The proliferation of smartphones and availability of 3G and 4G networks have led to a significant rise in the adoption of data services. However, service providers are struggling to support the high data traffic on their networks. To meet the rising bandwidth requirements of users, they are now resorting to the deployment of optic fibre cables (OFC) in their networks. However, replacing the existing copper cable network with OFC is not only a complex task, but also entails significant investments. Moreover, the investments made over the years in these copper cable networks will yield poor returns if they are replaced with fibre cables.

Meanwhile, low return on investments from fibre deployment has compelled some operators to limit their OFC network roll-outs. However, in a market where the first-mover advantage yields significant benefits, delaying the roll-out of fibre cable can adversely affect a company’s position.

In order to reduce the time-to-market for high speed broadband connectivity and use the existing copper infrastructure, service providers are opting for fibre-to-the-building (FTTB) and fibre-to-the-cabinet (FTTC) deployments instead of fibre-to-the-home (FTTH) installations. For offering last mile connectivity to customer premises through the existing copper networks, operators deploy technologies such as VDSL2. This arrangement was not possible earlier due to the bandwidth constraint of copper cables. However, technology advancement has led to the introduction of VDSL2, which enables downstream access speeds of up to 100 Mbps as it operates on higher frequency bands - 17 MHz and 30 MHz. Further, with the implementation of vectoring technology, noise generated in the cable network due to crosstalk, which in turn reduces the downstream access speeds, has also been corrected. The combination of two technologies has enhanced the value of copper cables and has regenerated interest among service providers. Using these technologies, a downstream access speed of 80-100 Mbps for short loop (500 metres) has been achieved. However, at longer cable lengths, the downstream speed tends to reduce to as low as 10-20 Mbps.

Besides speed enhancement, the deployment of VDSL2 and vectoring technology entails lower capex costs as compared to OFC implementation. According to Alcatel-Lucent, the deployment of vectoring with FTTN is three times cheaper than FTTH deployment, while JP Morgan estimates the difference to be four times. In addition, the installation of vectored lines is easier than the deployment of fibre.

Several telecom operators are already undertaking FTTB and FTTC deployments and conducting trials using VDSL2 and vectoring technology. For instance, Netherlands-based operator KPN has introduced the vectoring technology at 29 of its existing VDSL outer rings as part of a pilot project, and has achieved a downstream speed of 80 Mbps. The company is currently extending the technology to other VDSL outer rings. Similarly, Belgian operator Belgacom is deploying the VDSL2 and vectoring technology across its nationwide network, which is expected to increase the downstream speed from 30 Mbps to 70 Mbps. The deployment is scheduled for completion in 2016. Another European operator that is undertaking VDSL2 and vectoring technology deployments is Deutsche Telekom. The technology will enable the operator to offer a speed of up to 100 Mbps by end-2014, a marked improvement over the current 16 Mbps speed provided to its broadband users.

Another technology that is gaining prominence for its faster downstream speeds is G.fast. Currently at the testing stage, G.fast is considered to be a technology that can enable copper to compete with fibre in the near term. The technology can provide a speed of 1 Gbps through copper networks up to 100 metres, as it operates on a wider frequency band of 106 MHz as compared to VDSL2 which operates on the 17 MHz/30 MHz band. However, like VDSL2, G.fast exhibits a rapid decline in downstream speeds with an increase in the length of the loop. In fact, the impact of crosstalk on G.fast technology is more severe than that on VDSL2 as the former operates on a higher frequency band. Further, without the deployment of vectoring technology, the speed may reduce to 20 Mbps.

As witnessed in the case of VDSL2 and vectoring technology, G.fast technology has garnered significant interest from European operators. In fact, the first trial of the technology was conducted by Telekom Austria in partnership with Alcatel-Lucent. The trials yielded a speed of 1.1 Gbps for a cable length of 70 metres and 800 Mbps for 100 metres. The vendors are also making efforts to improve G.fast technology in order to deliver speeds of about 1 Gbps over a distance of over 250 metres.

With rapid advancements in such broadband technologies, copper-based networks have once again gained prominence and become an integral part of operators’ business plans as they continue to focus on fibre networks. In this regard, copper will act as the middle path in the transition to fully fibrised networks.