Ethernet: A Cost-Effective Enterprise Link
Ethernet is linking office systems to industrial applications, enabling enterprise-wide information access.
by Rob McKeel
Ethernet is an open-architecture protocol that has evolved since the early 1980s from the original 10 Megabits per second (Mbps) version to newer 100 Mbps and 1 Gigabit per second versions. The availability of high-speed Ethernet, along with advances in switching technology, message prioritization and topology, are increasingly making Ethernet a top choice for installations in industrial environments as well.
The benefits of enterprise-wide Ethernet to manufacturers are numerous and include: infinite scalability, ease of use and commonality benefits associated with implementing one network rather than multiple networks throughout a facility, ready availability of components and the ability to operate over a variety of cabling types.
But there's an additional benefit to implementing Ethernet both at the fieldbus level and at the enterprise level: Ethernet networks are more cost effective.
It starts with infrastructure
Ethernet has the largest installed base of networks in the world, primarily as office LANs (Local Area Networks). The many cost advantages that result when a technology is in such widespread use makes Ethernet a welcome option for the factory floor.
Since Ethernet has been the office networking choice for many years, components are produced in very high volumes -- resulting in lower prices. Simply stated, the greater the supply, the lower the price. Contrast this with lower-volume proprietary networking components: The lower the supply, the higher the price.
In addition to lower prices, higher volumes mean readily available products. Because Ethernet networks are built and maintained with these readily available, off-the-shelf components, users don't have to worry about network downtime that can occur as a result of waiting for parts to be delivered -- delays that can cost a company substantially in lost production time.
Installation costs are also lower because network configuration is less complex and extensive for Ethernet than for proprietary fieldbus networks. Despite organizations like ODVA (Open Device Vendors Association) and others that set standards for fieldbus networks, problems still exist with interoperability among network devices, from setup to maintenance, due to their proprietary nature. As a result of trying to overcome these interoperability issues, configuration of network addresses, devices and data is much more complex and extensive on a proprietary fieldbus network. Because Ethernet is a completely open standard, connectivity and interoperability among devices are not ongoing problems. Much of the network configuration is automatic; for example, switches "learn" types of information and where to route it, and then know when and where to pass along information after the first transmission.
Ethernet can also work with existing proprietary technologies as an overlay system, which allows manufacturers to avoid the cost of ripping out and replacing legacy proprietary networks. Most manufacturers already have Ethernet networks for their office systems, so in many cases the existing office Ethernet installation can be expanded to and adapted for the factory floor.
Because of Ethernet's widespread use and lower-cost devices, companies can also be assured of affordable future expansion. Ethernet offers users an infinitely scalable system, with an unlimited number of nodes available along a network that can support devices from any vendor, enabling manufacturers to pick and choose the devices they want to use. Proprietary systems, on the other hand, support only a limited number of network nodes and those devices designed specifically for use along that network. This limits the manufacturer's ability to choose devices based on any number of factors, including technical sophistication, speed and cost.
Trimming training costs
In addition to lowering the costs of the infrastructure itself, implementing Ethernet throughout the enterprise lowers the costs of training workers who use and maintain the network.
When an enterprise has standardized on one network, workers throughout the facility have to be trained only on that network rather than on multiple networks. As a result, companies have to pay for only one training course, rather than for several, minimizing the costs of upfront and continuing education. And, because workers are required to learn only one network, they have the opportunity to learn that network more thoroughly -- maximizing its capabilities and efficiencies.
Since proprietary networks are not as widely used, the technical knowledge base is generally much smaller. For example, one engineer may have worked on a plant's proprietary network for many years but that worker is the only one in the plant who understands and maintains the network. When that worker leaves the company, the company's knowledge base is gone, too.
Not so with Ethernet. More workers -- probably even within a manufacturer's existing staff -- are familiar with Ethernet and how to use and maintain the network. Since many workers are already familiar with Ethernet, the amount of overall training time needed is even further reduced. The loss of one staff member does not entail the loss of the company's knowledge base.
Connecting for cost savings
While many manufacturers have connected their office systems, their business partners and their customers, the factory floor is typically disconnected from the rest of the enterprise. This is changing with the advances in industrial Ethernet. Ethernet can now serve as the factory-to-enterprise network, allowing manufacturers to obtain and strategically use real-time data about their processes and operations. This capability reduces costs -- whether Ethernet is used throughout the operation, from the offices to the plant floor, or as an overlay interconnection solution to link proprietary factory fieldbus networks to the office systems.
Savings are derived from Ethernet's seamless integration with the Internet. Ethernet is a primary enabler for Web-based technologies because most Ethernet-based networks use TCP/IP (Transmission Control Protocol/Internet Protocol) as the communications protocol. They thus facilitate the use of key Internet tools -- browsers, Web servers and e-mail servers. Using TCP/IP over an industrial Ethernet network, companies can better exploit applications such as Enterprise Resource Planning (ERP), Vendor Managed Inventory (VMI) and remote monitoring via a standard Internet browser. These applications reduce costs in various forms, from more efficient resource management to lower travel expenses.
In conclusion, Ethernet delivers distinct performance advantages at a low cost relative to those of proprietary networks. This unique combination of benefits can ensure that the network becomes equally as prevalent throughout the enterprise as it is currently in the office.
About the author
Rob McKeel is the vice president of operations for GE Cisco Industrial Networks. He formerly served GE as a manager of communications and motion development for GE Fanuc Automation, a leading global supplier of automation controls and a joint venture between GE and FANUC Ltd., and he held several management and project management positions within GE. McKeel received a B.S. in electrical engineering from North Carolina State University, an M.S. in computer science from the University of Virginia, and an M.B.A. from James Madison University. For more information, call 800 327-8262, or go to www.gecisco.com.
