The next-generation passive optical networking (NG-PON) movement took another step forward this week as the ITU-T has approved the G.989 series of standards for 40 Gbps-capable passive optical networks (NG-PON2).
ITU-T members gave first-stage approval for ITU-T G.989.2 Amendment 1, an update to the NG-PON2 physical layer specification.
This is a significant milestone for the service provider community, a number of which are evaluating how NG-PON2 can be used to provide access speeds to businesses and potentially residential customers beyond 10 Gbps.
NG-PON2 is a successor to the 1-Gigabit-capable G-PON (ITU-T G.984 series) and the 10-Gigabit-capable XG-PON1 (ITU-T G.987 series), with key enhancements provided by multi-wavelength operation and ONU wavelength tunability in both transmitters and receivers.
Based on a multi-wavelength, point-to-multipoint architecture, NG-PON2's primary solution is time and wavelength division multiplexed PON (TWDM-PON). Typically, TWDM-PON consists of four to eight wavelengths in both directions, achieving a maximum rate of up to 80 Gbps in each direction.
One of the benefits for service providers deploying NG-PON2 is that they can reuse existing optical distribution networks (ODNs) deployed for previous generations of PONs. Also, NG-PON2's wavelength plan provides for co-existence with GPON (ITU-T G.984 series) and XG-PON1 (ITU-T G.987 series).
It's still early in the game, and a number of service providers are either building foundations to take advantage of NG-PON or are conducting field trials with select customers.
At least three major service providers -- including Verizon (NYSE: VZ), Vodafone and Energia -- all conducted field trials of NG-PON in 2015.
Verizon conducted a NG-PON2 trial from a central office in Framingham, Mass., serving a FiOS customer's home three miles away and a local business. The trial, which used gear from Cisco and PT Inovação, was able to deliver broadband speeds of 10-Gbps and higher.
But large providers aren't the only ones interested in NG-PON.
EATEL, a regional independent ILEC based in Louisiana's Ascension and Livingston Parishes, installed Adtran's last-mile platform to deliver its 1 Gbps service in November 2015 while putting together a foundation to migrate to NG-PON.
Although EATEL previously deployed out a FTTH network supported by Alcatel-Lucent (NYSE: ALU) and later Calix last-mile gear, EATEL wanted a platform that would enable it migrate to NG-PON and support 10G services as demand emerged.
- see the release
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