The ‘Internet of Things’ is fast becoming a part of everyone’s lives. More and more gadgets and devices have the ability to connect to some type of network. Some networked devices being brought to market today did not seem plausible even five years ago, for example livestock monitoring systems, power outlet switches, toaster ovens, pill bottles, plumbing systems, sprinkler systems, bathroom scales, and thermostats, to name a few. For devices without this capability, many system designers are thinking about the limitless possibilities of a connected smart device, whether they connect to the Internet or interact with a local network. When it comes to future designs, network functionality is quickly changing from a luxury feature to a must-have capability.
Market research firms have attempted to forecast the rapid growth of connected devices. IHS iSuppli estimates that by 2015, Internet-enabled consumer devices—connected devices outside the traditional personal computing space of desktops and laptops—will reach 780 million units, significantly exceeding the expected shipment of PCs which is estimated at 480 million units.1
There are many challenges to developing a network-connected device, but one common element to every one of these designs is the requirement for a unique hardware address in every device. This hardware address is necessary to properly communicate on the network as it uniquely identifies the incoming and outgoing data from that specific device. Let’s examine the challenges of bringing connected devices to market, particularly with respect to the manufacturing flow and cost control.
Unique identifiers Hardware addresses must be globally controlled to ensure they are unique, but what actually comprises a hardware address value? There are two types in use today. For networking hardware such as wireless routers, the unique hardware address required for communicating on local networks is 48 bits long and is often referred to as a media access control (MAC) address or abbreviated as MAC-48. In devices with network access such as printers and multimedia equipment, along with software like those used in virtualization technology, the hardware address is called an extended unique identifier (EUI) and can be 48-bits or 64-bits long or abbreviated as EUI-48 or EUI-64. The term “MAC address” is used synonymously with both types of values as they are assigned from the same numbering space.
The range of available MAC/EUI addresses is, in part, controlled by the Institute of Electrical and Electronics Engineers (IEEE). The IEEE registers and assigns a 24-bit organization unique identifier (OUI) to a company; this 24-bit OUI value in turn becomes part of the MAC/EUI address. The fee to register for and be assigned an OUI by the IEEE is $1,750. Purchasing a range of addresses from the IEEE represents a fixed cost that must be considered in a development budget. The OUI value starts every MAC/EUI address starts, followed by a 24- or 48-bit extension identifier that, when combined, creates a 48-bit MAC/EUI-48 number or a 64-bit EUI-64 number (see figure 1).
Figure 1: MAC and EUI addresses start with the organization unique identifier (OUI), followed by a 24- or 48-bit extension identifier.
One OUI registration will give the registrant about 16 million potential 48-bit values or over 1.1 trillion 64-bit values. To prevent waste of available MAC/EUI addresses, IEEE will not assign a new OUI value until at least 90% of the registrant’s original allotted values have been used.