What about an Open Fibre to the Home (OFTTH) network?

• Chunghwa Telecom says it’s successfully completed a PoC for an open access FTTH network and the results are encouraging 
• It signed up fibre optic component suppliers and launched the PoC based on software functions running on both the general cloud infrastructure and the network equipment
• It intends to continue its active participation in open source communities and global standards organisations to further the open network

The telecoms industry has been so fixated by 5G, its disaggregation and the speedy rise of Open RAN, that the application of similar techniques to the fibre ecosystem is slipping by with very little fanfare. In fact, disaggregation could be a big win for the fibre access market as the pace of fibre build quickens, especially in the UK where full fibre access demand has seen a plethora of companies join the race to build out their FTTH networks before their rivals can get their shovels out. 

Once the networks are dug, the next race will involve signing up partners who want to use what is now presented as wholesale broadband in various flavours of Passive Optical Network (PON) fibre to reach their customers across a patchwork of different access network infrastructures. This is where the concept of the Open Access Network can offer real benefit - in fact, may be a necessity. 

Taiwanese telco Chunghwa Telecom claims that in response to what it calls the onset of ‘software-defined everything’, cloud native, and open networking, it has assembled its relevant partner suppliers in Taiwan and beyond to see how feasible it might be to build a multi-vendor fibre to-the-home (FTTH) system as an open access network. Such an approach could offer a range of familiar Open RAN-style disaggregated system advantages for the network operator and service provider (and, ultimately, the end-customer), including: innovation-enhancing vendor competition over component features, lowered OpEx and equipment costs and enhanced flexibility going forward, enabling the network owner operator and the various service and content providers to swap out and upgrade components from multiple vendors. 

Chunghwa has launched a Proof of Concept (PoC) based on software functions running on the general cloud infrastructure and the network equipment. The Taiwanese telco invited local and global suppliers to participate in the PoC as a joint effort with the goal of providing high-speed broadband access and IPTV/MOD services. 

While other big telcos in the US and Germany have already developed commercial use cases for this sort of network design, Chunghwa Telecom says it’s the first operator in Taiwan (which is a long-standing fibre hotspot) to independently carry out multi-vendor integration and successfully verify the open access network architecture.

The PoC incorporates XGS-PON OLT network equipment from Edgecore, the XGS-PON ONU network of Zyxel and Alpha, the virtualized OLT software functions of foreign suppliers Netsia, Radisys, and STL (Sterlite Technologies Limited) while Chunghwa Telecom Laboratories completed the open access network integration and also evaluated Nokia's virtualized OLT software functions which are compatible with the legacy FTTH network. 

Edgecore networks has pointed out that in a ‘non-open’ environment, OLT (optical line terminal) software must always be bundled and installed with each OLT. In the virtual (vOLT) open network, multiple OLTs can be controlled by a single server, meaning multiple and technically diverse OLTs can all be controlled centrally upon receipt of the right bit of software. This more than anything else should enable an open network environment and amongst other things, usher in zero touch automation of provisioning and connection. 

Chunghwa claims the virtual network functions constructed from software modules that support open interfaces have attracted suppliers to join the open access network market, and the supply chain is gradually taking shape. To further enhance high-speed Internet services and assist local suppliers in expanding to overseas markets, Chunghwa Telecommunications Laboratories will continue its active participation in open source communities and global standards organizations, and develop telco-cloud-related technologies with all partners.