IEEE 802.3cg™ “Standard for Ethernet Amendment: Physical Layer Specifications and Management Parameters for 10 Mb/s Operation over Single Balanced Twisted-pair Cabling and Associated Power Delivery” is currently under development by the IEEE P802.3cg 10 Mb/s Single Twisted Pair Ethernet Task Force and anticipated to publish in June, 2019. A cost-effective, low speed Ethernet application offers many benefits in support of not only industrial and automotive networks, but also intelligent building networks linking automation, HVAC, security/access, lighting, IoT, and other control and actuator based devices and systems. Single balanced pair cables can be used in place of a wide range of fieldbus cables, including RS-485 twisted-pair, RG-6 coaxial, and instrumentation cables and single-pair Ethernet can enable interoperability when used in place of RS-232, RS-485, CAN, HART®, and other proprietary and custom communication protocols. This amendment will define two Physical Layer (PHY) specifications and management parameters for 10 Mb/s operation over backplanes and single balanced pair cabling. These solutions will support optional Energy Efficient Ethernet (EEE).
The new PHY specifications under development are as follows:
10BASE-T1L: 10 Mb/s transmission over single balanced twisted-pair cabling up to at least 1 000 m reach
10BASE-T1S: 10 Mb/s transmission over short reach single balanced twisted-pair cabling
In addition, 10BASE-T1L will support optional Type E Power over Data Lines (PoDL) remote power provisioning. Four classes of Type E power sourcing equipment (PSE) will be specified to support up to a minimum of 13.6W over up to 1 000m of single balanced pair point-to-point cabling.
The current focus of the IEEE P802.3cg 10 Mb/s Single Twisted Pair Ethernet Task Force is the development of a draft for Task Force review.
The 10 Mb/s Single Twisted Pair Ethernet Call-For-Interest Consensus Presentation can be found here: http://www.ieee802.org/3/cfi/0716_1/CFI_01_0716.pdf
The Project Authorization Request (PAR), approved on December 7, 2016, can be found here: http://www.ieee802.org/3/cg/IEEE_P802_3cg_PAR_071216.pdf
The project objectives, approved on November 10, 2016 (refer to: http://www.ieee802.org/3/cg/objectives_10SPE_111016.pdf) are as follows:
- Preserve the IEEE 802.3/Ethernet frame format at the MAC client service interface
- Preserve minimum and maximum frame size of the current IEEE 802.3 standard
- Support a speed of 10 Mb/s at the MAC/PLS service interface
- Do not preclude meeting FCC and CISPR EMC requirements
- Support for optional single-pair Auto-Negotiation
- Support optional Energy Efficient Ethernet
- Support 10 Mb/s operation in automotive environments (e.g. EMC, temperature) over single balanced twisted-pair cabling
- Support 10 Mb/s operation in industrial environments (e.g. EMC, temperature) over single balanced twisted-pair cabling
- Do not preclude the ability to survive automotive and industrial fault conditions (e.g. shorts, over voltage, EMC, ISO 16750)
- Do not preclude working within an Intrinsically Safe device and system as defined in ISO 60079
- Define the performance characteristics of a link segment and a PHY to support operation over this link segment with single twisted pair supporting up to four inline connectors using balanced cabling for up to at least 15 m reach
- Define the performance characteristics of a link segment and a PHY to support point-to-point operation over this link segment with single twisted pair supporting up to 10 inline connectors using balanced cabling for up to at least 1 km reach
- Support fast-startup operation using predetermined configurations which enables the time from power_on**=FALSE to a state capable of transmitting and receiving valid data to be less than 100ms
- Maintain a bit error ratio (BER) at the MAC/PLS service interface of less than or equal to 10‑10 on link segments up to at least 15 m, and 10‑9 on link segments up to at least 1 km
- Specify one or more optional power distribution techniques for use over the 10 Mb/s single balanced twisted-pair link segments, in conjunction with 10 Mb/s single balanced twisted-pair PHYs, in the automotive and industrial environments