IEN: Can the limitations of wireless technology be overcome?

Stein: While wireless networks are perceived to have limitations in regard to reliability, security, and robustness, many advancements are in process that will remove these constraints. For example, reliability is improved by the use of mesh network topologies that allow data packets to be transferred via redundant paths. The use of frequency agility algorithms greatly reduces the potential for nulls in the radio space, and advancements in encryption standards are making wireless networks as secure as their wired counterparts.

IEN: How much progress has been made in preventing software and hardware debugging issues? Installation challenges?

Stein: Self-healing wireless mesh networks greatly simplify installation challenges. Using this architecture, the installer simply places the nodes of the network where data need to be transmitted or received and the network will automatically form. Issues surrounding setting of address, routing, and configuration are completely eliminated. Wireless mesh networks are also extremely scalable as the self-forming and self-healing characteristics of the network support the dynamic adding and removal of network nodes.

IEN: What advances do you see in open standards and data sharing?

Stein: New open standards will advance the use of computer networks, especially wireless networks, in a variety of new and different applications. The objectives and benefits of open standards, however, will differ depending on the market. For example, the WiFi open standard allows consumers to choose hardware components from multiple manufacturers with the confidence that they will be interoperable. In the industrial market, however, vendor interoperability is likely to be a lower priority as customers are more likely to deploy a network from a single vendor. In this market, the benefit of open standards is more likely the ability to segment the problem into discrete and manageable elements that will allow data to be shared across different systems.

IEN: How about production management, collaborative manufacturing, plant intelligence and visibility?

Stein: A major advancement in networks used in the management of production and factory automation is the advent of wireless network technologies that are specifically designed for these harsh environments. These advances include both new open industry standards, such as the IEEE-802.15.4 that specifies the Physical and MAC layers of the network, as well as Zigbee, a Network Layer Standard.

Using a wireless sensor network in a production management provides several major benefits, including:

• Dramatically lowering the cost of network installation, as wires and conduit need not be deployed.


• Substantially shortening the amount of time needed to deploy the network.


• Offering new opportunities for the monitoring of production properties, since the costs to install a monitoring network is greatly reduced.

Realizing the full benefits of a WSN, however, requires integrating the wireless sensor network with the factory's legacy systems. For example, WSN can provide data that are used as input into existing MRP systems, as well as complementing DCS and other factory automation systems.