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Application Note

FTTx Access Networks and Services Quality Assurance and Testing Methodologies

Introduction

Increased competition from multiple system operators (MSOs), telcos, and Internet Protocol television (IPTV) service providers worldwide are driving the deployment of quadruple-play services over next-generation access networks. As a result, service providers are faced with many new business and service delivery challenges.

New Optical Access Networks Delivering Higher Bandwidths for Increased Service Offerings

Whether the access network is purely optical fiber-to-the home (FTTH) or based on a mixed fiber/copper technology (fiber-to-the curb [FTTC], fiber-to-the business [FTTB]), the requirements for operation and maintenance are changing dramatically compared to pure digital subscriber loop (DSL)-based access. At the same time, expectations have been set to reduce the maintenance effort especially on the fiber network, because it is regarded as more reliable than copper.

Lack of End–to-End Visibility

As service providers roll out more IP-based services (data and real-time), they must eventually decommission older time division multiplexed (TDM) network components and replace them with leaner and more cost-effective shared IP-based network architectures. During and after this transition, service providers will continually face two major challenges:

y IP services require a true end-to-end service view to competently perform quality of service (QoS) and quality of experience (QoE) test and assurance.

y Traditional service provider operations support system (OSS) infrastructures and organizations often lack the end-to-end service views necessary to assure their customers’ QoS/QoE for these new services.

Reducing Customer Churn

The ability to offer quadruple-play services in attractive bundled packages is only half the battle in reducing churn. Service providers must also deliver the best QoE to their customers. Those operators who can accomplish this and provide excellent customer care will retain and grow their customer base as well as position themselves to demand a premium in the market place.

2 FTTx Access Networks and Services Quality Assurance and Testing Methodologies

Creating Competitive Differentiation

The introduction of IP Multimedia Subsystem (IMS) for fixed mobile convergence (FMC) in itself is a major challenge as providers must ensure their existing network architectures, operational models, and service assurance tools can easily migrate to support this new paradigm. FMC will not only allow the delivery of simultaneous quadruple-play services on any device at any time, anywhere but will also give service providers the flexibility to offer new services and business models to customers much faster than before, creating competitive differentiation.

Reducing Operational Costs

In order to handle broadband growth for millions of subscribers, operational models must be optimized introducing efficient service management and operational processes across the network and converged services architecture.

It is evident, that having visibility to and measuring QoE is an essential part of a service provider’s competitive strategy for offering quadruple-play services. Providing a service assurance solution with the right mix of test and monitoring applications ensures the early detection and resolution of network, QoS, and QoE problems with limited or no customer impact. Such an effective service assurance solution must provide both proactive and reactive monitoring, as well as turn-up testing, troubleshooting, and fault isolation capabilities. Finally, all tools, network, and operational models must easily adapt to support new technologies and architectures such as FMC.

The Viavi Solutions Service Assurance Solution focuses on providing these capabilities to deliver a positive impact on dispatch reduction, customer service reactivity, operational expense savings, and improved efficiencies by:

y Managing the end-to-end service performance from ingress sources through the least reliable parts of the access network, such as various fiber infrastructures (FTTx and FTTH).

y Ensuring services are always available with the best possible QoS and QoE.

y Providing thorough end-to-end (content to customer) testing and monitoring with the right mix of probes, software, and OSS applications to truly inspire comprehensive, effective, and economical operations and processes ensuring superior customer service even during high subscriber growth phases.

y Providing a service assurance architecture that easily extends to address the future, such as requirements for FMC/IMS.

FTTX Technology

Passive Optical Network Technologies

A passive optical network (PON) is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters utilizing Brewster’s angle principles are used to enable a single optical fiber to serve multiple premises, typically 32 to 128. A PON consists of an optical line terminal (OLT) at the service provider’s central office (CO) and a number of optical network units (ONUs) near end users. A PON configuration reduces the amount of fiber and CO equipment required compared with point to point architectures.

Figure 1: PON Architecture

OLT

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1490 nm

Central OfficeServing up to 10,000 customers


The network equipment in the CO, or OLT, is connected via an optical splitter to the ONT installed at the customer’s premises. Because multiple customers share the optical fiber and OLT, PONs substantially reduce the investment required to serve a given number of customers. PON systems use 1310 nm wavelength for the upstream and 1490 nm wavelength for the downstream. Sometimes a 1550 nm wavelength broadcast video overlay is added. The International Telecommunications Union Standardization Sector (ITU-T) has created several standards for optical access systems based on the PON architecture, as shown in Figures 2 and 3:

y One of the first standards was Broadband PON (BPON). It uses Asynchronous Transfer Mode (ATM) cells for transmission and has a maximum access speed of 155 Mbps upstream and 622 Mbps downstream.

y The latest BPON standard suggests increasing the transmission capacity of 622 Mbps upstream and 1.2 Gbps downstream. However, the consensus is that the technical hurdle of achieving synchronization at speeds higher than 622 Mbps upstream is high given the BPON physical layer specification.

y Therefore, discussion of a new PON specification for gigabit-per-second-class transmission began in April 2001. Because the new optical access system is capable of gigabit-per-second transmission, it is called Gigabit PON (GPON), defined in ITU-T Recommendation G984.

y In 2004, The Institute of Electronic and Electrical Engineers (IEEE) defined the Ethernet PON (EPON), or 10 Gbps EPON (GEPON), standard as part of the Ethernet First Mile project. EPON uses standard 802.3 Ethernet frames with symmetric 1 Gbps upstream and downstream rates. EPON is designed for data-centric networks as well as full-service voice, data, and video networks. The IEEE Task Force P802.3av is currently designing the 10 Gbps EPON or 10GEPON.

Figure 3: NG PON Activity Roadmap (source Broadband Forum)

Figure 2: Standardization Organization for Optical Access


G.984.4, G-PON: ONT Management and Control Interface (OMCI) specification

ITU-T has created a standard management interface, called OMCI, between the OLT and ONU/ONT, enabling mixed-vendor networks, which is illustrated in Figure 4.

OMCI is the ONT Management and Control Interface. The OLT uses the OMCI to control an ONT. This protocol allows the OLT to:

y Establish and release connections across the ONT

y Manage the User to Network Interfaces (UNIs) at the ONT

y Request configuration information and performance statistics

y Autonomously inform the system operator of events such as link failures

The OMCI protocol is asymmetric: the controller in the OLT is the master, and the one in the ONT is the slave. A single OLT controller using multiple instances of the protocol over separate control channels may control multiple ONTs.

The ONT management and control interface requirements given in this recommendation are needed to manage the ONT in the following areas:

y Configuration management

y Fault management

y Performance management

y Security management

Note: ITU-T G.983.3 specifies BPON OMCI capabilities and ITU-T G.984.4 specifies GPON OMCI capabilities.

OLT

EMS

Network Topology

OLT/ONTManagement(TL1, SNMP)

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Figure 4: Example of OLT ONT Configuration and Management (source Broadband Forum TR-142)


Broadband Forum Technical Reports

The Broadband Forum defines technical reports (TRs) and working texts (WTs) that are related to home management. One of the key specifications defined by the Broadband Forum is TR-069. The auto configuration server (ACS) as defined by the Broadband Forum, or the Remote Management System (RMS) as defined by the Home Gateway Initiative (HGI), is TR-069 capable and provides a TR-069 interface and data model to remotely control and configure the remote gateway (RG) and other TR-069-enabled devices located in the home network (HN). Figure 5 provides an example of the TR-069 management architecture.

The Broadband Forum has defined a suite of TR-069-related standards for home management. The most important standards are shown in Figure 6.

Figure 5: TR-069 Management Architecture

Figure 6: Broadband Forum Main Standards for Broadband Access, Control, and Home

OSS/BSS Policy Call Center

IP STB

VoIP

Voice ATA

PC

ResidentialGateway (RG)

Storage

Auto-ConfigurationServer (ACS)

WT-131, WT-132:ACS Northbound Interface

NEW: TR-142TR-069 Framework for PON

TR-069 CPE WANManagement Protocol

TR-98 InternetGateway Device (IGD)

TR-111: NAT Traversal

TR-068, TR-124 RG HPNA G.hn WirelessMoCA Ethernet HomePlug

NEW: TR-135: STB

TR-104: VoIP

TR-122: Voice ATA

TR-140: Storage

TR-064, TR-133:LAN-Side CPE Management

TR-106: Common DataModel Template

NEW: TR-143Throughput

Performance Testing


The Broadband Forum TR-098 defines the RG object model. The major management functions it covers are:

y Device management

y QoS management

y Security management

y Configuration management

y Firmware upgrades management

y Performance monitoring

y Diagnostics and troubleshooting

y Local management application

Figure 7: Example of IP-based Services Configuration and Management with TR-069 for PON Access (source Broadband Forum TR-142)

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Subscriber Service

TR-142 describes how an ACS can remotely configure, troubleshoot, and manage a PON ONT with Layer 3 capabilities using TR-069, as shown in Figure 7.

Performance Management

As the Broadband Forum defines, the TR-069 management protocol provides support to allow the ACS to collect and monitor customer premises equipment (CPE) status and performance statistics. The TR-069 management protocol also defines a set of conditions under which a CPE should actively or passively notify the ACS of changes.


Diagnostics

The TR-069 management protocol provides CPE statistics collection via the ACS to support diagnostics, connectivity, or service issues. Figure 8 illustrates the TR-069 object models with statistics related to performance highlighted with a red rectangle. Diagnostic capabilities are highlighted with orange rectangles.

Figure 8: TR-098 Remote Gateway Data Model

The example in Figure 8 is for a DSL wide area network (WAN) device. The parameter sets for the WAN device change according to related standards for the applied access technology, as shown in Figure 9.

Figure 9: Broadband Access Standards for FTTx and xDSL

Internet Gateway Device

• Device Info• Vendor Config File

• Device Config

• Management Server

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• IP Ping Diagnostics

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• Total

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• WAN DSL Connection Management• Connection Service

• WAN DSL Diagnostics

• WAN Connection Device {i}• WAN DSL Link Config

• WAN ATM F5 Loopback Diagnostics

• WAN Ethernet Link Config

• WAN POTS Link Config

• WAN IP Connection {i}• Port Mapping

• Stats

• WAN PPP Connection {i}

• Port Mapping

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• Connection


• Total

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• Stats


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• Total, Showtime, Last Showtime, Current Day , Quarter Hour


• WAN DSL Connection Management

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• WEP Key

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LAN Device {i}


• IP Interface

Hosts

• Hosts


• Stats


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• WEP Key

• Pre Shared Key


• WEP Key

• Pre Shared Key

WLAN Configuration {i}

• Associated Device

• WEP Key

• Pre Shared Key


• Stats


• Stats


• Stats

Internet Gateway Device

• Device Info• Vendor Config File

• Device Config

• Management Server

• Time

• User Interface

• Layer3 Forwarding• Forwarding

• LAN Config Security

• IP Ping Diagnostics


• Connection


• Total

• Showtime

• Last Showtime

• Current Day

• Quarter Hour









• Stats


• Port Mapping

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• Connection


• Total

• Showtime

• Last Showtime

• Current Day

• Quarter Hour









• Stats


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WAN Device {i}






• Stats


• Port Mapping

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• WAN Common Interface Config• Connection


• Total, Showtime, Last Showtime, Current Day , Quarter Hour


• WAN DSL Connection Management

• Connection Service







• Stats


• Port Mapping

• Stats






• Stats


• Port Mapping

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Stats

Diagnostics

LAN Device {i}


• IP Interface

Hosts

• Hosts


• Stats


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• WEP Key

• Pre Shared Key


• WEP Key

• Pre Shared Key


• WEP Key

• Pre Shared Key


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• IP Interface

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• WEP Key

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• IP Interface

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• IP Interface

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• Stats


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LAN Device {i}


• IP Interface

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Management

RGTR-069

Network Service Providers

Broadband Access User

Application Service Providers

Video Headend

EthernetAggregation

GPONTR-156–GPON in the context of TR-101WT-167–GPON Fed DSLAMs

ADSL2PlusTR-100–ADSL2Plus Performance test planWT-105–ADSL2Plus Functionality test planTR-176–ADSL2Plus guidelines for IPTV

TR-101–Ethernet Access and AggregationTR-126–IPTV Quality of ExperienceTR-144–Multi-Service Architecture and Framework RequirementsWT-145–Next-Generation Access and Aggregation (TR-101bis)

Fiber-related Broadband Forum architecture specificationsTR-156 extends the IP Ethernet access aggregation in connection to a PON last mileWT-167 provided the common method for establishing fiber-fed DSLAMs

xDSL BondingTR-159–Management for xDSL Bonding

VDSL2WT-114–VDSL2 Performance test planWT-115–VDSL2 Functionality test plan


GPON Performance Management and Diagnostics

The Broadband Forum recommendation for GPON access consists of a combination of OMCI, defined by ITU-T Recommendation G984-4, for physical layer, and Ethernet layer management and TR-069 for higher layers (see Figure 10).

Figure 10: Broadband Forum Recommendation for GPON Management

Summary

An FTTx test and quality assurance solution must address the physical layer as well as Layer 2 and above to close the gap between subscriber QoE and root cause detection.

With Open Network Management System (ONMS) PON and Home PM solutions, operators can proactively detect customer QoE issues and rapidly determine whether a physical layer issue is causing the problem.


Physical Layer Test and Troubleshooting—ONMS PON

Testing PONs with Optical Time Domain Reflectometers

The OMCI specification determines the status of the ONT and the physical media dependent (PMD) layer. OMCI requires communications between the OLT and the ONT. When the ONT does not respond, either due to a fault or because it is not installed or commissioned yet, it is impossible to determine if the problem originates in the ONT or the PMD, which explains why many operators require an external test system that can test the PMD when the ONT is unreachable.

An optical time domain reflectometer (OTDR) can pinpoint the location of faults in a fiber link and certify the workmanship involved in an installation. OTDRs find and characterize both reflective and non-reflective events in optical fiber runs by sending laser pulses of different widths, see Figure 11.

Figure 11: Basic PON Structure

OTDR performance is measured using these two main parameters:

y The dynamic range (DR) determines the length of fiber link the OTDR can test (higher values enable testing longer links)

y The event dead zone (EDZ) is the minimum distance of separation between two different optical reflective events that the OTDR can resolve (shorter values enable resolving more closely spaced events)

The DR and EDZ both increase with longer pulse widths. Tuning the OTDR requires a tradeoff between the DR and EDZ.

ONT

Distance (km)

Atte

nuat

ion

(dB)

The OTDR displays the detailed ‘Map’ of the tested fiber link

ConnectorPair

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FusionSplice

MechanicalSplice

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Fiber�n d


Distinguishing between the different segments of a PON can be challenging. Figure 12 shows the OTDR trace for a simple 1x2 splitter when only one segment is connected. If the second segment is connected, the contributions of both segments appear on the trace, as Figure 13 shows. The different lengths enable identification of the two segments. If each segment were the same length, the OTDR trace would appear similar to that shown in Figure 14.

1x2OTDR

ReflectiveTermination

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Figure 12: OTDR Trace from a 1x2 Splitter with Only One Segment Connected

Figure 13: OTDR Trace from a 1x2 Splitter with Segments of Different Lengths


Several factors complicate testing with an OTDR:

y Distances between the splitter and the different ONTs usually are nearly equal, because customer residences are typically located at about equal distances from the splitter.

y Distances between the splitter and the ONT can be as short as a few meters.

y Split ratios are not typically 1x2 but rather 1x16, 1x32, or 1x64, increasing the splitter loss. The typical loss of a 1x64 splitter is 20 dB.

Figure 15 shows an OTDR measurement from a 1x32 PON.

1x2OTDR



L1

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L1 = L2

1.5 dB

Splitter Loss

L1 Length of Segment 1L2 Length of Segment 2

Distance (m)

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Figure 14: OTDR Trace from a 1x2 Splitter with Only Segments of Equal Length

Segment Ends

Zoom

Figure 15: OTDR Measurement on 1x32 PON


The ideal PON OTDR would have a very high DR, so it could detect optical events on the fiber branches beyond the splitter and a very short dead zone to differentiate between terminations which usually are not reflective. Resulting from the tradeoff mentioned earlier, OTDRs do not have both high dynamic ranges and short dead zones, making it necessary to add a reflective optical element at each ONT. An OTDR can distinguish this element from noise using a very short pulse width, as Figure 16 shows. Perform troubleshooting while the PON is in service, because the OTDR must use a wavelength different from the one the traffic uses. The latest ITU-T G984.4 Recommendation allocates the bandwidth for the test between 1625 and 1670 nm. Insert the test wavelength by adding a wavelength division multiplexer (WDM) at the near end. ITU-T Recommendation G984.5 states that the ONT must not be sensitive to the test wavelengths.

Figure 16: OTDR Trace on PON Equipped with Reflective Filters

An Automated Approach to OTDR Testing

Test multiple PONs with the same OTDR using an optical switch to select the PON to be tested, as Figure 17 shows. This approach enables a single OTDR to handle testing for an entire site.

Figure 17: PON Test System Integrating a Switch

Splitter Loss

Reflective Terminations

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OTDR1625 nm


Remotely operate the optical switch by configuring it to be controlled from an application, which provides these additional benefits:

y Access the PON test system from a remote location through a Web browser or mobile phone

y Record the network signature at different stages such as during network construction, provisioning, and troubleshooting

y A single person can test the network during installation

y Quickly and easily distinguish problems between the equipment and the fiber

Figure 18 shows how to use the system for provisioning. Technicians can log into the application from their mobile phone. After registering the customer ID, technicians enter the optical power measured at the customer connector, which triggers an OTDR measurement. The system automatically recognizes the new peak and records its position and level.

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PON Test System

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Reference Table

Customer ID Power Peak Distance Peak Level123456 –20 dBm 3540 m 4.0 dB123457 –19 dBm 3647 m 4.8 dB

Figure 18: PON Test System used for Provisioning


Figure 19 shows how to use the PON test system for troubleshooting. An operator receives an alarm from the ONT or a call from a customer. Using the PON test system, the operator can immediately check if the fiber is okay. The operator initiates an OTDR measurement on the suspected PON and the result is compared with the records to determine changes in the customer’s fiber attenuation. The disappearance of the peak typically indicates that a fiber cut or additional attenuation is the cause of the problem.

Figure 19: PON Test System used for Troubleshooting

Customer ID Power Peak Distance Peak Level123456 –20 dBm 3540 m 4.0 dB123457 –19 dBm 3647 m 4.8 dB

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PON Test System

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OLT EMS


Network and Service Test and Performance Monitoring— Home Performance Management (PM)

Home PM Features

As soon as a basic connection exists between the OLT and the ONT/ONU, an exhaustive set of performance monitoring data is available for retrieval from the OLT (OMCI data) and the ACS (TR-069, TR-098, TR-104, TR-135, TR-196n PD-181 later on) data to evaluate all aspects of service quality and QoE for Internet, voice, video, and Femtocell services.

As previously discussed, QoS and QoE visibility at the customer premises is essential to ensure successful delivery and management of IP and real-time IP services. The Viavi Home PM solution was designed to provide this customer premises (QoS/QoE) visibility. Viavi developed Home PM to cover the CPE domains (both residential and enterprise) extending the service providers QoS/QoE visibility, which is achieved using data from OLTs, CPEs, and network devices that support TR-069.

Leveraging the TR-069 and OMCI standards enables Home PM to further alleviate interoperability issues between service concentrators.

Key features of Home PM:

y Provides a comprehensive solution for multi-vendor CPE management: monitoring, diagnosis, and troubleshooting, which compliments existing zero-touch provisioning, configuration update, and software upgrade solutions.

y Provides the means to measure service availability and customer experience in real-time and over longer periods of time to quickly pinpoint which service or part of the network might be contributing to service downtime/issues.

y Provides the added value of pre-packaged rules for root-cause analysis based on access technology and multi-play services.

– These packaged rules provide accurate and clear fault and dispatch statements, shown in Figure 20.

– These packaged rules reduce the number of events that require attention and cut first-level diagnosis lead times enabling Network Operations Center (NOC) and customer support teams to become more efficient, pruning operational expenses.

Figure 20: Example Home PM Dispatch Statement


y A true end-to-end service assurance solution based on a carrier-class architecture that performs proactive monitoring and end-to-end tests from the home through the access, aggregation, edge, and transport networks up to the headend to accurately detect and localize faults.

y A multi-vendor network and service management solution designed for rapid deployment.

y A scalable, flexible, centralized, web-based solution that is easy to deploy.

y A solution that can perform “in-service” assurance—monitors, tests, analyzes, and reports all the above without interrupting the customer’s service.

The Home PM solution is used throughout the life cycle of quadruple-play services, by:

y Performing continuous multi-play proactive performance service-level monitoring

y Automating the proactive collection of quality metrics from the ONT, RG, analog terminal adaptor (ATA), and set top box (STB)

y Performing advanced alarm correlation and root-cause analysis

y Outputting results in an easy-to-use, intuitive dash-board front end

y Performing on-demand real-time measurement on any ONT, RG, ATA, and STB to verify the current functioning level

y Providing notification of events/alarms through its north bound interface (NBI)

Home PM Virtual Probe

Home PM includes a virtual probe concept, as illustrated in Figure 21, that allows daily proactive monitoring of each perceived customer experience and automatically polls customers that are experiencing poor QoS on a more frequent basis.

Figure 21: Home PM Virtual Probe Concept

Home PM

ACSACS

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By performing neighborhood and single end-user analysis, Home PM virtual probes help to automatically identify fiber and copper cabling issues or network problems such as:

y Pseudo-real-time exchanges or COs that are no longer delivering the expected services to the end-users (Figure 22).

Figure 22: Critical Exchange Dashboard

y Physical layer PON problems behind the splitter identified by detecting similar problems for all customers connected to the same fiber.

y Aggregation or transport problems identified by detecting similar problems for all customers in the same location (CO, city, or region)

y Identification of OLTs and/or Digital Subscriber Line Access Multiplexers (DSLAMs) that are providing the worst QoE to the end users.

y Faulty OLT boards identified by associating problems on customers that are connected to the same OLT.

y Fiber degradation issues due to bending or a dirty connector detected as changes of the transmitted/received optical power between OLT and ONT (from OMCI statistics) as well as transmission errors on Layer 2 (packets dropped, errored packets).

y Crosstalk and interferers on the copper part of the access line (FTTB/C) detected by analyzing the power spectrum density plots gathered through dual-ended line testing (DELT). Standards bodies have adopted this testing measure under the ITU-T ADSL2 or G.992.3 numbering scheme.

y Copper and in-house cabling issues caused as a result of line errors and line burst errors (errored received and errored sent on every LAN port and media, such as USB, Ethernet, WLAN, Power Line Technology, and HPNA).

y Insufficient transmission control protocol (TCP/IP) throughput (TR-143).

y Home network issue when good measurements show acceptable WAN statistics, but errors are detected on the local area network (LAN).


y Incorrect home device configuration shown after comparing the current configuration with the expected configuration for service delivered, as Figure 23 shows.

Figure 23: Home Device Status

y QoE issues identified by monitoring new customers to avoid churn, as Figure 24 shows.

Figure 24: Home PM—New Customers’ Dashboard


Figure 25 shows an example of the overall measured quality for all subscribers. Global quality is reported for the WAN and LAN interfaces as well as for IPTV service.

Figure 25: Overall Service View

Viavi Value PropositionThe Viavi ONMS/Home PM bundle, as shown in Figure 26, provides the service provider with FTTx access and home/customer premises QoS and QoE visibility for IP and real-time IP services reducing operational costs and increasing customer satisfaction.

Figure 26: Viavi Solution for FTTH Test and Monitoring

ACS

EMS

ReferenceData

Customer IDOLT IDFiber ID

STB

VoIP

PC

RG TV

Home PM

ONMS Topaz

Home PM

Voice

Internet

Video

1490 nm

1310 nm

1625/1650 nm

OLT

OMCI

TR-069

Splitter

GPON

Splitter

ONT

© 2015 Viavi Solutions, Inc. Product specifications and descriptions in this document are subject to change without notice. homepmfttx-an-sas-tm.ae 30162984 901 0611

Contact Us +1 844 GO VIAVI (+1 844 468 4284)

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This solution bundle reduces operating costs by:

y Covering all phases of network life cycle from installation, commissioning, provisioning, to service delivery, operation, maintenance, repair, service assurance, and customer care.

y Covering all technologies related to the access network—physical, logical, and service layers (including quadruple-play services).

y Reducing the number of calls to the help desk through proactive monitoring

y Reducing the call handling times by providing the visibility into the home to the help desk

y Reducing the cost per fault by:

– Improving dispatch accuracy through reduced truck rolls (dispatch to fix versus to find) and reducing unnecessary visits (dispatch the right person to the right place with the right tools—the first time)

– Reducing the need for handheld testers

– Reducing fault volumes and rates (fewer trouble tickets and dispatches)

y Optimizing process flows by:

– Controlling the process from the customer care center

– Improving the provisioning process

– Improving quality and accuracy of test and diagnostics

– Protecting current revenues and growing new business

– Limiting customer care center growth

Improve customer satisfaction and the end user experience by:

y Proactively detecting quality degradation and faults

y Supporting both residential and enterprise customers

y Supporting customer care in the handling of customer complaints

y Improving the speed of repair, reducing mean time to identify/repair (MTTI/R)

y Reducing time required to clear faults

http://www.viavisolutions.com/contacts

http://www.viavisolutions.com

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