In its initial phase, all of the internet's IP addresses were assigned to computers of one sort or another. Some of these were servers, and a growing number were clients that mostly consumed (but could sometimes modify) content on those servers.
As the internet — and in due course the worldwide web — developed, more kinds of (increasingly mobile) computing devices became connected, and web servers delivered ever richer content with which they could interact. Although this first internet/web revolution changed the world profoundly, the next disruptive development, in which the majority of internet traffic will be generated by 'things' rather than by human-operated computers, has the potential to change it even more.
There's many a slip between
a potential brave new technological world and a reality that could improve the quality of life of a significant proportion of humankind.
This 'Internet of Things' (IoT), or more prosaically 'Machine to Machine' (M2M) communication, is well under way — after all, microprocessors are to be found in all manner of 'things': domestic white goods, cars, credit cards, your passport, your family pet, the CCTV camera in your street, the lift (elevator) in your office and many more. Add the magic ingredient of internet connectivity (or the ability to be read by an internet-connected device), bake with applications and services that make use of the data gathered by this vastly expanded network, and you've cooked up another technology revolution.
As the authors of the excellentput it: "The data are no longer in the computers. We have come to see that the computers are in the data".
However, as the aforementioned book discusses at length, there's many a slip between a potential brave new technological world and a reality that could improve the quality of life of a significant proportion of humankind. Whether the Internet of Things comes to pass in a satisfying way will depend critically on how the emerging M2M ecosystem is architected.
The anatomy of M2M
Any new field comes with its own concepts and jargon, so it's useful to map these out as clearly as possible: our taxonomy is outlined below.
A point worth stressing is that data transfer patterns in the M2M-driven Internet of Things will differ fundamentally from those in the classic 'human-to-human' (H2H) internet. M2M communications will feature orders of magnitude more nodes than H2H, most of which will create low-bandwidth, upload-biased traffic. Many M2M applications will need to deliver and process information in real time, or near-real-time, and many nodes will have to be extremely low-power or self-powered (eg. solar powered) devices.
The 'things' in the IoT, or the 'machines' in M2M, are physical entities whose identity, state (or the state of whose surroundings) is capable of being relayed to an internet-connected IT infrastructure. Almost anything to which you can attach a sensor — a cow in a field, a container on a cargo vessel, the air-conditioning unit in your office, a lamppost in the street — can become a node in the Internet of Things.
These are the components of 'things' that gather and/or disseminate data — be it on location, altitude, velocity, temperature, illumination, motion, power, humidity, blood sugar, air quality, soil moisture... you name it. These devices are rarely 'computers' as we generally understand them, although they may contain many or all of the same elements (processor, memory, storage, inputs and outputs, OS, software). The key point is that they are increasingly cheap, plentiful and can communicate, either directly with the internet or with internet-connected devices.
All IoT sensors require some means of relaying data to the outside world. There's a plethora of short-range, or local area, wireless technologies available, including: RFID, NFC, Wi-Fi, Bluetooth (including Bluetooth Low Energy), XBee, Zigbee, Z-Wave and Wireless M-Bus. There's no shortage of wired links either, including Ethernet, HomePlug, HomePNA, HomeGrid/G.hn and LonWorks.
For long range, or wide-area, links there are existing mobile networks (using GSM, GPRS, 3G, LTE or WiMAX for example) and satellite connections. New wireless networks such as the ultra-narrowband SIGFOX and the TV white-space NeulNET are also emerging to cater specifically for M2M connectivity. Fixed 'things' in convenient locations could use wired Ethernet or phone lines for wide-area connections.
Some modular sensor platforms, such as Libelium's WaspMote (left), can be configured with multiple local- and wide-area connectivity options (ZigBee, Wi-Fi, Bluetooth, GSM/GPRS, RFID/NFC, GPS, Ethernet). Along with the ability to connect many different kinds of sensors, this allows devices to be configured for a range of vertical markets.
Server (on premises)
Some types of M2M installation, such as a smart home or office, will use a local server to collect and analyse data — both in real time and episodically — from assets on the local area network. These on-premise servers or simpler gateways (right) will usually also connect to cloud-based storage and services.
Local scanning device
'Things' with short-range sensors will often be located in a restricted area but not permanently connected to a local area network (RFID-tagged livestock on a farm, or credit-card-toting shoppers in a mall, for example). In this case, local scanning devices will be required to extract data and transmit it onwards for processing.
Storage & analytics
If you think today's internet generates a lot of data, the Internet of Things will be another matter entirely. That will require massive, scalable, storage and processing capacity, which will almost invariably reside in the cloud — except for specific localised or security-sensitive cases. Service providers will obviously have access here, not only to curate the data and tweak the analytics, but also for line-of-business processes such as customer relations, billing, technical support and so on.
Subsets of the data and analyses from the IoT will be available to users or subscribers, presented (hopefully) via easily accessible and navigable interfaces on a full spectrum of secure client devices.
M2M and the Internet of Things has huge potential, but currently comprises a heterogeneous collection of established and emerging, often competing, technologies and standards (although moves are afoot here). This is because the concept applies to, and has grown from, a wide range of market sectors.