Using the right protocol
Open integration of fieldbus solutions in Ethernet is moving ahead rapidly. These days it is hard to find a protocol which has not been tunnelled via Ethernet, or where IP has not been used as a key selling point. It seems that the application of Ethernet as a control network is a hot topic, both today and for the future.
However, in the general Ethernet / IP euphoria, it is often forgotten that not all Ethernet solutions are compatible. By tunnelling, old protocols are merely repackaged. Limited protocols will remain limited, even over IP.
Picture yourself driving a stone-age vehicle along the highway fuelled by IP integration - the outcome remains locked in the proprietary format, so the customer’s eventual disappointment is just as predictable as it is inevitable. The struggle for the correct protocol through Ethernet has just begun and is almost at the same stage as the fieldbus was 6 to 8 years ago.
In this respect, LONWORKS® is ahead of its time with its standardised application layer and optimal compatibility in the IP world. Yet the LONWORKS community still remains open to collaboration: LonUsers®, for instance, are helping to promote the integration of BACnet and KNX in the European TC-247-Standard. The driving force is the need to provide the end user with an open solution.
Important factors: Openness and Interoperability on IP
Today, IP and Ethernet have much more to offer than simple tunnelling solutions. You can also reap the strategic benefits of open systems by using the correct protocol. This openness leads to a synergistic effect, resulting in a myriad of interoperable products being manufactured.
Personal computers and the Internet have already proven that open innovations are the way forward to bring advanced technology to the mass market at the right price. Yet, while clear standards for the Internet and Intranet web portals have been established, infrastructure networks remain largely undefined. More and more, Profi-Bus, LONWORKS and BACnet are believed to become market leaders. With this article, LONWORKS would like to present its technology and its ability to integrate itself into such open systems with Ethernet.
Present status of LONWORKS in the Ethernet age
The LONMARK standard and LONWORKS technology together offer one of the strongest application layer standards for interoperable networks. Its object-oriented structure with customised node interfaces for various applications is still unique. LONWORKS Peer-to-Peer solutions combined with today’s event-oriented communication offers higher flexibility and stronger performance in control networks, in comparison to systems using Client-Server Architecture.
LONWORKS has been an ANSI/EIA/CEA-Standard for several years and is therefore truly open. Based on an initiative launched by various European LonUser Organisations, this standard will be implemented along with the CEN/TC 247 - standard (known as ‘Keymark’) into the European norms.
Thus, the following parts will be classified under ENV13154-2 Control Network Protocol (CNP) as an EN Standard:
Part 1: LonTalk® Protocol Stack Specification (ANSI/EIA/CEA 709.1 b)
Part 2: Two-wire communication in free topology (ANSI/EIA/CEA 709.3)
Part 3: Power-Line Channel for communication over 230 V (ANSI/EIA/CEA 709.2)
Part 4: IP-Tunnelling (ANSI/EIA/CEA 852)
Part 5: Compatibility examination
Part 6: Certification
Inventors and holders of patents
in the field of technology (e.g. Xerox in Ethernet’s case) have
to assure the authorities that patents or exorbitant fees will not hinder
the standardised technology. Should no
assurance be given, the standard will not be admitted. Echelon Corporation
officially submitted these assurances to the CEN in the summer of 2003.
So far, the first voting of the multi-level political voting process has
taken place and was unanimously accepted. Within the next two years, the
CEN-Norm will be converted into an EN-Norm and will thus automatically
become an ISO-Standard. Based on this, innovation protection now guarantees
the long-term protection of the technology.
The LONMARK organisation will play an important part in terms of the compatibility tests and certification (part 5 and 6). These important tasks should be perceived as part of the service by local LONMARK affiliates. To this end, the European LonUser organisations along with LONMARK and Echelon are talking about establishing a uniform organisation controlled by its users.
What does Keymark mean for the planner / technician?
The Keymark norm will lead to an open standard that remains in force for a long period of time. This will protect investments made in buildings and guarantee the long-term maintainability and upgradeability of the installation. So Keymark is more than just a standard; it is a building technology quality mark, giving the designer or specifier the assurance of knowing that they selected products tested for their compatibility.
Interoperability: From Free Topology to the Internet
While the international standardisation front experienced a major breakthrough, manufacturers and technology providers are carrying innovation to a level not seen since the introduction of LONWORKS technology. Echelon, Loytec, and Infranet Partners are three companies that already offer products based on the new IP-852-Standard.
A system integrator will therefore be able to continue working as before: the only difference is that he now has the possibility to seamlessly integrate Ethernet channels into his system solutions. Graphic 1 depicts this solution from the system integrator’s view with the products referred to above. The application of libraries, methods and experiences can still be applied without any interruption.
Yet Ethernet is not the only area in which the world-renowned LONWORKS community has developed innovative solutions. After launching the integrated Smart Transceivers FT3120 and FT3150 for the FT-10-Channel, Echelon also designed a new Power line Transceiver PL3120 and PL3150. This new transceiver combines both the Neuron chip and the time consuming Transceiver logic on a single chip, requiring only one third of the current processing costs. Power line nodes for the 230V power network can now reach beyond limits that, were unthinkable until now, due to their high unit prices. This will surely rekindle interest in home automation power line solutions based on LONWORKS.
In addition, Cypress introduced two new Neuron-chips equipped with additional periphery functions and energy saving 3.3 V - technology.
LONMARK: an open global innovation
On the one hand, local operating networks can be integrated into webportal applications by means of standardised interfaces (SOAP). LONWORKS then becomes the first choice for large networks reaching into single households (for example energy management).
Enel’s project to connect electricity meters to IP and Power lines in Italy is only one of many. However, what is impressive about Enel is its network size: 27 million appliances, of which more than a third have already been installed. This is of special interest in all areas where real-time data is needed in web portals.
On the other hand, the IP-852 standard will allow LONWORKS networks to expand through IP interoperability. This way, Ethernet nodes can be certified as LONMARK devices and, using the existing tools, be connected interoperably to other devices on a physical layer (Power line, free topology, radio etc). This path is often chosen in the field of building automation.
Global integration into the essential norms is perhaps one of the most important advantages for the end user. In addition to ANSI/EIA/CEA, EN and ISO, the Chinese administration also accepted these norms as their national standard. Thus, open innovation will continue on an independently guaranteed long-term basis. The same field devices can be used in both the cases mentioned above.
Real Interoperability and open innovation are not just marketing points for LONWORKS: numerous manufacturers, system integrators and users throughout the world are applying them. Thanks to the high quality of the LONMARK Application Layer, American, European, and Asian devices can be made into one functioning system.
This gives the planner and system integrator a wider range of compatible products and medium-term fixed costs. This means that a long-term price advantage will join the many other advantages which flow from adopting the LONMARK standard: good news for planners and building owners who want to realise the benefits of open systems.