INSIDE
THIS issue
CT's
PON&RFoG
Tech Guide
Assessing, Glossary ..... page 1
PON/RFoG table............ page 3
Timeline, DOSIS/PON.... page 6
Venn diagram................ page 7
RFoG Overview & App...page 8
October 2008
Assessing PON and RFoG
this
complicated
networking
Glossary
standards
that
RFoG: Radio Frequency (RF) over
The cable industry is moving
through
toward the adoption of technical
landscape and shed some
emanated from two bodies.
glass. An acronym associated with
standards that would take the
light on options now facing
One family of standards or
both specific fiber-to-the-premises
“H” and “C” out of the hybrid
the industry.
officially recommendations—
products and an emerging stan-
asynchronous (A)PON issued
dard being developed within
fiber/coax (HFC) architecture.
While the likely near-term
Prophet before his time?
in 1996, broadband (B)PON in
working group 5 of the SCTE’s
application of these optical
A little history can offer a lot
19 9 8 a n d G i g a b i t ( G ) P O N
Interface Practices and In-Home
fiber
of perspective.
in 2003—emerged from proj-
Cabling Subcommittee (IPS SP
to niche markets, this attempt
It’s been eight years since
ects sponsored by the Interna-
910: “RF over Glass System
to forge a standard approach to
Jim
of
tional Telecommunications
Overview.”) In either case, this
fiber-to-the-premises
Modern
Television
Union-Telecommunications
technology involves transmitting
technology still represents a
Technology, departed Antec
Standardization Sector (ITU-T).
RF over fiber, instead of coaxial
remarkable turn for the industry.
to become CTO of FTTP
Another family derived from
cable, through splitters to a node
But it’s not happening within a
startup Wave7 Optics.
the Institute of Electrical and
or terminating unit deployed at
vacuum, and that complicates
In an interview at the time,
Electronics Engineers (IEEE),
the premises. It supports the use
matters. International standards
Farmer raised some of the
which got into the game in
of existing customer premises
for the larger passive optical
engineering
business
2001 with its 802.3ah or
equipment (SCTE55-1/55-2 set-top
networking
category
tradeoffs that led him to
Ethernet in the First Mile (EFM)
boxes and DOCSIS equipment).
already exist, and the range of
create something positioned
working group. That led to
It requires the addition of an
vendors with existing and
between PON, which then
approval of the Ethernet (E)
EDFA and return receiver in the
forthcoming solutions relevant
he regarded as too expensive,
PON standard in 2004.
hub to support bi-directional
to cable’s radio frequency
and HFC.
These
optical transport on an FTTH
over glass (RFoG) project is
“By strategically placing an
supported
wide and varied.
active device in the field,”
members of the ITU and IEEE,
and
Farmer said, “we can have the
were hard to ignore. Within
implementations vary. Data rates
suppliers have already launched
best of both worlds.”
two
are limited to existing DOCSIS
splitters,
network
It’s not just the relative lack
leaders
terminals and other products
of actives, of course, but
shift in course.
of
friendly to this effort. Others
also network smarts—such
The SCTE Advanced Plant
is required.
are engaged, but holding back
as
allocation
Architecture
Study
until the standard is more
algorithms—that make PONs
established
to
determine
PON: Passive optical network. Its
baked. Still other vendors have
what
the
standardization needs for the
distinguishing characteristic is
moved into this market from
ensuing years, Wave7 and
increased use of fiber in cable
point-to-multipoint (P2MP) with
the PON arena, which has
other vendors on the optical
plants,
inaugural
no elements between the hub
undergone its own twists
side of the aisle continued not
meeting at Cable-Tec Expo in
and customer premises except
and
only to increase those smarts
June 2006. And on Aug. 17,
for passive splitters. PON typi-
but
a
article
cally uses asynchronous time
appeared in the Wall Street
division multiple access (ATDMA)
standards
Some
is
(PON)
limited
(FTTP)
traditional
optical
turns
over
cable
the
past
several years.
This guide attempts to sort
Farmer,
co-author
Cable
and
bandwidth
they
also
are.
to
Over
adjust
their
platforms in conformance with
developments,
by
years,
participating
cable
began
held
industry
signaling
its
controversial
a
Group,
continued on page 3
point-to-multipoint plant. Proposed
existing
reverse
path
1.1/2.0/3.0 data rates and use
existing
DOCSIS
CMTS
continued on page 8
Cisco Prisma D-PON
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• Reductions in service group sizes in the headend without changes to the OSP
Prisma 1550nm
Optical Amp
The Cisco D-PON Optical Network Terminal (ONT) provides 19dBmV output, multiple
powering options, and 1310nm or 1610nm return paths.
The Cisco D-PON solution is the ideal union of the strength and widespread availability
of traditional HFC systems with the powerful potential and longevity of an all-fiber
DOCSIS-based network.
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Prisma D-PON
ONT
Assessing PON and RFOG
Vendor Name
RFoG Only
EPON Only
EPON+RFoG
continued from page 1
EPON
GPON
RFoG
Aurora Networks
l
Cisco Systems
(Scientific Atlanta)
l
Commscope
l
Corecess
Journal citing a CableLabs study
DPON
that indicated the industry might
need to take fiber to the home to
keep track with competitive threats,
such as that posed by Verizon’s
1
BPON-based FiOS initiative.
Over the following year, the
industry further warmed to the IEEE
perspective. Ethernet pioneer Bob
l
Metcalfe
UT Starcom
l
ZTE
l
Alloptic
l
l
Pacific Broadband
Networks
l
l
Comcast,
the
on
Technologies
in
SCTE
Emerging
January
2007.
Suddenlink,
Bright
House Networks and CableLabs
Enablence
(Wave 7 Optics)
l
l
l
Hitachi Telecomm
(Salira Systems)
l
l
l
l
l
Huawei
l
l
Nokia Siemens
Networks
l
l
EPON + GPON ECI Telecom
keynoted
Conference
joined
Cox
and Time Warner
Cable among other cable operators
as
members
Ethernet
of
Forum,
absorbed
the
the
Metro
which
EFM
had
Alliance
(803.ah). The MEF itself held its
first workshop at Cable-Tec Expo
l
in June that year.
Throughout
2007,
several
suppliers of EPON technology,
including Wave7 Optics, added
radio frequency (RF) functionality
to their platforms. In the fall
Motorola
l
of 2007, the SCTE Engineering
Alcatel-Lucent
l
Committee
RFoG
NOTES 1. Cisco Systems (Scientific Atlanta) previewed a "DPON" RFoG product in June 2007; Cisco also talked publicly in early 2008 of work on a true DOCSIS PON capable of delivering 1 to 10 Gbps cable modems.
2. This chart only lists GPON for EPON vendors that also offer GPON, it is not intended to be an exhaustive GPON vendor list. Missing would be Adtran, Alcatel-Lucent,Calix, TXP, NEC, Occam, Pannaway,Tellabs, and Zhone.
3. Likely future EPON vendors include: Alcatel-Lucent and Nokia Siemens Networks. Both companies are very active in P802.3av. Since neither currently offers an EPON product, the rational explanation is that they are either thinking about or actively planning such products.
4. This list does not include EPON vendors that do not offer products for sale in the US. There are a number of vendors that sell EPON products in Japan that do not offer them for sale in the US and do not want to sell or support those products in the US.
Table 1: Vendor Portfolio PON/RFoG Matrix
editorial
editor Jonathan Tombes
(301) 354-1795, jtombes@accessintel.com
managing editor Ron Hendrickson
(303) 422-3373, rhendrickson@accessintel.com
contributing analyst Victor Blake
approved
project,
and
the
work
formally began within working group
(WG)
5
Practices
of
the
Interface
Subcommittee
(IPS)
in March 2008.
Across
Farmer,
was
this
eight-year
whose
acquired
Technologies
by
in
span,
company
Enablence
May
2008,
continued to speak at cable industry
gatherings. His paper at this year’s
Cable Show, for instance, contained
a figure that formed the inspiration
for
the
timeline
on
page
6
design/production
senior art director Tzaddi Andoque (301) 354-1677
senior production manager John Blaylock-Cooke
(212) 621-4655
Access Intelligence
4 Choke Cherry Road, 2nd Floor, Rockville, Maryland 20850
3
higher RF Signal to Noise Ratio
specifically to meet the unique
Blake argues, however, that
analyst Victor Blake.
(SNR) than natively over coax.
needs of cable operators for
GPON’s sole adoption by
Farmer’s paper was also the
From a vendor perspective,
new build applications.”
Verizon, and EPON’s rapid
basis for a column that first
some existing pre-standard
Others
have
appeared in the July issue of
solutions look familiar enough.
products
aimed
C o m m u n i c a t i o n s
The catalog for Commscope’s
BrightPath
compiled
by
independent
in
Technology,
which
he
a
standard
with
At Cable-Tec Expo in June,
widespread
deployment,
Motorola
that
particularly in Asia, marks
Compton
EPON as the winner. Then
had
there is the matter of the
announced
Canadian-based
its
several
operators
“RF over Glass Overview.”
deployed and and trialed,
selected
FTTH
ITU-T study group 15 agreeing
features
tap,
GPON-based technology. At
with the IEEE on a converged
network interface unit (NIU),
Cable-Tec Expo in 2007, the
PON
attending
but
to
cable
these
suppliers
to
technology
are
inclined
emphasize
constraints
particular to the industry.
“The
has
realm
very
of
unique
HFC
optical
requirements and requires
very
of
careful
the
interpretation
laws
of
(MSOs)
an
have
optical
Communications
its
standard
"The realm of HFC has very unique
requirements and requires very careful
interpretation of the laws of physics,"
– Bill Dawson, ARRIS
physics,”
Scientific
conduit
of
ARRIS
node from standing partner
previewed
transport division.
Aurora Networks.
calling
Whereas in the telephony
At Cable-Tec expo in June
which
world, optics have traditionally
2008, Harmonic announced
RFoG standard, aimed at l
will
been an on/off phenomenon,
that it also had teamed with
everaging
and RFoG projects.
Dawson
Commscope
infrastructure.
Bill
Dawson,
vice
access
said
and
that
cable’s
and
an
to
optical
make
its
Atlanta
Cisco
branch
on IEEE P802.av. (See Figure
backup power, optical cables,
president product strategy,
said
based
are
meetings,
incumbent
system
as
SCTE work on IPS SP 910, or
Newcomers
multiple
which
evolution
combined
cable.
encouraged others to join the
Vendor mix
Systems
what
it
DOCSIS
like
(D)PON,
the
emerging
cable’s
1, p. 6.)
was
existing
Cost structure
It’s safe to bet that economics
drive
both
ARRIS’s
the
Dawson
points
MAXLink forward transmitters
The use of that acronym
to
“presents
and return path receivers com-
is
confusing,
equipment (CPE), as it bears
patible with the BrightPath
however,
discussion
the “lion’s share of the cost ”
system.
of using DOCSIS over a
Given that the CPE in
a
whole
new
“RFoG
bridge
is
actually
between
the
a
two
worlds,” he said.
potentially
given
more classic PON technology.
a
network interface device (NID)
For
Introducing
a
new
RFoG
premise
framework
a
is
a
paper
essentially
the
SCTE
little node with correspond-
instance,
sophisticated
strategy
at Cable-Tec Expo in June,
presented
entails building outside plant
Commscope Vice President
ET Conference in January
ingly
components in such a way
Marketing and New Business
2008
for
that a seamless switch to
Development Carl Meyerhoefer
Architect
EPON or GPON electronics is
underscored industry ties.
and
(MTBF),
optimizing
possible down the road.
“We
closely
Engineer Steve Gorshe, and
demands
of
The cable-friendly aspect of
with cable operators to under-
adapted for publication in the
and
RFoG
stand
at
February
issue
of
CT,
trivial task.
pure
the customer premises and
proposed
combining
the
“If
for
incorporated that feedback
best of DOCSIS and either
successful,
instance, it is likely that
into this new NID design,”
GPON or EPON.
because the necessary ele-
DOCSIS
Meyerhoefer
Which of those PONs is
ments are in place to drive
ascendant
the cost of the CPE down,”
The
its
migration
technology
appeal.
technical
From
has
a
standpoint,
upstream
will
worked
the
needs
said
a
Software
Bernstein
PMC-Sierra
is
Principal
a
matter
statement.
than HFC, because the optical
fiber-to-the-home (FTTH) solu-
of
transport
tion, he added, was “designed
Independent analyst Victor
support
a
overall
Cisco
Alon
perform faster under RFoG
will
The
in
by
at
consumer
PON
analog modulation of light
dimension of challenges.”
4
system,
launched
at
some
speculation
high
requirements
reliability
and
mean times between failure
manufacturing
RFoG
the
engineering
is
no
is
to
be
that
will
be
he said.
—Jonathan Tombes
the FTTH
solution that
fits perfectly
with existing
HFC
Back-Up
Power Supply
FTTH made simple!
TM
Node
BrightPath is a simple approach to FTTH, employing reliable
technology and standard cable installation practices to allow
cable operators to deploy FTTH in new build areas without
altering existing infrastructure.
TM
Figure 2: xxx
Fiber Drop
Armored
Cable
Tap
- This cost effective alternative to a PON can be installed as
needed within an HFC network
- The total system cost is highly competitive with advanced
HFC systems
Fiber Flat
Drop Cable
in Conduit
NID
- Another innovation from a business partner you already trust
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®
800.982.1708
©2008, CommScope, Inc. All Rights Reserved.
5
TPON
British Telecom
(BT)
ITU-T G.982
Defined the ‘ODN’ for
1550nm/1310nm ‘WDM’
P2MP diplex
Telephone PON
One PSTN line
● One control line
● One broadcast 18 channels lamda
●
1990
●
1990’s
PiPON
●
●
NTT
Japan
Simplex Data
Video Broadcast
ISDN Framing
1993
64kbps to 1.5Mbps
● No overlay
●
APON
1996
ATM Framing
No overlay
● 155/155
● 622/155
● 1.24/622 and 1.24/1.24
●
●
ITU-T G.983
G.982 Based w/ATM
622/155Mbps was one of
a few options
ITU-T G.983.3
1550nm overlay
ITU-T G.984
G.981/982/983
Based on ATM
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
BPON
1550nm overlay for broadcast
No overlay
● 622/155
●
●
GPON
ATM/TDM
● 1550nm overlay for broadcast
● 2.488Gbs/1.24Gbs
●
GPON ‘Lite’
Ethernet transport via
‘GEM’ encapsulation
● Broadband Forum replacement
of ITU-T provisioning in 2007
●
ITU-T SG15 & IEEE
Agree on 10Gbps/10Bps
Converged PON Standard
based on the work of P802.3av
EPON
1550nm overlay
● 100Mbps symmetric
●
IEEE
GEPON
●
●
802.3ah
Ethernet in the First Mile (EFM)
1550nm overlay
1Gbps symmetric
10Gbps EPON
Backwards compatible with EPON
and GEPON with lamda overlay
● Initially 10 Gbps/1Gbps
● Later 10Gbps/10Gbps
●
IEEE
P802.3av
RFoG
Likely two versions
EPON Compatible
● Stand-alone RFoG ONLY
●
●
SCTE
IPS 910
WG5
FUTURE
NG PON
Q: Shall there be a next generation
PON recommendation?
10Gbps EPON
Backwards compatible with EPON and GEPON with lamda overlay
QAM Hooks for FSAN (GPON OAMP Compatibility)
● 10Gbps/10Gbps
●
●
Figure 1: Timeline on ITU-T, IEEE and SCTE PON standards projects
PON and DOCSIS
"Chasing
tion of Internet protocol (IP)/
IP service architecture and
telcos are building a service
Verizon FiOS: The Race is
Internet/Ethernet architecture,
even the fiber distribution
overlay standard for GPON
On,"
Blake,
for instance, was much more
plant for 1,550 nm forward
that they call FSAN. The cable
Communications Technology,
rapid and thorough than its
video broadcast. While there
community must build an
August 2008. Drawn from
telco competitors. With voice
are some small challenges for
overlay for EPON. DOCSIS is
paper presented at SCTE
service, cable operators adopt-
two-way
return,
the natural candidate to hide
Cable-Tec Expo.
ed voice over IP (VoIP) to the
the bulk of the technical
the new EPON PHY/media
customer
challenge is in operations,
access control (MAC) layers.
Excerpted
6
from
by
Victor
premises
long
video
DOCSIS OAMP
before telcos.
administration, maintenance
The cable operator community
EPON will be a similar chal-
and provisioning (OAMP).
Common interfaces
has distinguished itself as a
lenge for cable. There is no
IEEE 802.3ah and 802.3av
As in previous cases, cable
strong proponent of IEEE and
technology risk as to whether
are Ethernet protocols just like
operators can work together
Internet
Task
it will work. Like VoIP, it is a
802.3z (GigE). They are access
to develop a common service
Force industry standard tech-
cost-effective solution than
protocols that lack service
interface for EPON that meets
nologies. Cable operator adop-
can be integrated with existing
provider-specific OAMP. The
specific needs. DOCSIS over
Engineering
PacketCable
RFoG
EPON
ECI
Corecess
PBN
Alloptic
Huawei
ZTE
W7/Enblence
UT Starcom
Aurora
Commscope
Cisco/SA
Salira/
Hitachi
DOCSIS over EPON
(DPON)
Figure 2: Current EPON, RFoG and DOCSIS over PON
vendor portfolios
Multimedia
is
the
service
(SID).
integrate any additional appli-
that EPON uses a logical link
cations with service agnostic
identifier (LLID) as its single,
quality of service (QoS).
cross-layer service system,
DOCSIS is vertically inte-
just as the SID in DOCSIS.
grated. It includes the service
The LLID can do everything a
overlay layers, the MAC, and
SID can do. Just like SIDs,
the various PHYs. Though it
LLIDs are deterministic and
was originally organized as a
strictly scheduled. They are
vertically integrated protocol
not probabilistic (like 802.1p
family, we can identify open
and
systems interconnection (OSI)-
schemes).
like boundaries that separate
Operationally, cable opera-
the MAC from the PHY and
tors can build an even more
the service control from the
competitive edge through the
MAC. These layers have been
adoption of DOCSIS over EPON
peeled away further as we
technology to extend OSS
have added new PHYs such as
support to include high-end
synchronous
division
Ethernet services for business
(SCDMA)
customers. With a combination
multiple
code
access
It
other
is
no
identifier
(PCMM), cable operators can
QoS
accident
queuing
EPON is this effort.
nology. Within the DOCSIS
in 2.0, and later the MULPI
of
It is a competitive advantage
family, there is imbedded, best-
overlays in 3.0.
DOCSIS over EPON, the exist-
that cable operators already
effort, high-speed data service
have in DOCSIS a strong and
and voice with PacketCable 1.5.
Service Identifier
competitive edge for cable
mature service overlay tech-
With PacketCable 2.0 and
The one cross-layer technology
competition with FiOS.
ARRIS_PON_ad_v4.indd 1
ing
MEF on DOCSIS and
OSS
can
further
the
8/8/08 4:04:14 PM
7
RFoG Overview and Application
From “RF over Glass for
ment
Business
such as analog, digital, and
Michael
Services,”
J.
by
Emmendorfer,
(CPE)
services
DOCSIS services.
alternative
outside plant….
to
traditional
fiber solutions.
APPlications
The
use
of
RFoG
and
senior director, solution archi-
An RFoG service group size
...The emergence of RFoG
DOCSIS may be an excellent
tecture and strategy, ARRIS.
will likely be in the range of 32
enables a fiber-to-the-business
combination
Published in January 2008,
homes
(FTTB) or fiber-to-the-home
includes
Communications
Technology.
combining at the headend will
(FTTH)
passive
optical
Drawn from a paper presented at
remain an option as with
network
solution
use
the business, which incorpo-
the SCTE Symposium on Business
traditional HFC. This allows
all-passive fiber networking
rates the redundancy schemes
Services, October 2007.
CMTS equipment to be shared
that
found on high-end CMTS
over a larger pool of service
traditionally
over
equipment. These redundancy
OVERVIEW
groups
HFC. These services include
schemes may not always
...The SCTE Advanced Plant
economies of scale.
the carriage of analog and
be
Architecture Study Group is
The
digital services as well as
switching or PON network ele-
using the term RFoG. The RFoG
RFoG
the transport of data and
ments. The business service
solution uses existing business
service providers deploying an
voice services over DOCSIS.
unit
support
system/operational
all-passive optical network,
If an operator prefers to
back office implications of
support system (BSS/OSS) and
like RFoG or passive optical
deploy
each
headend
network
systems,
resolve operational concerns
alternative
cable operator’s network. The
which find lower operational
regarding active outside plant
costs and time to market
traditional cable installation
costs than fiber-to-the-node
or to support future capacity
to
practices are leveraged as well
approaches
actives
growth
explosive
as customer premises equip-
or
in
the
customer, RFoG may offer an
coming years…
scheduling technology to trans-
and 155 Mbps on 1,310 nm
all new deployments in early
already have deployed EPON
port data from an optical line
upstream. It is the PON standard
2008.
to serve business customers.
termination (OLT) device to a
that Verizon initially deployed
Group 15) has adopted IEEE
set number of optical network
with FiOS until approximately
10GigEPON
(P802.3av)
DPON or DEPON: DOCIS over
termination (ONT) units at the
November of 2007. Its succes-
as the foundation for its
EPON. A combination of EPON
premises.
sor is ITU-T G.984 (GPON).
Next Generation (NG-PON)
and DOCSIS that leverages
nals are combined using a
recommendations.
a cable operator’s DOCSIS
multiple
GPON: Gigabit PON (ITU-T
elements…in
Glossary
for
however,
even
reasoning
may
be
behind
found
(PON)
with
copper
greater
wiring
in
carries
optical
to
all
services
delivered
fiber
of
solutions
the
to
business
because
an
network
available
will
direct
on
network
to
Ethernet
also
consider
technology
and
support
this
all-passive
the
the
expected
growth
in
continued from page 1
Upstream
access
the
passed;
sig-
protocol.
ITU-T
SG15
(Study
networks
and
operational
It is contrasted with more
G.984);
EPON: Ethernet PON (IEEE
support
capital-intensive point-to-point
to BPON. It provides for
802.3ah).
initially
While RFoG relies on a CMTS
(P2P) architectures.
transport
the
of
transfer
8
and
successor
EPON
systems
(OSSs).
supported 100 Mbps symmet-
and RF transport (over optical),
(ATM),
ric and has evolved as Gigabit
DPON moves the compatibil-
multiplexing
asynchronous
mode
BPON: Broadband PON. One
time
Ethernet (sometimes called
ity back to the OSS interfaces,
of three PON recommenda-
(TDM)
but
GE-PON) to support 1 Gbps
making an EPON OLT look
tions issued by the International
has effectively shifted over
symmetrical, with dual-speed
and act like a CMTS. While
Telecommunications
Union,
several years to primarily an
EPONs capable of 2.5 Gbps/1
eliminating
BPON (ITU-T G.983) is the
Ethernet standard, operating
Gbps. The IEEE 10 Gbps
the DOCSIS CMTS, it offers
successor to asynchronous
at 2.488 Gbps downstream
EPON study group (P802.3av)
seamless
PON (APON). BPON sup-
and 1.244 Gbps upstream.
is completing work on the
provisioning and operations.
ports the 1550m broadcast
Verizon
deploy-
first 10G/1G standard, with
Unlike RFoG, it will sup-
overlay. It specifies 622 Mbps
ing GPON in late 2007 and
chipsets expected in 2009.
port EPON data rates up to
downstream data on 1,490 nm
standardized on GPON for
A number of cable operators
10Gbps/1Gbps.
division
and
Ethernet,
began
the
need
compatibility
for
for