Wireless advantages increase with IEEE 802.11n, say Rockwell Automation, Cisco

IEEE 802.11n wireless protocol has throughput up to six times existing wireless networks, better packet retry handling, and backward compatibility, according to Cisco and Rockwell Automation.  

By Mark T. Hoske December 25, 2009

IEEE 802.11n wireless protocol offers industrial automation networking applications better performance for control and automation, with throughput up to 6x existing wireless networks, better packet retry handling, plus backward compatibility.

Wireless is about eliminating cost because cabling can be unreliable. Further, IEEE 802.11n wireless protocol has additional advantages, including up to six times the throughput of existing wireless networks, explained Paul Brooks, business development manager, networks portfolio, for Rockwell Automation.

Brooks and Dan Knight, Cisco industry solutions manager, during an Automation Fair presentation in November 2009, touted the benefits of wireless, saying that wireless makes people more efficient and effective. It helps locate people and equipment more quickly, and it makes video surveillance much more economical. And IEEE 802.11n is particularly well suited for industrial monitoring and control, especially in applications where cabling is impractical or might fail. Often, a combination of wired and wireless technologies can quickly provide the best possible implementation, Brooks said. In one of many examples provided, Knight explained how Metroline Greenhouses, with 5.8 million square ft, reduced inventory by 15%, improvement worker productivity, with same staffing.

Rockwell Automation has been working with Cisco on industrial Ethernet network, most recently using the Cisco unified wireless network. Brooks and Knight said the unified wireless network is architecturally flexible, can stand alone in an application, or can operate with a controller-based solution, with components, as needed, for the application.

IEEE 802.11n protocol has:
– Multiple input and multiple output (MIMO) capabilities, which increases fidelity.
– 40 MHz, packet aggregation (like carpooling), and multiple antennae capability, which can multiply throughput (more lanes on the highway);
– Fewer transmissions and acknowledgments, which helps with many control applications;
– Backward compatibility with IEEE 802.11a, b, and g in 2.4 and 5 GHz, for less interference and more channel operations; and
– Twice the reliability and predictability.
Enhanced testing, Brooks said, has demonstrated:
– Point to multi-point capability providing wire-speed performance through a wireless network;
– Packet aggregation of up to 19,000 packets per second;
– Zonal coverage to find non-overlapping channel. This is made possible with 21 channels using 5 GHz, compared to 3 channels in 2.4 GHz.
– Up to 300,000 packets/sec of data are possible using multiple radios and channels; and
– Radio frequency co-existence is possible, IEEE 802.11 b/g and n with IEEE 802.15.4. Four channels are available and the network will locate others as available in real time.

"For the right applications, this is very suitable technology," Brooks said.

Also read, from MBT :

– Wireless technology enables chemical plant’s Project Zero ;

– Wireless demonstration project operates ISA 100.11a for process automation ; and

– Motorola enterprise mobility: Wireless LAN, industrial sensing growth expected .

IEEE 802.11n has benefits beyond speed

IEEE 802.11n is about much more than speed, according to a Rockwell Automation and Cisco presentation at Automation Fair. Rockwell Automation provides a PDF of the presentation here www.rockwellautomation.com/events/automationfair/get/presentations/AF2009Tech42.pdf.


– Mark T. Hoske, online products editor, Manufacturing Business Technology , MBT, www.mbtmag.com


Author Bio: Mark Hoske has been Control Engineering editor/content manager since 1994 and in a leadership role since 1999, covering all major areas: control systems, networking and information systems, control equipment and energy, and system integration, everything that comprises or facilitates the control loop. He has been writing about technology since 1987, writing professionally since 1982, and has a Bachelor of Science in Journalism degree from UW-Madison.