HUNTSVILLE, Ala.—Verizon is sticking to its guns that NG-PON2 is the next long-term bet for its fiber-to-the-premises (FTTP) network, bypassing the interim steps of migrating first to 10G-PON and XGS-PON systems.
Vincent O’Byrne, Ph.D., director of technology at Verizon, told attendees at this week’s Adtran Connect event that NG-PON2 will provide the telco with a more future-proofed network path.
“We want technology that can grow without driving a lot of outside plant changes by concentrating our efforts on the reuse of spectrum versus the use of physical plant,” O’Byrne said. “The move from BPON to GPON was a fairly large investment and the move to go from GPON to another new technology requires a large upfront investment in OLTs.”
Unlike fellow service providers, CenturyLink and AT&T have set a path to conduct a hybrid migration by using 10G-PON and XGS-PON systems; Verizon plans to migrate directly to NG-PON2.
The service provider said that the NG-PON2 path allows it to offer more services on one fiber and thus control deployment costs as it looks to stay on pace with the competition.
“As we look for a cost effective solution that can support multiple residential and business services on the same fiber, we have several options,” O’Byrne said.
While XGS-PON and 10G-PON were considered, O’Byrne added that these approaches had their own limitations, particularly when delivering business services.
“The 10G options you have with XGS-PON and 10G-PON support only a single wavelength versus multiple wavelengths,” O’Byrne said. “From a long-term perspective, a single wavelength is something that is a short-term solution for business services.”
Common business, residential architecture
By adopting NG-PON2, Verizon wants to have a common architecture that can simultaneously support business and consumer customers on various optical wavelengths via a single fiber.
Because XGS-PON and 10G-PON standards are designed to only support a single wavelength, Verizon is concerned that it would not be able to parse out residential and business traffic.
“Carrying residential and business traffic on the same fiber is hard to do from our perspective with a single wavelength,” O’Byrne said. "Our business customers get very nervous when our techs are doing something on the residential customers and its effect on SLAs.”
Besides being able to support multiple wavelengths to parse business and residential customer traffic, NG-PON2 can also scale to meet other higher speeds of 40 Gbps and above.
“In the case of NG-PON2, you’re able to handle it by having businesses on the same wavelength and residential on another so if something occurs on one wavelength you can isolate and resolve problems,” O’Byrne said. “It also has the ability to support higher speeds beyond 10 Gbps.”
Driving interop, industry awareness
While Verizon has its own views about how NG-PON2 can impact its FTTP vision, the service provider is keen on sharing its findings with the larger service provider community. As the service provider has been testing NG-PON2 systems, it has been actively driving new interoperability standards other providers could use for their networks.
Verizon recently completed NG-PON2 interoperability with five vendors for its OpenOMCI (ONT Management and Control Interface) specification, bringing it one step closer toward achieving interoperable PON network systems.
After conducting an initial NG-PON2 trial in December 2016, the telco offered OpenOMCI specifications, which define the optical line terminal (OLT)-to-optical network terminal (ONT) interface to the larger telecom industry.
Working with vendor partners Adtran, Broadcom, Cortina Access, Ericsson/Calix and Intel, Verizon developed the OpenOMCI specification that led to what the telco said was a successful trial at its technology center in Waltham, Massachusetts, in May.
Deutsche Telekom, SK Telecom and Vodafone also participated in the trial as virtual observers.
“This defines specifications that ensure a vendor has no proprietary managed entities (MEs),” O’Byrne said in an earlier interview with FierceTelecom. “A vendor who is compliant with this has to support various MEs if they are supporting services like data or voice.”