Mobility Development Group Newsletter

April 2016
Next MDG Webinar

Wi-Fi Calling: Opportunities and Challenges

Date: May 10, 2016
Time: 9am (pacific), 11am (central), 12pm (eastern)
Presented by: Dr. Necati Canpolat, Sr. Staff Architect, Intel Corporation

This webinar will provide an overview of Wi-Fi Calling (VoWiFi), the benefits of Wi-Fi Calling, business opportunities, end-to-end systems for Wi-Fi Calling, the key technologies and challenges that we need to address in the industry and share what’s ahead.

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Featured Article - Machine-to-Machine Communications and the Internet of Things

Machine-to-Machine Communications and the Internet of Things
By David Crowe, Numbering Administrator, IFAST

Perhaps it was when a bunch of cellular executives sat around and wondered who they were going to sell cellphones to in the near future, when everyone who wanted one had one. “What will we do then?” they said, with a little panic in their voices. Someone had the brilliant idea that the next market would not be “Who?” but “What?” – machines talking to other machines.

Actually, such systems are decades old, but traditionally they were wired. When wireless solutions were used they were not standardized, and devices were not fully customized for their role communicating with machines, not people. A simple example is a thermostat, a device that at least since the 1800s has monitored the temperature of a room or building, and then sent signals down a wire to a furnace or air conditioner to turn it on or off. In cellular systems, there were machine to machine applications even in the days of analog cellular.

The main difference today is that the communications tend to be at a higher level, with much more complex protocols, and also that the communications are networked. Using the furnace or air conditioner example, a protocol today might not just turn the motor on and off, but might also provide maintenance information and alarms. Control over the devices might not just be simply on and off but might modulate the power of the device depending on the current difference between actual and desired temperatures. Access to the information might not just be at the thermostat, if there is one, but on the home owners’ cellphone or tablet.

Nobody knows how many millions of such devices there are today (even getting a precise definition of what an M2M device truly is, is difficult), but whatever it is today, multiply by several orders of magnitude for tomorrow. One recent estimate, by Gartner, is 26 billion devices by 2020.

Networks relying on machine-to machine communications (M2M), also known as the “Internet of Things” (IoT), are generally designed to incorporate multiple transmission technologies, often a mixture of wired and wireless. A pipeline running from an extraction zone to a refinery may use cellular communications for its remote monitoring sites, or satellite communications for those outside any cellular coverage zones, and a mixture of copper wire and fiber communications inside the RF-noisy environment of the industrial complex. Each system will have a unique mix.

Some systems will use wireless technologies out of necessity (such as vehicle monitoring systems) while others will use it simply to avoid the necessity of rewiring buildings to accommodate an ever larger array of networked devices.

Focusing on wireless M2M, the differences between M2M and traditional wireless devices are most important for understanding the impact of M2M on wireless networks.

One of the things that characterizes most modern cellphones is the highly sophisticated user interface for both input (touch or keyboard) and output (large, bright, colored, high resolution screen). If an M2M device even has a user interface it is likely to be very simple, used for testing and installation, and unused the vast majority of time. Many devices will not have a physical user interface at all, they will have to be hooked up to a testing device or to the network to talk to them.

Another characteristic of cellphones is that there is a certain commonality of features driven by current consumer demands. Right now the almost universal characteristics are the large, high resolution screen, a high performance processor, dual cameras, an intuitive user interface and the availability of an application store. But among M2M devices there will be a much larger range of characteristics. Many devices will be custom for specific industry verticals, such as power transmission, health, transportation or oil and gas. Often these devices will be ruggedized or sealed, for long term installation in a hostile environment.

In many cases the M2M device, from the perspective of the wireless network, will just be a consolidator. A variety of devices monitoring an industrial device will be plugged into the M2M communication device, which will facilitate remote monitoring and control via the interfaces that it provides, such as cellular, satellite, WiFi, Bluetooth, Zigbee, fiber and Ethernet.

It might surprise some people to realize that most M2M devices will be very conservative in their data usage requirements. Machine communication tends to be very much more compact than human communications. If I say that, “The door is open”, I might have talked for two seconds, which would be about 20 thousand bits of digitally encoded voice, plus a significant amount of overhead. If sent as a text message, it would be 16 characters, or 128 bits, with a significant amount of overhead. But if sent by a machine to another machine it might only be one bit.

There are many exceptions of course. There are M2M applications that do, at least sometimes, require high data rates, but most often the applications can be satisfied with almost any data technology that it is available today.

The duty cycle of M2M devices is often also very low. A device might summarize data once an hour or once a day, and provide updates upon command or whenever something important changes. This is obviously a lot less usage than your friend (not you, I’m sure) who finds it necessary to text and check their social networks even while crossing the street. M2M devices will not access the internet just because they are bored (although some devices might choose to wait until the network is bored, i.e. void of other traffic, to transmit more efficiently or cheaply).

Power, i.e. battery life, is just as important for M2M as for standard consumer cellphones, although for different reasons. M2M devices may stay in place for many years, perhaps a decade or more, so power is an important consideration. Some M2M applications may have access to power through a cable but because many applications will be remote, and in awkward places (such as on a pipeline or up a tower), more creative solutions will be needed. Solar power or a small windmill, charging a battery, is one possible solution. In other cases a large battery, designed to last weeks or months, can be included, especially in applications where a human will be visiting the site routinely. The power consumption of the device and of the wireless technology will obviously be an important consideration in power constrained M2M applications.

Mobility is a consideration for some applications, such as transportation, and may even require international roaming. But for many other applications the device is relatively static so should stay connected to the same cell and carrier forever. I say, ‘should’ because in practice some locations are going to be in difficult coverage areas and may occasionally switch cells or carriers due to changes in environmental conditions.

Security is a requirement that consumers are now becoming much more aware of, due to the revelations of whistleblowers like Edward Snowden. And it is of critical importance for M2M also, perhaps even more so. M2M devices that control or monitor critical infrastructure must be protected in many ways. Preventing eavesdropping is important not just to protect the proprietary information of the M2M company (such as the amount and type of oil being shipped) but also because customer information will likely also be carried. Imagine if a ring that targeted expensive houses for theft had detailed information about power consumption, and could tell when a house was occupied or not. Or what about information being transmitted within a hospital containing diagnostic test results?

M2M systems also have to be secured from interference with the network, whether this is just a simple Denial of Service attack (bombarding M2M devices with invalid requests to disrupt the network or even to drain the power of the devices) or whether it is actually modifying data. These problems could occur on the backbone network or on the wireless interfaces. Wouldn’t it be tempting to hack into your power company and reset your power meter back about $100 every month? In some cases hacking critical infrastructure could have devastating, even fatal, consequences.

Using the internet as a backbone network offers a lot of cost advantages, but the internet is awash with a variety of threats, from foreign gangsters to domestic governments, apart from the simple unreliability of mixing your critical traffic with people rushing to watch the latest viral video.

All of these considerations affect your choice of wireless technology. First, you need to think not just about today, but about the lifespan of the devices. With 3G systems you need to find out from your carrier how long they will commit to supporting the technology that seems technically best today. Quite a few companies were burned when their 2.5G data devices (e.g. GPRS) were obsoleted by carriers reorienting the spectrum to more modern technologies. On the bright side, 3G systems like CDMA2000 will need to be retained for their voice capabilities, until 4G VoLTE is fully mature, handling all call types. This could mean that 1X data, integrated with 1X voice, is a better solution for low bandwidth M2M than EVDO, simply because EVDO systems are likely to be shut down long before 1X systems.

CDMA2000 shutdowns are estimated to vary from imminent in places where cdma2000 devices are no longer actively sold (such as Canada) to 2021 (as estimated by US Carrier Verizon).

Another choice is to simply jump right away into the shiny new 4G LTE technology. However, these networks still have less coverage. A lot of work is going into creating options within LTE to reduce power consumption. And carriers are racing to match their LTE footprint with their 3G technologies.

These are just some of the considerations for the design of an M2M network. Careful research and analysis of your own requirements will be critical to making the right choices.

About the Author: 

David-BDPDavid Crowe
Numbering Administrator, IFAST

David Crowe has been in the wireless industry since leading the software design for an early wireless switch in the 1980s. Since 1992 he has been a consultant in wireless technology, software design, core network and smart card standards, and identifier systems. He has written for numerous industry publications and published his own newsletter from 1992 through 2004. He can be reached at or +1-403-289-6609.

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Service Provider WiFi Webinar Available on Demand!

Service Provider WiFi: Deploying Unlicensed Access for 4G Mobile Networks
By: Dave Dukinfield, Senior Systems Engineer, Cisco

This webinar discusses how integration of non-licensed WiFi into your EPC for off load or VoIP has been both standardized and deployed in many operator networks.

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M2M Technologies Webinar Available on Demand!

Intro to M2M Technologies: What Wireless or Wired Option is Right For Your Company or Products
By Syed Zaeem Hosain, ‘Z’, CTO, Aeris Communications, Inc.

This webinar reviews the reasons for deploying an M2M and IoT application, the connectivity and technology options available and their characteristics, the future of cellular IoT, and the future challenges for these implementations.

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