The Ultimate OneNet Guide is here

We’ve spoken about OneNet in various different articles since its release, but what if everything you needed to know about OneNet and Ethernet networking was available in one downloadable guide?

Introducing the Ultimate Guide to OneNet and Ethernet Networking…

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Everything you need to know about the OneNet standard


“For the last 10 years, Actisense has been working on the OneNet steering committee, ensuring that the new network standard benefits both technical installers and boat users around the globe. We are committed to seeing the new standard be successfully integrated alongside the other NMEA protocols. You can be sure that Actisense has some exciting planned updates and OneNet products on our roadmap. Watch this space!”
– Phil Whitehurst, CEO of Actisense


So, we’ve all heard of OneNet, but what is it? And why is it going to be the next big thing for NMEA Networking? Chair of the NMEA 2000 Committee and Chief Engineer at Actisense, Andy Campbell spills all…

Contents of the article

  1. What is OneNet?
  2. What are the benefits of OneNet?
  3. Can you use OneNet with NMEA 0183?
  4. Is OneNet secure?
  5. What is the future for OneNet?

Don’t have time to read the article? Watch our webinar on the new networking standard.

What is OneNet?

NMEA OneNet is the third generation NMEA Standard for marine data interfacing and networking, operating on Ethernet, it has the power to bridge all three NMEA Standards together into a combined data network.  OneNet is an open industry standard, based on the power of Internet Protocol v6 (IPv6), it provides a standard method for sharing NMEA 2000 data over a Local Area Network (LAN) today and globally in the future.

“OneNet provides a common network infrastructure for marine devices and/or services on IPv6. All OneNet application protocols, such as PGN Messages, are designed to use a standard IPv6 network protocol stack. This allows OneNet to coexist with other protocols and services that operate parallel on the same network (including other marine standards such as IEC 61162-450). The standard also specifies mechanisms for connecting OneNet networks, NMEA 2000 networks, and other networks via gateway devices. Like NMEA 2000, all OneNet products will need to be certified by the manufacturer and verified by NMEA.” – NMEA


What are the benefits of OneNet?

From the very beginning, NMEA OneNet has been designed to complement and expand the capabilities of NMEA 2000, not replace it, adding its benefits to an existing NMEA 2000 network.  OneNet provides a common network infrastructure for marine devices and their services using IPv6, to allow it to co-exist with other protocols and services that operate (in parallel) on the same network.

The OneNet Standard specifies mechanisms for connecting OneNet, NMEA 2000, and NMEA 0183 networks together using gateway devices to translate between the different protocols.  Similar to NMEA 2000, all OneNet products will require the manufacturer to test them using the NMEA OneNet Certification Tool and send the results to the NMEA for verification.

As OneNet utilises Ethernet as its physical layer, it has a much larger bandwidth than NMEA 2000.  Whilst NMEA 2000 operates at 250Kbits/sec, OneNet can range from 10Mbits/sec to 10Gbits/sec, making it 40 – 40,000 times faster.  Due to this greater bandwidth, OneNet can support the high bandwidth requirements of radar, video, and sonar data streams.

Alongside the bandwidth improvement with OneNet, comes the increase in the number of physical devices that can be on the network.  NMEA 2000’s CAN Bus network has hardware of approximately 60 physical devices per network section, with an NMEA 2000 Bridge required to join network sections together.  In contrast, OneNet’s physical limit is defined by the number of ports on a network switch and that can be extended indefinitely by adding more OneNet switches.

An important power of OneNet will be to join multiple NMEA 2000 networks together using its OneNet Gateway technology.  This will allow smaller, localised NMEA 2000 networks to be created and then linked together using OneNet Gateways.  As an example, a vessel could have NMEA 2000 networks in the forecastle, engine room, and bridge with a OneNet network joining those together into a seamless data network, where distance is no longer an issue or even a consideration.

OneNet realistically has no PGN limit.  Whilst NMEA 2000 is limited to 411 standard PGNs (without the NMEA obtaining a new allocation), and 512 proprietary PGNs, OneNet does not have any meaningful PGN limit.

Something which often adds complexity to large NMEA 2000 networks is power implementation.  High power (high current draw) devices need to be powered independently, whilst low power devices can be powered directly from the backbone.  On larger installations, this can result in the network power limit being reached, requiring additional isolated power supplies to be added to the backbone.  In contrast, OneNet devices can be powered directly from the OneNet switch using PoE (Power over Ethernet), so the majority will choose that method. This approach will allow for distributed device power, up to 25.5 Watts per device, that can be simply expanded by adding additional switches or PoE modules.


Can you use OneNet with NMEA 0183?

NMEA OneNet is designed to work transparently with NMEA 2000 (as the data messages are identical) and with NMEA 0183 through a Gateway (as the data messages require conversion).  The NMEA network interconnect diagram below highlights how the various gateways will connect:  OneNet Gateway to NMEA 0183, OneNet Gateway to NMEA 2000, plus the existing NMEA 2000 to NMEA 0183 Gateway.  Gateways are great at helping reduce network upgrade costs by a significant amount, by removing the need to replace existing devices.

NMEA Introduces OneNet
Provided courtesy of the NMEA: https://www.nmea.org/Assets/nmea%20introduces%20onenet.pdf


Is OneNet secure?

Network security is a priority on any network today, especially when it comes to commercial vessels.  NMEA OneNet has made security a priority from the very beginning and uses a security model where the user creates a OneNet Secure Network and then adds OneNet Applications to that network using a process called ‘pairing’ to create a robust secure data network.

Each OneNet Application (running on a physical device) must successfully pass the NMEA Certification Tool tests in order to be issued a certificate that can be used join a secure OneNet network.  It is an important distinction to make that whilst the physical device, such as a tablet or mobile phone is not NMEA Certified, the OneNet Application running on it must be NMEA Certified for it to join a secure OneNet network and gain access to the data on it.

The OneNet network can optionally be left in an open (unsecure) state to allow use with non-certified devices if the user should require this.


What is the future for OneNet?

The NMEA OneNet Working Groups are actively working on many additions to the OneNet Standard that will be released in the coming months and years.  These include but are not limited to:

Make sure to follow our social media to stay up to date on NMEA OneNet updates and new product launches.