Optical access vendor Adtran announced the development of what it calls Subscriber Edge Tunable (SET) transceivers for next-generation passive optical networks at its annual analyst event held this week in its Huntsville, Alabama headquarters.
Adtran says its entry into this ‘new category of tunable optics’ addresses several key technology and innovation gaps that have hindered market development for multi-wavelength access networks. The new tunable 10G optics could save network providers up to 80 per cent in capital and operational costs as they look to upgrade their access infrastructure, according to Adtran.
The NG-PON2 architecture, as described by ITU-T standards, can employ ‘stacked’ passive optical networks on up to eight wavelengths. The multi-wavelength capability will help operators pull more capacity out of their existing fibre access plants. Adding new wavelengths also provides a simple upgrade path when the existing PON capacity has become exhausted.
The high cost of NG-PON2 optics has been cited as a potential barrier to adoption of the new technology, however. Adtran – and others – have already developed lower-cost, fixed-wavelength options for the optics (see Adtran touts flexible optics for better NG-PON2 economics).
The subscriber end of the link is even more cost sensitive, but would really benefit from wavelength agility. A key technology for the home or office will be a low-cost tunable transceiver that allows the end-user equipment to select and tune to the wavelength that’s been assigned to that customer.
Fast switching times are also a necessity if operators are to exploit software-defined network (SDN) management, which will allow them to ensure the highest quality of experience in a user-defined service structure, for example by automatically offloading traffic from congested or out of service wavelengths or ports to alternative wavelengths on less utilised network assets.
Seeing that such technology wasn’t available commercially, Adtran Labs rose to the challenge. ‘Adtran identified there was a void in the 10G optics market a few years ago that would hold back the adoption of mass market 10G PON applications like residential and business gigabit broadband,’ explained Kurt Raaflaub, head of strategic solutions marketing at Adtran.
‘Current optics vendors are often unwilling to enter a new market until sufficient sales volume forecasts support their development costs. This sets up a chicken and egg scenario. Adtran recognised that to accelerate the adoption of scalable NG-PON2 technologies … the lack of operationally effective 10G optics would need to be addressed.’
Adtran said it managed to achieve the low cost point required by using only mature, commercially viable building blocks to create the overall solution. ‘Alternative exotic implementations on the market have led to much higher cost points which we have avoided,’ said Raaflaub.
The new laser will tune to a new wavelength in less than 50ms, but Adtran is coy about other details. But the technology could give the company the edge in the competition to be selected by Verizon for its NG-PON2 deployment (see Verizon evaluates suppliers ahead of NG-PON2 deployment).
Adtran expects the initial versions of these new optics to be available in 2017 to align with the expected first commercial NG-PON2 networks being deployed. SET optics will be one of several technology choices in the company’s NG-PON2 portfolio, which will include both fixed-wavelength and tunable transceivers.
Commenting on the announcement Julie Kunstler, principal analyst at Ovum, said that Adtran’s subscriber edge tunable optics solution will support the cost-efficient expansion and unbundling of the FTTx architecture and accelerate the roll-out of 10G services for business and residential customers through ‘disruptive pricing’ of the customer premises equipment.
