broadband work - VIAVI Solutions Inc.

broadband work - VIAVI Solutions Inc.
broadband work
Tools to Help You Put Broadband to the Test
JDSU can help you save time and money with your broadband deployment—
end to end, across the network, and throughout the network life cycle
[email protected] Across America
The American Recovery and Reinvestment Act provides much needed
funding to expand broadband access to rural and underserved communities
across America.
For these communities, access to high-speed data, voice, and video services
offers job creation and economic development benefits. Individuals can
grow web-based businesses, take advantage of telemedicine and distancelearning applications, and enjoy more home entertainment options. As
service providers, you will play the critical role in accelerating broadband
deployment for more American communities.
This is a historic opportunity to bring the benefits of broadband to the
one-third of Americans who currently do not have broadband access.
Whether you are deploying fiber-to-the-home (FTTH), digital subscriber
line (DSL), wireless, hybrid fiber-coaxial systems, or broadband over
power lines you need the tools and expertise to install, test, and verify
infrastructure and services efficiently and cost-effectively.
This is where we can help you. As a leader in broadband network test and
measurement solutions and optical components, JDSU has decades of
experience working with large and small telecom service providers,
cable operators, utilities, municipalities, and network equipment
manufacturers. With JDSU, you have a partner who can help you get it
right the first time—saving time and money. Our [email protected] tips
located throughout this document reflect years of experience working
with next-generation broadband networks and equipment.
Will Your Network Pass the Test?
As millions of Americans watch video over the web, download music and
video, and send increasingly large files, today’s broadband networks have
to meet increasingly stringent tests. For service providers, you have to
deliver high-quality service at an affordable price. You need the knowledge,
tools, and solutions to:
Build new broadband access networks
Understand what can go wrong
Detect common problems
Fix network and installation problems
Ensure reliable service
Here are solutions to some of the more common issues and problems service providers face when deploying FTTx
networks and providing broadband services:
Potential Problem
Test Solution
Installing Fiber
Dirt contaminates the line and can damage
the equipment
An all-in-one test instrument that serves as a
power meter for turning up fiber and also inspects
the fiber for dirt contamination
Deploying Ethernet Equipment
Configuration errors in Ethernet switches
and routers lead to frame loss and delay
Ethernet testers that enable technicians to verify
the Ethernet link and configuration in the
central office and video serving and hub offices
Identifying and Solving
DSL Service Problems
Wideband and impulse noise impairments
impede service quality
Application aware test solutions that can test
multiple layers at the same location and time
to identify and solve the service problem
Processing Video
Signal delays can cause synchronization
issues for video and its audio timing
Video analyzers that measure timing accuracy,
jitter, and drift to ensure nanosecond resolution
Installing CM service with margin
Leaving the home without conducting
proper tests can cause data service
problems later resulting in customer
dissatisfaction and repeat truck rolls
DOCSIS®-capable triple-play instrument that
measures all key digital parameters including
two-way DOCSIS communication tests to ensure
there is some margin before services can be affected
Inside the New Broadband Network
Today’s broadband network
represents four key components:
Regional/Long Haul
Optical Amp
Regional/Long Haul and
Metro Networks
the fiber optic and network
switching core network as well
as the network connecting two
or more local area networks,
using multiple access methods to
carry voice, video, image, and
multimedia data
Optical Amp
Access Network
the broadband access
technologies connecting a
customer location to the
network switch or points of
the broadband devices and
services used by a customer in
the home, office, and mobile
As a provider, whether you are
directly responsible for all or just a
portion of these network
components, you need a strategy
that guarantees quality of service
(QoS) end to end and throughout
the network life cycle—from design
to operation—to give your
customers the broadband service
they require.
To Cable Modem
Enterprise Network
Home Network
To DSL Modem
To Business
Lighting the Way with Fiber in the “Last Mile”
Ensuring End-to-End Performance
Use a Power Meter to Test Passive
Optical Network Installations and
Inspect Before You Connect
Optical line terminal (OLT)
installation at the headend or CO to
customer premises are key in building
the PON. Upon completion and turnup, the technician may opt to perform
power level checks at the OLT or FDH
and the other unit to the fiber to the
ONT. A power meter is used to
measure and verify adequate power
flows in both directions. If a problem
is detected, the technician can then
use an OTDR to troubleshoot the
network segment. Various OTDR
configurations may be utilized
depending upon network topology
and test point access.
Pushing optical fiber much deeper into the access network, in some cases
all the way to the customer premises, is an important part of the strategy
of nearly every service provider. Passive optical networks (PONs), pointto-point, and other types of fiber optic infrastructure offer the potential
for practically unlimited bandwidth and also facilitate greater control over
the operation, administration, and provisioning of the access network.
Testing PON Frame Installation and Connection
At the fiber distribution hub (FDH), all fibers coming from the central
office (CO) are connected to splitters. An optical time domain
reflectometry (OTDR) measurement from the CO is recommended to
verify splice quality out to the hub, ensuring all fibers are connected to the
network. A measurement at 1310/1550 nm is then performed from the
hub downstream to check fiber and splice quality.
Testing at the Curb and/or Customer Premises
At the curb or junction box, prior to connecting the drop cable and at the side
of the house, prior to connecting the drop to the optical termination unit
(ONT), the technician should check optical power levels and inspect the
connectors for dirt or contaminants prior to connecting. These quick and
easy-to-perform steps are essential—if problems arise later during the
installation, any issues with the fiber plant have already been ruled out and the
root issue is either inside the home or upstream in the network.
Inspect Before You Connect
When time is money, it makes sense to inspect
before you connect. An OTDR test tool is
essential for verifying proper continuity after
fusion splicing for feeder or distribution
networks. A uni- or bidirectional OTDR
measurement from the CO at 1310/1550 nm
can be used to qualify the fiber and splices.
Actual laying of the fiber may be outsourced in
some deployments so that the technician
performing the install may need only to test
the power level and connectors. In other cases,
one person might be responsible for the entire
job and need only an OTDR, power meter, and
connector inspection scope.
Making the DSL Triple Play
Sectionalize and Isolate
DSL Problems
Application-aware test solutions that
can test multiple layers at the same
location at the same time can aid
greatly in isolating problems in
smaller networks where there is less
rigid separation of work responsibility and no large network
operations center to monitor every
corner of the network. For example,
if you have a customer who is
experiencing video degradation on
IPTV service delivered over DSL,
you can test the service to make sure
it is running clean to the house and
upstream to the network.
As DSL technology has evolved from asymmetric DSL (ADSL) to ADSL2+
to very high-speed DSL (VDSL2), it has demonstrated the ability to deliver
ever increasing data rates—enough to deliver triple-play voice, video, and
data services. The high data rates used to deliver broadband services such as
Internet Protocol TV (IPTV) place far more demands on the existing copper
plant than plain old telephone service (POTS) or even first-generation
ADSL-based Internet. Pushing the rate and reach curve to offer video and
high-speed data over the copper plant increases the sophistication of the
testing required to ensure quality of experience (QoE) and QoS.
Addressing Bridged Tap, Wet Sections, and Metallic Faults
Because an earlier generation of Internet data service was less than 1.5 Mbps,
common faults and impairments such as bridged taps, wet sections, and
metallic faults often did not prevent achievement of the minimum required
ADSL sync speed. But these previously marginal conditions usually have a
much larger impact on high-speed and video performance. A comprehensive
automated pair-check test takes the guesswork out of prequalification and
troubleshooting by proactively identifying, locating, and removing these
Detecting Wideband and Impulse Noise
Wideband and impulse noise conditions that were marginal when there
were only a few working DSL pairs in the cable can become sources of
trouble as the number of subscribers increases over time. Additionally,
these problems can be intermittent in nature, making them harder to
diagnose. The ability to measure wideband and impulse noise in snapshot
mode and over time as well as the ability to analyze the noise spectrum
over time are essential troubleshooting tools.
Ensuring Performance of HFC Access Networks
Engineers and technicians struggling with assignments as diverse as
tracking down and fixing ingress, aligning optical nodes, and providing
proof of performance need easy, cost-effective methods for efficient
installation, qualification, maintenance, and troubleshooting of Hybrid
Fiber Coaxial (HFC) networks.
Use Sweep to Maintain
Peak Performance of Your
HFC Network
One core requirement of any HFC
network with two-way services is
ensuring sound HFC frequency
response in both the forward and
return paths. Service quality
depends upon signals with the best
SNR and the lowest intermodulation
distortion. The majority of all
transmission errors, including digital
carriers, can be detected by
measuring the frequency response of
the transmitted signals. Because
sweep results are independent of
transmission methods and formats,
they provide the most effective and
efficient method for technicians to
set up amplifiers with the right gain
versus frequency.
Troubleshooting Return Path Ingress and Noise Problems
The number one challenge for cable operators in maintaining high-quality
two-way communication services is detecting and resolving return path
ingress and noise problems quickly before they negatively impact the
customer. Because return path noise aggregates from each house when it
returns to the headend, high ingress from one house can degrade the data
reliability and quality of the entire node. In order to solve these problems,
operators need a return path monitoring and maintenance system
powerful enough to simultaneously monitor performance of the HFC
return path while supporting field and network operations center (NOC)
troubleshooting. It increases network availability for two-way services and
helps to retain the most profitable customers by easily detecting impulse
noise, ingress, and critical path delay (CPD) on all nodes before service
quality is affected. The system also accelerates troubleshooting without
impairing monitoring functions or headend personnel by broadcasting live
spectrum to the field technicians.
Measurements for DOCSIS Data Carrier Health
High packet loss as well as low throughput speeds many times are caused
by low downstream carrier quality and poor transmit level at the customer
premises. Digital quality measurements can typically reveal downstream
carrier quality problems which causes download speed and VoIP call issues.
The modulation error ratio (MER) is a measure of the signal-to-noise ratio
(SNR) in a digitally modulated signal and is good for showing consistent
issues such as a constant ingress spike. Bit error rate (BER) measurement is
good for detecting intermittent ingress issues. The cable modem range test
can measure the return transmit level, which will communicate with the
headend cable modem termination system (CMTS) to show how much
margin remains before communications become disabled. When the
transmit level is at its maximum, data link loss can result when the loss from
the customer premises to the headend becomes slightly larger. If the
transmit level is too low, ingress from the customer premises will have an
increased effect on data link reliability due to low MER.
Ensuring Performance of the In-home Network
Proactively Test Coaxial Cable to
Prevent Video over Data (VOD)
Coaxial cable faults and splitters that
create excessive loss or noise ingress
conditions can reduce the SNR,
leading to video packet loss and
degradation of the video service.
One common scenario exists where
broadcast video is delivered using
traditional QAM RF technology and
video on demand (VoD) service is
delivered as a separate IPTV stream.
The broadcast QAM RF video
generally has more robust forward
error correction than typical IPbased VoD, so fault conditions on
the cable can then lead to the
difficult to diagnosis situation where
the broadcast video works fine but
the VoD service is degraded—on the
same TV. Proactive testing of coaxial
cable runs within the home can
prevent this scenario from turning
into a trouble call later. When
troubleshooting, the ability to
quickly isolate the problem to the
physical coaxial cable media and
reliably locate the affected leg or
fault saves time.
A wide range of technologies—Multimedia over Coax Alliance (MoCA),
HomePNA, Data-Over-Cable Service Interface Specification (DOCSIS),
HomePlug, WiFi, Ethernet, and traditional quadrature amplitude
modulation (QAM) RF video signals—can be employed in the home.
Depending upon the technology, a range of different physical media—
coax; category 3, 5, and 6 cable; wireless; home power lines—are used to
get content to the physical user.
Spotting WiFi Problems
WiFi is the dominant method of in-home broadband Internet data
distribution. Typically, non-hardware-failure-related WiFi problems such
as weak signal, same channel interference, or encryption problems account
for as much as 20 percent of in-home “can’t connect” or “slow
connectivity” problems. The ability to systematically and efficiently
identify and resolve these problems is critical to controlling service costs.
Mapping In-home Infrastructure
Some in-house coaxial and twisted pair networks have undergone several
generations of change and expansion as residents switch between cable and
satellite providers and add their own runs. Trying to make sense of the
infrastructure under these circumstances can be a time-consuming, trialand-error process. Tools that allow the installer to quickly map the in-home
infrastructure and locate splitters, faults, un-terminated runs and other
issues such as satellite boxes still connected to runs, and saves time and
reduces the potential for problems later.
Homework for the Home
As much as 80 percent or more of post-installation problems with triple-play
service results from issues in the in-home environment. A systematic method of
diagnosing these problems is essential to avoid wasted time, effort, and money.
Carrying Broadband Services through Metro Regional Networks
Use an Ethernet Tester for
Configuration errors in Ethernet
switches and routers can lead to
frame loss, delay, and variation with
significant impact on video quality.
Ethernet testers enable technicians to
verify the Ethernet link and
transport layer configuration in the
CO, video serving offices, and video
hub offices.
Whether you are building out your own metro regional networks or using
a partner network to carry broadband services from providers to your edge
networks, ensuring transport quality will be key for successful broadband
service deployment. Metro core networks increasingly use IP/Ethernet as a
preferred transport technology.
Testing Ethernet to the Edge
Metro IP networks are prone to packet loss so verification of packet and
transport networks is critical to detect any quality degradation that will
affect the customers’ QoE and QoS. Ethernet is the preferred solution for
metro/edge/hub transport networks. Operators require the capability of
testing Ethernet networks for appropriate delivery of agreed QoS features.
Validating Link and Transport Quality
Configuration errors in Ethernet switches and routers link and transport
layer parameters can lead to frame loss, frame delay, and frame delay
variation with significant impact on video quality. Ethernet testers enable
technicians to verify the Ethernet link and transport layer configuration in
the CO, video serving offices, and video hub offices.
Verifying Video Transport Stream Quality
Intermittent frame loss and delay variation can also impact the video
transport stream quality. IP video testing at Ethernet switches verifies
quality of Motion Piture Experts Group (MPEG) transport streams.
Resolving Headend and Core Issues for High-Quality Video
Each stage of broadband service delivery introduces a different set of criteria to validate and different potential issues
to address. The service provider must validate both the physical plant’s ability to carry the bandwidth and the content
leaving the producer and entering the operator’s headend to detect fault conditions. This is true especially for fastgrowing video applications.
Validating Source Video Quality
Video streams need to be analyzed as they enter the headend prior to encoding to detect problems such as macro
blocking, blur, and jerkiness. A digital broadcast test platform can provide real-time analysis to ensure the source video
is error-free before it is encoded, multiplexed, or modulated for distribution.
Ensuring Proper Network Element Configuration
When multiplexing and mapping programs, it is vital to ensure that programs are where they are supposed to be and
properly reflected in the program association table and program map table. An analyzer compares the input of the
multiplexer with its output to continuously ensure that the configuration is correct and content is properly mapped.
Monitoring Digital Program Insertion
Because network operators increasingly are utilizing Digital Program Insertion (DPI) to maximize advertising revenue,
problems can quickly affect the bottom line. Test equipment should enable you to efficiently test DPI broadcast
equipment and monitor and troubleshoot associated MPEG streams with DPI data. This approach rapidly tests
message formats and identifies errors in splice points or DPI tables, protecting an important revenue source.
Validate Video Timing and
Any time video is processed, there are
delays in the signal. Ensuring the
health of the reference timing involves
more than simple jitter measurements. The MPEG analyzer measures
timing accuracy, jitter, and drift with
nanosecond resolution. The ability to
compare video and audio timing is
critical to diagnose lip-sync issues.
Intermittent frame loss and delay
variation can also impact the video
transport stream quality. IP video tests
at Ethernet switches verify quality of
MPEG transport streams.
An Elementary Stream Analyzer can be used to test the compressed video frame by frame to
identify violations of encoding specifications and provide detailed information about the
frames, macro blocks, motion vectors, and other compression parameters.
Assessing Your Network and Enhancing Service Performance
Broadband deployment poses many challenges to service providers.
JDSU has extensive experience working with service providers to create and
optimize operational procedures that enable reliable delivery of advanced
services. JDSU emphasizes deployment methodologies that help you easily
deploy and get services to market quickly and ensure high service quality all
with cost-effective support.
Phase 1—Network and Infrastructure Audit
The JDSU Professional Services team conducts an audit of your network
and operational infrastructure to identify potential issues and their root
causes to ensure achievement of your business objectives. These issues
range from network and system architectural flaws to lack of proper
surveillance systems and operational procedures.
Phase 2—Field Testing and Verification
JDSU performs a set of targeted field tests to isolate root causes of faults
and to determine specific actions for isolating issues identified during the
audit phase. The actions include preparing test plans, conducting tests,
and performing post-test analysis.
Phase 3—Analysis, Modeling, and Recommendation
In the final phase, JDSU provides recommendations with specific action
items to ensure your network, service architecture, and operational
process and practices are maximized for efficient operation.
In addition, we offer various consulting services to address the specific
challenges of deploying and maintaining broadband technologies with a
phased program to enable operators to cost-effectively deliver high-quality
Qualify and Validate Your
Fiber Plant
The new generation of broadband
networks makes it essential to go
beyond basic testing to qualify and
validate the fiber plant operation at
higher speeds to support dense
wavelength division multiplexing
(DWDM) and reconfigurable optical
add-drop multiplexer (ROADM)
upgrades. Characterizing your fiber
links allows you to determine which
links can support which speeds to
easily evaluate older fiber plants, make
evaluations when acquiring plants,
and make upgrade plans. In many
rural area build-outs, coarse wavelength division multiplexing (CWDM)
provides more moderate bandwidth
upgrades at a lower cost with relative
ease of deployment.
A Trusted and Tested Broadband Partner
broadband work
As you build and operate your broadband network, you can count
on JDSU as a valued partner. With more than 175 patents, an installed base
of more than 400,000 test instruments, and an extensive test and
measurement portfolio, JDSU offers you the expertise and experience to
meet all of your broadband needs.
From testing 100G optical network technology in our labs to providing
service providers with an array of test instruments for a range of broadband
technologies, our goal is to help you save time and money while delivering
the highest quality services.
Test & Measurement Regional Sales
TOLL FREE : 1 866 228 3762
FAX : +1 301 353 9216
TEL : +1 954 688 5660
FAX : +1 954 345 4668
TEL : +852 2892 0990
FAX : +852 2892 0770
Product specifications and descriptions in this document subject to change without notice. © 2009 JDS Uniphase Corporation
TEL : +49 7121 86 2222
FAX : +49 7121 86 1222
30162877 000 0809
August 2009
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