CableLabs Qualifies First-Round DPoE Gear

The cable industry's drive to challenge the telcos in the enterprise sector and to grab a healthy slice of the growing cellular backhaul business took a big step forward this month as the first devices and systems were qualified for version 1.0 of the DPoE specification.The announcement was made by CableLabs on June 17. There were two types of qualified equipment: Systems from CommScope, Huawei, Sumitomo Electric and ZTE and optical network units from CTDI, Finisar, Huawei and Sumitomo.DPoE - DOCSIS Provisioning of Ethernet Passive Optical Networks - is an enabler. It is intended to extend the commands used to operate DOCSIS networks to EPON. These commands - be they in DOCSIS or DPoE - govern how configurations are downloaded to devices and the structure of the data that that is delivered. DPoE enables EPONs to use DOCSIS classifiers to control a number of key operations, such as service flows. The standard can, for instance, designate different quality of service levels for VoIP and video streaming and less demanding services such as email.DPoE therefore is a linchpin for both the core delivery of services and the ability to create and fulfill service level agreements (SLAs) that business customers demand. "The goal is to have the EPON work like a cable modem CMTS set up," said Tom Anderson, the director of product management for advanced broadband solutions for CommScope.The interoperability testing is designed to prove that it can work regardless of which vendors' gear is plugged in at any given point in this end-to-end system. "Interoperability is a key part of the qualification testing," said Curtis Knittle, CableLabs' director of digital video services. "We literally had four ONUs that were qualified connected to each of the four DPoE systems. Part of our testing was to have them mixed and matched throughout."Anderson said that in an EPON, the optical line terminal (OLT) is analogous the CMTS and the optical network unit (ONU) and optical network terminal (ONT) are analogous to the cable modem. "You plug a cable modem plug onto the cable network, and the network recognizes it; from there it goes onto a big server that finds out how it's supposed to be provisioned, maximum data rates, minimum data rates and so on. All that happens automatically. DPoE over EPON works the same way."To a great extent, DPoE will be most relevant to medium- and large-size businesses because they are far more likely to be served by an EPON system than residential customers or the small businesses that ride on the same networks, at least in the short term.The emergence of DOCSIS 3.1 won't impact DPoE, Anderson said. In essence, what happens to the DOCSIS standard itself isn't important to EPON as long as the provisioning and signaling elements don't change. One of the biggest advances in DOCSIS 3.1 is channel bonding. That isn't relevant to the fiber side of the equation since it is a variable bitrate technology that doesn't rely on traditional cable channelization.The Converged Cable Access Platform (CCAP), along with DPoE and DOCSIS 3.1, are the highlights of the cable industry's emerging technology portfolio. While DOCSIS 3.1 and DPoE and won't impact each other, DPoE and CCAP are more directly connected. As discussed during a breakfast presentation at the Cable Show in Washington, DC, on June 11, EPON eventually will be incorporated in the CCAP specification, which seeks to condense DOCSIS and video QAM functions.Carl Vassia, the General Manager of CTDI's Products Division Sales, said that the the two-fold benefits of DPoE – the ability leverage DOCSIS provisioning and the promise of interoperability between equipment -- is a major step. “I do believe DPoE is very important,” he said.Carl Weinschenk is the Senior Editor of Broadband Technology Report. Contact him at [email protected].