One-pair pair cable could be the ‘new’ four-pair cable, if authorities start to acknowledge the amazing opportunities of widespread connectivity. Murray Teale reports.

A cable option invented in 1881 by Alexander Graham Bell is making its presence felt again.

The one-pair cable and connector is back, along with the Internet of Things (IoT), smart cities, distributed building services and the associated digital disruption of the way we operate.

This ‘new’ option may soon take the lead in the amount of cable installed in Australia – or it could be banished and return where it came from.

Background

For one-pair cabling to be successful it would need to address a specific need and have distinctive advantages over existing methods. So the question is: what are the benefits?

The primary consideration for one-pair cabling is IoT applications. The concept is to embed electronics into devices, sensors and actuators, enabling them to communicate with the internet thereby linking an estimated 30 billion devices worldwide by 2020.

With surgically inserted devices connecting people to the internet for medical monitoring, we may have to add a few billion more.

This degree of communication is exciting governments and businesses worldwide as they clamber to take advantage of the new paradigm.

The devices have two typical requirements: power for the electronics and internet capability. The power can be delivered by various sources including copper cabling, batteries, energy harvesting from the environment and other methods. The choice will match the specific application.

Conductivity can be established by use of copper cabling, optical fibre cabling, wireless, Bluetooth, powerline communication, G4/G5 GSM or various other methods including free light in air.

Each method for powering and connecting to the internet has its advantages and limitations, such as safety issues, security, operational reliability and cost.

An example of how IoT operates would be a modern pacemaker.

The device would be connected to the heart and powered by batteries that last more than 10 years. Each night the pacemaker would transmit data for the previous 24 hours to a device next to the bed by, say,  Bluetooth. That device would then transmit via 4G to a location overseas that collected and monitored the data.

In an IoT world the passing of a pre-set threshold in the data stored overseas might mean that an ambulance was called, the front door unlocked, security turned off, cameras turned on, a hospital room booked, medical records sent and health workers notified.

One-pair twisted pair cabling will be capable of delivering power and communication. A device connected to a one-pair copper cable has the advantage of constant power and a permanent communication pathway.

However, each methodology has ways of dealing with limitations, so the most likely scenario is that a combination of solutions will be used to meet specific applications.

The current four-pair generic cabling application has a typical reach of 90m for installed cabling and 100m for a channel (90m of cable and 10m for patch cable). It is capable of delivering 100W of power.

Optical fibre cabling offers greater bandwidth (data flow rate) over longer distances. It has a high level of security but does not deliver power to the end device.

Wireless offers easy deployment of multiple devices in a location but does not deliver power.

Bluetooth offers good connection of personal devices but has minimal reach.

Powerline communication delivers communication and power to a location but is dependent on having electrical power cable installed.

G4/G5 GSM offers great (worldwide) reach and easy deployment. However, it is highly dependent on the carriage network to operate and typically attracts ongoing carriage service charges.

The current deployment model is effectively servicing existing applications using established infrastructure options.

Why one pair?

One-pair twisted pair cabling is not intended to directly replace any existing delivery option.

It is aimed at taking a slice of the projected 30 billion connected devices in 2020 – up from 8.4 billion in 2017.

That projected growth of about 21 billion devices over three years must be seen as an opportunity

Although one pair is being developed in support of industrial application up to 15m link lengths, the real target market is in connecting IoT devices.

What are the targets?

• connectorised one-pair links;
• 1,000m reach;
• power delivery for distributed building automation applications and process control (IoT devices); and
• 10Mbps data rate.

What are the benefits?

• lower cost;
• longer reach than four-pair twisted pair (sacrifice speed for reach);
• power and communication on the same cable;
• low-cost interface (the cheaper the connection the more you sell and the greater the advantage competing against other delivery methods); and
• good security potential compared with wireless technologies.

An increase in connected devices will support the electro-technology industry and generally support the emerging innovative technologies that will change the way organisations operate.

Innovation in this space will bring highly profitable businesses offering products and services we have not yet imagined.

Where we’re at

The international customer cabling group JTC1/SC25/WG3 was asked via liaison from the IEEE 802.3 working group for recommendations defining an optional medium-dependent interface (MDI) for single-pair cabling (February 2018).

At that meeting four presentations were made in support of three new one-pair connectors for inclusion in the ISO/IEC 11801 series (called AS/NZS 3080 in Australia when this article was written).

With each option two variations were included – for industrial applications and for non-industrial.

The IEEE P802.3cg 10Mbps Single Twisted Pair Ethernet Task Force approved revision of their project objectives in March 2018.

In May 2018 at the joint AS/NZS Standards meeting it is planned to have presentations on the one-pair connectors to inform members before voting internationally.

A decision on which connectors will be adopted is expected by late September.

The work on the incorporation of one-pair cabling in the ISO/IEC 11801 series will continue at the IEEE802.3 meeting in Washington on 24 September 2018.

Implementation issues

The mandatory cabling Standards AS/CA S008 and AS/CA S009 are under review, and working drafts indicate there is no mandatory roadblock to the introduction of one-pair systems.

The international Standards are driving IoT across multiple sectors, including the international customer cabling Standard on which our performance Standards are based.

Recent industry submissions to the Australian Building Codes Board (ABCB) to include pathways and spaces for telecommunication cabling in the National Construction Code (NCC) have been rejected.

This seems to be based on insufficient evidence of an adequate cost/benefit figure.

It also seems to support the notion that it’s more cost effective to establish a pathway in a building after it has been constructed.

The last failed submission to the ABCB seemed only to be attempting to establish a pathway for carriage service to the premises. Given that, it seems there will be no pathways and spaces allowed in the NCC for physical connection of IoT devices any time soon.

It is unlikely that industry will engage in the process any more or make further submission to the ABCB until government acknowledges the issue of insufficient pathways and spaces in buildings. Government must also acknowledge what the limitations are costing Australia financially, the effect on social and community development, and the delayed or missed IoT opportunities.