Experts agree that Single Pair Ethernet (SPE) is becoming a key technology in the Internet of Things (IoT) and Industrial Internet of Things (IIoT). However, no one is yet been able to say exactly how and where SPE will be used. Due to a range of different interests, the committees are avoiding addressing open questions.
“Single Pair Ethernet is a network technology with revolutionary potential and is currently being worked on. Several committees are working at high pressure on the standards. But there is still a significant need for clarification until SPE can expand in building automation and in the LAN,” said Shajan George, Technical Director at R&M India
For example, to date, the standardization committees have not dealt sufficiently with the influence of remote power supply (Power over Data Line, PoDL) or the implementation of multi-drop capability. To save time, they are focusing almost exclusively on point-to-point connections without a remote power supply. And that results in the following situation: The standards for the SPE cabling link are today at the same level as those for existing cabling (Cat. 5, 6, 6A or 8.1). But that does not mean that SPE should replace the tried and tested RJ45 interface. The possible uses still have to be fully discussed.
SPE as an extension of the digital ceiling
One specific operational area is building automation. R&M is convinced that SPE is perfect for connecting a large number of applications in building automation to the data network. SPE components are much smaller than RJ45 adapters. Therefore the connection density on network devices can be increased. The connectors on sensors and actuators can be downsized. The cabling will become comparatively inexpensive. However, SPE does not support the bandwidths which classic structured cabling with the tried and tested RJ45 interfaces enable. Applications such as WiFi6 and 5G DAS require bandwidths over 10 Gbit/s. Currently SPE can only provide 10 Mbit/s on the required distances of up to 100 m. This means that initially SPE is not suitable as cabling for an application-neutral infrastructure in a building or on a campus.
Things will become interesting, however, within the digital ceiling zones, between the service outlet (SO) and small IoT applications. From the point of view of R&M, there are diverse and new possibilities here for SPE. The ISO/IEC 11801-6 standard already makes it possible to use application-specific cabling after the service outlet. This has thus laid the foundation stone for a solution for the network connection of light, temperature, smoke and air sensors or controls for windows and blinds.
The SPE solutions build on R&M’s long-term experience in structured cabling do not require any additional cabling and just minimal investment to integrate Single Pair Ethernet in a digital ceiling infrastructure. This once more confirms the advantages of the digital ceiling concept. It offers investment and future security. This is how Single Pair Ethernet can be realized cost effectively at short notice.
