Hardened Ethernet Brings Throughput, Flexibility to Transportation Applications
January 7, 2016 by John Day
From Cars to Signage, Ethernet Use is Growing; Park Assist Uses Hardened Ethernet for Advanced Parking Facility Sensor System
By Tony Lefebvre
The use of Ethernet – the most popular networking technology in corporations and data centers – is growing in automotive and transportation applications. With use cases that include in-vehicle connectivity, traffic control signaling, vehicle detection, video surveillance networking and parking lot automation, Ethernet’s throughput, scalability, reliability, and cost advantages contribute to this growing use of technology.
The critical common attribute for all of these applications is that the Ethernet equipment must be designed specifically for use in harsh environments including where wide temperature ranges, areas with shock, vibration, dust or water can be expected. This means that Ethernet equipment that is used in environmentally controlled office environments is not appropriate for these applications, but rather hardened Ethernet systems are necessary.
What is Hardened Ethernet?
Hardened Ethernet equipment offers the same support of TCP/IP, 10/100/1000 Mbps data rates and layer two and three data forwarding as corporate Ethernet systems. But it includes industrially hardened components and enclosures as well as support for some standards and features that allow it to be used in any transportation application, but also in factory floor, power substation, outdoor enclosures and other harsh environments. Some of these include:
• Wide temperature range: Hardened Ethernet systems are designed for outdoor applications and should operate error-free in a temperature range from -40°C to 75°C, making them suitable for outdoor equipment cabinets, factories and utility substations.
• Hardened casing: Outdoor and factory floor locations need hardened Ethernet switches that are protected from dust, dirt, water, and also incidental jostling. This requires an industrial-grade metal enclosure to ensure reliable operation in harsh environments.
• IEEE 1588 Precision Time Protocol (PTP): Many control applications require real time data throughput that is clocked at each stop in the data path. PTP synchronizes the clocks throughout a computer network to deliver timing accuracy in the sub-microsecond range.
• Redundant network and power inputs: Network uptime is critical for transportation applications. With redundant power and network inputs, hardened Ethernet products improve their reliability by guarding against a component failure taking down the entire network.
• UL Class 1 / Div 2 Rating: As hardened Ethernet products may be used in locations where flammable gases or liquids are present, they need to be certified to not explode or ignite. This UL certification indicates that these systems are hermetically sealed and designed to be non-sparking and not incendiary.
• IEC 61850-3: This standard is designed to provide interoperability for substation automation for electric power substations. There are a number of specifications that are part of this standard (manufacturing message specification, generic object oriented substation event, and others), which run on TCP/IP networking protocol. Most of these specifications do not impact the Ethernet switch or network infrastructure, but the switch must offer the right performance levels (less than four-millisecond round-time communications) to support these specifications.
• IEEE 1613: In many applications, electromagnetic interference (EMI) can disrupt communications. IEEE 1613 class 1 rated devices are protected from EMI, but can still experience some data loss or errors from extreme EMI. Class 2-certified products provide error-free operation when stressed by EMI. This requirement is most significant in applications involving electric power substations.
• Power over Ethernet: The PoE standard enables devices on the network to be powered via the copper Ethernet cable that is used for data transfer. For fiber networks, switches that comply with the IEEE 802.3at 2009 and IEEE802.3af 2003 standards can combine data received over a fiber optic link with -50VDC power delivered to powered devices (PD) using a separate unshielded twisted pair cable connection.
• SFP: Small form factor pluggable optics provide flexibility to outfit a switch with the fiber-optic network interface that supports the connector type, data throughput and fiber cable (single mode or multimode) requirements for that link. SFPs can now be used in hardened Ethernet applications in a way that maintains the integrity of the hardened casing.
Park Assist Uses Hardened Ethernet to Simplify Parking
Park Assist entered the parking technology field in 2005, and in 2010 pioneered the first camera-based parking sensor system in the industry. Over the past decade, the company has become the industry’s technology leader with successful installations spanning 20 countries.
Park Assist’s technology platform includes autonomous microcontroller-powered sensors that transmit parking data and streaming video to a core system server. On that server is Park Assist’s proprietary software, which provides advanced detection and analysis to enhance operations.
Smart-sensors within the parking structure provide intelligence at the parking-space level. In a standard Park Assist installation, smart-sensor cameras are used to identify vehicles and monitor occupancy in every parking space, which enables the system to show drivers where empty spots are available. At kiosks located strategically within the parking structure, Park Assist’s license plate recognition (LPR) system can track vehicles to help people find out where they parked.
In addition, Park Assist APIs and mobile apps can be used to make customer-facing features accessible across a wide range of smartphones and tablets.
Hardened Ethernet is a critical element of the system, providing bandwidth and connectivity for Park Assist core servers and other equipment. The company has implemented its system in garages across the country, which are subject to a wide variety of weather conditions and are both indoor and outdoor, making wide temperature range and hardened system casing essential. Other key features include support for SFP ports so that fiber-optic cable can be used for long cable runs to servers. Remote management of the network via a web interface is also an important feature.
Ethernet may be the only technology that has been on the market for decades and is still growing into new applications – most other technologies have been made obsolete over that time period. Hardening Ethernet systems – switches, network controllers, media converters and other systems – is a great example of the way Ethernet is evolving into new markets.
For transportation applications, like Park Assist’s parking systems, the wide temperature range, hardened components and case make Ethernet a logical and easy choice for expanding the connectivity in autos, road signage and parking systems.