This Week’s Translation Dips Into The Terminology
of cable-provided services to businesses
— a wonky pedigree of tech talk,
but important as the Next Big Thing to
We’ll start with “DPoE,” a doublenested
acronym that stands for “DOCSIS
Provisioning of EPON.” Some pronounce it
as a word, like “depot,” others as its constituent
DOCSIS means through the cablemodem
side of the plant. EPON stands for
Ethernet Passive Optical Networks, techspeak
for running Ethernet over a length
of fiber attached directly to a business.
Right now, cable isn’t as active in providing EPON
connectivity as it could be. (Bright House Networks is the
Yet, EPON is big business. It’s what more and more
commercial accounts want to use for their fast broadband
connections. That’s “fast” as in 1 Gbps, which is the same
as 1,000 Mbps. (For context, even the fastest residential
broadband connections top out at around 50 Mbps.)
Know going in that DPoE is less about the pipe and more
about the process. That means it’s not concerned with the
bandwidth of delivering 1 Gbps so much as automating the
back-office components to serve it. It’s a provisioning thing,
intended to quickly and affordably set up new business
customers with high-speed links, over fiber.
DPoE didn’t start out with an automation concentration,
though. As the story goes, a bunch of engineers were working
with the EPON vendor community, which had agreed to
make their stuff interoperable with each other — that vendor
A’s “OLT” (optical line terminal) would work with vendor
B, C, D or E’s “ONU” (optical network unit, the thing that sits
at the customer site).
Despite good intentions, the gear wasn’t interoperable.
Further investigation revealed problems in what cable people
call “the back office,” and telco people call “OAM” — for
“operations, administration and maintenance.”
That’s what lit up the “why-reinvent-the-wheel?” lightbulb.
DOCSIS already contains ways to automatically provision for
such “OAM”-ish checklist items, they reckoned. (Advanced
class: things like DNS, DHCP, TFTP and SNMP.)
In essence, and in a huge oversimplification, DPoE
spoofs the DOCSIS back-office components into thinking
that an EPON OLT is a CMTS, and that an EPON ONU is a
It translates between the EPON system and the DOCSIS
In the near future (2011, by most estimates), cable providers
will be able to add EPON technologies to support their suite
of products for businesses. That’s a good thing for ka-ching.
One catch: DPoE assumes there’s fiber connected to
EPON-interested businesses. That’s often not the case.
Still, it shows every sign of big-revenue potential for the
growth of cable-delivered commercial services.