbps using Dual Channel HSPA+ technology (DC-HSPA+). Coincidently, introduction of High Speed Uplink Packet Access (HSUPA) supports peak network uplink speeds of 5.8Mbps in the Next G® network.

As a further step in this evolution, in September 2011 the network capability was enhanced with the introduction of the latest step in the technology roadmap, fourth generation Long Term Evolution (LTE) functionality. In addition to increasing the capability of the network to carry the growing data traffic, it has enabled Telstra to demonstrate new wireless broadband services that take advantage of the higher speeds and lower latencies including full high definition video conferencing, which requires at least 4Mbps on both the uplink and downlink.

Whilst 3G HSPA+ dual channel technology is capable of supporting typical download speeds ranging from 1.1Mbps to 20Mbps, using the Telstra USB LTE mobile broadband modem, customers in LTE coverage areas can achieve typical download speeds ranging from 2Mbps to 40Mbps and upload speeds ranging from 1Mbps to 10Mbps. The upload speeds achievable on the LTE network are around three times faster than previous generations of mobile broadband in Australia.

Figure 1 - Speed increases over a decade

It is not just the Speed - Latency is also important

As mobile data services evolved from email and text based browsing (using WAP Mark-up Language or WML), to more interactive experiences such as social media and with the richer HTTP based sites commonly accessed via a PC, the latency (delay) of the network has become more important. Services such as games and VoIP require consistently low latency, and these services are being more frequently accessed from the wireless network than previously.

For example, web pages can require many interactions between the customer’s device and the host site to display the entire page, with each interaction impacted by the latency of the connection.

The wireless industry has recognised the importance of minimising latency, with each evolution of the standards introducing changes to improve this aspect of operation.

Given the importance of latency to customer experience, Telstra measures the latency of the Telstra network as shown in Table 1. The Telstra network latency is only one component of the latency experienced by the customer with other networks, software applications and service providers beyond Telstra’s control all contribute additional latency, therefore typically a user would experience latency beyond the figures quoted.

Network Technology	Typical Download Speeds	Typical Upload Speed	Latency
GSM GPRS	30-40kbps	10kbps	~500ms
3G EDGE	75-90kbps	30-40kbps	~500ms
3GSM UMTS	180-280kbps	60-330kbps	~300ms
3G HSPA 3.6	550kbps - 1.5Mbps	300kbps-1Mbps	~100ms
3G HSPA 14.4Mbps 7.2/1.9 Rated Devices	550kbps - 3Mbps	300kbps-1Mbps	~100ms
3G HSPA 14.4/5.8 Rated Devices	550kbps – 6Mbps	300kbps-3Mbps	~100ms
3G HSPA+ 21Mbps ELITE & other 21/5.8 rated devices	550kbps - 8Mbps	300kbps-3Mbps	~100ms
3G HSPA+ [Dual Channel] 42Mbps ULTIMATE 42DC/5.8 rated devices	1.1Mbps - 20Mbps	300kbps-3Mbps	~100ms
4G LTE (1800MHz)* 4G USB Broadband Modem *Will seamlessly switch over to the highest available 3G speeds outside 4G coverage areas.	2Mbps – 40Mbps	1Mbps – 10Mbps	~30ms

Table 1 - Technology vs speed/latency capability

Quality Coverage is important

Prior to the launch of Next G®, Telstra operated two cellular networks based on different standards (CDMA and GSM). Whilst this was acceptable for voice, it was difficult to provide a consistent data solution to meet a customer’s needs in all Telstra coverage areas. Customers had to make the decision at the time of purchase as to what was important to them. Customers who wanted good regional and rural performance would need to choose CDMA, while those who required primarily urban coverage would safely choose GSM. The two networks were not interoperable, meaning that customers could not roam across them. Moreover these networks were designed primarily for voice with data as an additional service.

With the launch of the national Next G® network this was no longer an issue. The Next G® network provides a greater breadth of coverage in the rural and regional areas than the CDMA network, and greater depth of coverage than GSM in the metropolitan areas – providing a ‘one network, one customer’ experience.

Telstra has continued to expand both the breadth and depth of the Next G® network coverage, with the network now covering more than 99% of the population and more than 2.1 million square kilometres. At the same time Telstra has both increased the radio access network capabilities and upgraded the connectivity to the core network to enhance the customer experience.

When Telstra launched its 4G/LTE network it made sure that it was fully backwards compatible with the existing 3G/HSPA+ network, so that customers can seamlessly switch over to the Next G® network if they move from a 4G coverage area.

Figure 2 - NextG network (click image to enlarge)

The Next G® ecosystem – beyond the network

Device technology, like the network, has evolved rapidly and with it customer expectations. The main devices available in 2006 were ‘feature phones’, which were essentially phones designed for voice and SMS communications. They typically had a low-resolution colour screen and a camera that supported 0.5-1M pixels. There were however signs of the future, with most phones supporting music download and playback, email and MMS.

Since 2006, Telstra has launched approximately 280 Next G® devices including:

• 153 Next G® handsets and PDAs,

• 33 Next G® data cards and USB modems, and

• 94 Next G® modules, routers, telemetry devices and embedded laptops.

In 2011 alone, Telstra has launched approximately 70 new wireless devices.

With improvements in technologies, the capabilities in wireless devices offered today more resemble compact computers. The most popular hand held devices are smartphones, with high-end devices supporting dual core CPUs running up to 1.5 GHz with embedded Graphic Processing Units. These devices are capable of delivering not only voice and text, but also high quality multimedia and access to social networking sites like Facebook and Twitter.

The phones have become multipurpose devices featuring a touch screen replacing the keypad, video recording, editing and playback upto1080p HD, a still camera with up to 16M pixels and Stereoscopic 3D, GPS, a digital compass, accelerometer and gyroscope; and with HDMI, USB 2.0 and WiFi high speed connections.

	LG Tu 500 -2006	Nokia N95 - 2007	Samsung Galaxy S II -2011
Display	TFT, 65k colours	TFT, 16M colours	Super AMOLED , 16M colours
Size	176x220 pixels	240 x 320 pixels	480 x 800 pixels,
Internal memory	16 MB	160 MB storage, 64 MB RAM	16GB/32GB storage, 1 GB RAM
Connectivity	HSDPA 1.8Mbps	HSDPA 3.6Mbps	HSDPA, 21 Mbps; HSUPA, 5.76 Mbps
		Wi-Fi 802.11 b/g, UPnP technology	Wi-Fi 802.11 a/b/g/n, DLNA, Wi-Fi Direct, Wi-Fi hotspot
Camera resolution	1.3 MP, 1280 x 960	5 MP, 2592 x 1944 pixels, LED flash	8 MP, 3264x2448 pixels, LED flash
Video	QVGA (320 x 240) @ 15fps	VGA (640x480)@30fps	1080p@30fps
CPU		Dual ARM 11 332 MHz processor; HW Graphics Accelerator	Dual-core 1.2 GHz ARM Cortex-A9 processor, Mali-400MP GPU, Samsung Exynos C210 chipset
Other		GPS	GPS, Digital compass
		Image viewer	Image/video editor
		Document viewer (Word, Excel, PowerPoint, PDF)	Document editor (Word, Excel, PowerPoint)
			Google Search, Maps, Gmail,
			YouTube, Calendar, Google Talk, Picasa integration

Table 2 - Smartphone features

Data-centric devices have also evolved over the same time, with the initial Next G® devices being PCMCIA based data cards capable of 3.6Mbps peak speeds. Both the capabilities and form factors have evolved – Telstra now not only offers PC-centric USB dongles, but also WiFi hotspots and embedded modules. Smartphones are also becoming personal WiFi hotspots, enabling a small number of devices to share their network connectivity via tethering. LTE-capable devices supporting average user speeds of up to 40Mbps have also been launched.

Device performance is also important

The importance of device performance cannot be overstated in a mobile environment. Whilst many now talk about screen resolution or camera size, the critical aspect when it comes to customer satisfaction is the performance of the device on the network. Can a call be completed, or can the required data be sent and received?

Telstra recognised this early in the development of the Next G® network and in 2007 instituted a world-first device accreditation program, known as the ‘Blue Tick’. Each device that is approved by Telstra is tested not only to ensure that it meets the minimum performance requirements, but also to gauge sensitivity at the very fringes of coverage. If a device is rated as having significantly better performance in fringe coverage then it is given a blue tick and promoted as such.

This continues to be the only such program that assists customers who either live in, or travel to, more remote regional areas in selecting the most appropriate handset for their coverage requirements. A video on how Telstra tests handsets can be found on YouTube by searching for ‘Telstra Blue Tick’.

Data usage per device is also growing

Since launch, data usage on the Next G® network has been doubling approximately every 12 months and industry forecasts predict that this it is set to continue for at least the next few years.

Figure 3 - Forecast data usage

This is due not only to an increase in customer numbers, but by customers continuing to use more data. With the increasing capabilities of the devices on the wireless network video usage is a big driver of this growth.

The Cisco Visual Networking index survey forecasts the number of online video users increasing to approximately 1.5 billion in 2015, up from about 1 billion in 2010. This increased video usage will drive the global mobile Internet data traffic up, with total traffic expected to increase by over 26 times between 2010 to 2015. This is significantly higher growth than the general Global IP growth, which is expected to be 4 times the 2010 traffic levels by 2015.

The increased usage of video is expected to grow from about 50% to about 66% of mobile data traffic.

The connected future

There is little doubt that mobiles have been the boom technology of the past decade. According to the GSM Association (GSMA), mobile service numbers have grown globally from 1 billion in 2001 to over 5.8 billion in 2011.

Further to this, research commissioned by the GSMA shows that the number of connected devices is expected to be more than 24 billion by 2020, from 9 billion today, and mobile connected devices (ie those capable of connecting to wide area networks like Next G®) will make up half of these, ie 12 billion by 2020. A connected device refers to any addressable device that could be connected to a network. It includes both fixed devices like PCs and mobile devices such as handsets, tablets, eReaders, etc. It also includes devices such as remote sensors, remote monitoring and actuating devices.

Similar growth levels are predicted in other industry research, such as the Cisco Visual Networking index which forecasts that there will be 15 billion connected devices by 2015.

To put these numbers in perspective, a forecast from Gartner in 2008 showed that, based on growth trends at the time, there would be 2 billion PCs by 2014.

A lot of the growth in device numbers is being driven not only by the traditional consumer oriented devices, but also by embedded devices being used for machine-to-machine (M2M) communications.

Machine-to-Machine (M2M) is defined by ETSI in Technical Specification ‘TS 102 689’ as “the communication between two or more entities that do not necessarily need any direct human intervention”.

M2M applications can vary greatly in both the amount of data they transmit and how often they are active e.g. a taxi sending a small location update back to base every few seconds versus an electronic billboard that downloads new video to display once a day.

A small subset of the applications and industry segments that will benefit from M2M deployments is shown below.

Monitoring & Control	Agriculture
Asset Tracking	Transport
Public Signage	Transport
	Retail Advertising
Vending / Ticketing	Kiosk
Security	Monitoring
Health Care	Monitoring
Other -	AMI (Smart Meter / Grid); Security (CCTV & Personal); Consumer Electronics; Telematics Asset Tracking (Mining) Electronic Payments

Many of the applications and services in the M2M space, such as utilities, telematics, mobile health and automotive, depend on highly reliable and secure solutions and reliable connectivity.

When considering M2M and the impact on an operator there are several different factors to take into account compared to consumer-oriented services:

• High Number of M2M Devices:

• The sheer volume of processing their provisioning, billing and control signalling will place a strain on wireless network elements.

• M2M Data Traffic Profile:

• This does not necessarily have the same behaviour as traditional human generated voice calls and data traffic.

• Mixing Human and M2M Traffic:

• While at the same time not degrading the performance of the network for existing “human” customers.

• How many M2M can a wireless operator support...?

• The answer depends heavily on the traffic profile of each M2M application/service and the mix of these applications/services in the network, the resulting radio state used to transfer data, the mix of the M2M traffic, network resources consumed by non-M2M traffic, network timers, etc

A large number of devices regularly transmitting a small amount of data (for example a heartbeat) can have a significant impact on the network resources.

CoWs can fly

As the reliance on wireless communications has grown, so has the need for operators to find innovative techniques to providing solutions for situations that require either temporary coverage or capacity expansions. To meet this requirement Telstra has produced bespoke transportable mobile network base stations called a Cell on Wheels (CoWs).

Telstra uses CoWs during high profile events to provide additional capacity, and in times of emergency such as natural disasters, to ensure continued coverage. Telstra’s ‘herd’ of CoWs are fitted with all current mobile technologies and can usually be established within a couple of days to meet demand and maintain mobile traffic.

The first CoWs were designed and built to be transported on a truck or trailer. These required a fixed network backhaul connection (e.g. copper or optical transmission) to enable the transportable solution. This was not practical in all scenarios as the backhaul did not always exist, or may have been damaged in the natural disaster eg. floods washing the cable away, or fire damaging the cable. In response, and to ensure Telstra can provide the best possible service to customers even in the most difficult times, Telstra developed the Satellite CoW for instances where no backhaul is available.

The first such solution was a fully collapsible system that could be transported in a 4WD, by helicopter or by commercial freight, and could be assembled in approximately 2 hours by two trained technicians.

Since this original concept additional solutions have been developed providing Telstra with a fleet of flexible solutions to meet the needs of customers

• Flyaway or light vehicle – 4Mbps satellite backhaul

• Lightweight Trailer – 8Mbps Satellite Backhaul (Flyaway version permanently mounted on a trailer with larger fixed satellite dish)

• Satellite Backhaul Trailer – 8Mbps Satellite Backhaul (Traditional cable backhaul COW with a satellite dish mounted on the front of trailer)

Figure 4 - Examples of CoWs installations and transport

All at Sea

The reliance on mobile communications is not limited to land. In May 2010, Telstra announced the launch of new online maps to enable seafaring Next G® customers to check the mobile network’s coverage out to sea. The Next G® network’s high speed mobile broadband data capability means boating enthusiasts and professionals can quickly access a wide range of important marine services such as weather reports, tide information, high resolution maps, fish prices, shipping information, access to email and more.

In addition to the Next G® network’s terrestrial coverage, the Next G® network covers more than 1 million sq km out at sea. The Next G® network coverage can typically extend 20 to 70 kilometres out to sea from mobile base stations located near the coast. These include popular boating areas such as the Great Barrier Reef, the Sydney to Melbourne coast and the Whitsunday Islands.

As with land-based coverage, a variety of factors influence network coverage and performance at sea such as the tides, swells and other weather conditions.

Conclusions

The evolution of the cellular network capability from the early analogue networks, through to the current 3G and 4G digital networks, has allowed the services that customers use to evolve from voice, to include text (SMS) and low speed data, and from there to today’s web based multimedia experience, with online browsing and video streaming. At the same time device capabilities have evolved to support a large range of new services and in doing so have integrated many features that used to be delivered by stand-alone devices.

With many customers migrating their voice calls from fixed to mobile access, the pervasiveness and capabilities of wireless connectivity have also enabled many customers to use wireless data as well as fixed connections for data.

As customers have come to depend on the wireless networks for not only their voice communications but their data connectivity as well, operators have had to change their business behaviours and provide a service that is both reliable and has the depth and breadth of coverage required by the customers for both voice and data. Key performance indicators have also evolved from those that supported voice communications to include measures for data service performance.

With the increasing capability, reliability and coverage of wireless data networks, opportunities for new uses of the networks are being opened up with machine-to-machine communications likely to rapidly evolve.

Operators will need to continue to evolve their networks to ensure they continue to meet their customer expectations, and to do this they must embrace both new technologies and new implementation techniques.

 

Acknowledgements

The author would like to acknowledge the contributions of Paula Rujak, Stephanie Manning, Stephen Howell, Anthony Goonan, and Jenni Barbour.

 

References

Gartner. 2008. Press Release: Gartner Says More than 1 Billion PCs In Use Worldwide and Headed to 2 Billion Units by 2014 Available from: http://www.gartner.com/it/page.jsp?id=703807

 

Cite this article as: Swadling, Michael. 2012. ‘Wireless broadband – An operator perspective’. Telecommunications Journal of Australia 62 (1): 12.1-12.11. Available from: http://tja.org.au.