Two Approaches to Faster PONs

The next steps in passive optical networking are upon us. The precise way forward, however, is still not clear as two standards groups are suggesting different approaches.

The names sound similar. The ITU Telecommunication Standardization Sector (ITU-T) is working on Next Generation Passive Optical Network (NG-PON2), while The Institute of Electrical and Electronics Engineers’ (IEEE) 802.3 Working Group is creating the Next Generation Ethernet Passive Optical Network (NG-EPON) standard.

NG-PON2 clearly is more evolved. Verizon, according to Light Reading and other sites, has successfully tested it and is acting on that success. Mari Silbey reports that the carrier ran the trial from its central office in Framingham, Massachusetts, to a home three miles away that is served by FiOS.

The details of the test, which was performed in conjunction with Cisco and PT Inovação, are in the story. The bottom line is that NG-PON2 makes possible 10 Gigabit per second (Gbps) symmetrical service with the potential for higher speeds. The company will issue a request for proposals (RFP) leading to “a major network upgrade initiative.”

The use case is persuasive, according to Silbey:

The primary appeal of NG-PON2 is its application in commercial services. Telecom providers face growing competition in the business services arena, and increased demand for more bandwidth from customers, particularly related to mobile fronthaul and backhaul applications.

Curtis Knittle, CableLabs’ director of Optical Technologies, wrote that NG-PON2 takes a time and wavelength division (TWDM) approach and stacks four wavelengths on a fiber. Each offers 10 Gbps, though individual optical network units (ONUs) have a 10 Gbps capacity.

NG-EPON clearly is less evolved. Knittle says that key questions – including the number of wavelengths involved, the bit rate per wavelength, whether transceivers will be tunable, and the status of channel bonding – remain unanswered.

NG-EPON proponents better hurry up. First to market advantages are important, even in high technology. This spring, ADTRAN said that it is adding NG-PON2 capabilities to its flagship Total Access 5000 platform, according to Lightwave Online. In late June, Calix introduced cards for its E-Series platforms that add NG-PON2 in both fixed and tunable wavelengths, according to the press release. The new cards also add 10 Gbps capacity to the platforms.

Carl Weinschenk covers telecom for IT Business Edge. He writes about wireless technology, disaster recovery/business continuity, cellular services, the Internet of Things, machine-to-machine communications and other emerging technologies and platforms. He also covers net neutrality and related regulatory issues. Weinschenk has written about the phone companies, cable operators and related companies for decades and is senior editor of Broadband Technology Report. He can be reached at cweinsch@optonline.net and via twitter at @DailyMusicBrk.