Leveraging Broadband Access Infrastructure. Backhaul Application Note

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Leveraging

BroadBand access

infrastructure

for iP/MPLs

BackhauL

ApplicAtion note

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aBstract

Service providers are facing a highly competitive environment in an era of unrelenting subscriber traffic growth. Business service connectivity requires delivery at the most economical cost points possible. The need for high-quality, high-bandwidth backhaul options is leading service providers to look for a range of cost-effective access transport alternatives. Ubiquitous residential broadband access and triple play networks, where last-mile end-user connectivity is provided through either Digital Subscriber Link (DSL) or Gigabit Passive Optical Networks (GPON), can provide such cost-effective access technologies for mobile backhaul (MBH) and business services delivery. Leveraging these networks for mobile backhaul and business services can provide a scalable and cost-effective solution set with high reliability and availability, and additionally provide a means of smoothly transitioning to converged packet transport using IP/MPLS. This application note describes a comprehensive, integrated set of DSL and GPON backhaul capabilities built on Alcatel-Lucent products. These capabilities are intended to complement leased lines with DSL connections, or replace them completely using either DSL or GPON. It is possible to provide Ethernet connectivity using either DSL or GPON as an uplink. The economic benefit for operators and service providers is clear, as unbundled copper loops are often an order of magnitude cheaper than leased lines, the cost of DSL equipment has dropped as a result of continuous innovation, and a GPON deployment has clear cost savings as opposed to a conventional point-to-point fiber deployment.

It is becoming increasingly apparent that operators must work to leverage all available assets to accommodate growing traffic cost-effectively — across fiber, microwave and also a broadband infrastructure. This application note illustrates a solution that contains differentiated products and allows the promotion of business services and mobile backhaul transport via broadband access from a niche capability to a long-term, highly viable infrastructure for backhaul.

introduction

Modern wireless standards support peak download rates of many Mbit/s, thus leading to significant increases in traffic volumes. However, the revenue per bit that operators can expect to extract from data services is significantly less than that for voice services. For business services, T1/E1, ATM and Frame Relay continue to generate significant operator revenue — with Ethernet Layer 2 and Layer 3 VPN services having increasing importance. Preserving this revenue base is essential. However, transitioning the delivery of those services to a common IP/MPLS-based infrastructure serves to collapse an underlying legacy network overlay, realize operational savings, and reduce network complexity.

Making use of broadband access for MBH and business services is not only about overcoming the lack of fiber availability, but it is also about overcoming the lack of ubiquitous high-bandwidth solutions. Alcatel-Lucent has cost-effective solutions to address both of these needs.

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A High Leverage Network™ architecture addresses the key challenge of how to

simultaneously provide efficient low-cost transport and innovative, revenue generating, value-added services. For broadband backhaul, it enables continuously scalable high bandwidth from the access layer with the lowest Total Cost of Ownership (TCO) in order to address business services and MBH needs, leveraging xDSL, GPON and P2P fiber. At the same time, making use of IP/MPLS for backhaul allows for distinct end-to-end advantages that not only differentiate service offerings, but offer distinct operational advantages when compared to a purely Ethernet-centric approach.

Fixed broadband access solutions have been deployed to deliver high-speed Internet access, (high-definition) video and (lifeline) voice services to users around the world – all while supporting business services such as TDM, Ethernet and VPNs. The stringent requirements that these services place on the access network greatly overlap with those for mobile backhaul and broadband business services. Thus, in the course of pursuing their own broadband services business models, wireline service providers have actually been deploying a broadband backhaul-ready infrastructure with the requisite QoS and multiservice transport capabilities. With the necessary broadband infrastructure already deployed and therefore making use of GPON, xDSL or P2P fiber, the required missing component has been an aggregation and routing device, combined with an ONT and a high-bandwidth DSL uplink, as part of a complete solution that can fully utilize this infrastructure for maximum effect.

soMe tyPicaL soLution

dePLoyMent scenarios

The 7705 SAR-M enables an extensive set of broadband backhaul capabilities. Broadband backhaul on the 7705 SAR-M is based on a series of three modules (see Figure 1),

supported on fan-cooled variants of the 7705 SAR-M that can make use of ADSL2, ADSL2+, SHDSL, VDSL2 or GPON uplinks. As such, the 7705 SAR-M specifically has the ability to migrate from copper access to fiber access uplinks within a single platform where that path may go from T1/E1 to Ethernet point-to-point fiber or from DSL to GPON, or any combination to fit an operator’s needs. See appendix A for more detail on the technical specifications of the 7705 SAR-M.

Figure 1. The 7705 SAR-M, xDSL, GPON and DCM Modules

7705 SAR-M

xDSL

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The Alcatel-Lucent 7705 SAR-M is only one component of a broadband backhaul solution that makes use of end-to-end IP/MPLS networking. Alcatel-Lucent’s IP access portfolio builds on the Intelligent Services Access Manager (ISAM) family. The Alcatel-Lucent ISAM converged access platform portfolio offers a high-density, premium technology for broadband services to the most demanding operators. Stringent backhaul capabilities require an end-to-end solution that scales well, excels in availability, troubleshooting and monitoring tools, and offers advanced Service Level Agreements (SLAs). The ISAM delivers on all of these capabilities while providing a flexible mix of future-proof access technologies such as xDSL, GPON and point-to-point fiber. A diverse product offering also complements these capabilities with a needs-specific portfolio that includes the following Alcatel-Lucent products: the 7360 ISAM FX Shelf, the 7342 ISAM FTTU, the 7302 ISAM and the 7330 ISAM FTTN.

Within the context of broadband infrastructure, there are two typical scenarios employing GPON or DSL infrastructure: the hybrid off-load scenario and the pure backhaul scenario.

hybrid off-load scenario

For mobile backhaul, leased lines have historically been used to connect to the base station to carry TDM voice, signaling, synchronization and data traffic. With the drastic increase in HSPA subscribers, continuing the use of leased lines is an expensive proposition. With the HSPA off-load scenario, voice and mission-critical traffic (e.g., node management, signaling) remain on the leased-line infrastructure while data traffic is moved to the cost-optimal DSL network, thus decoupling cost from capacity.

Note that with the DSL combination module in the 7705 SAR-M (see Appendix A), the deployment can equally leverage DSL for both voice and signaling, thereby making use of SHDSL and data off-load via ADSL2+ or VDSL2. By using DSL for both voice and signaling. as well as data off-load, this deployment option further decouples backhaul costs from expensive leased-line charges.

Figure 2. HSPA off-load scenario

7705 SAR-M T1/E1 T1/E1 MPLS or GRE tunnel xDSL ATM ATM ISAM 7450 ESS PACKET NETWORK 7450 ESS 7750 SR BSC/RNC SONET/SDH OR ATM

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Pure broadband backhaul scenario

In the scenario using backhaul via a pure broadband infrastructure, a cost-optimal DSL or GPON network access link is used to aggregate all traffic to a DSLAM or OLT as illustrated in Figure 2. This option maximizes savings, as leased lines can be completely decommissioned in this deployment case. It is equally applicable for cost-effective business services, including L2 VPN, L3 VPN, T1/E1 CES, ATM, HDLC or Frame Relay, thus making use of GPON or DSL for backhaul.

Figure 3. Pure backhaul via DSL or GPON

7705 SAR-M MPLS or GRE tunnel xDSL or GPON ISAM 7450 ESS PACKET NETWORK 7450 ESS 7750 SR 7705 SAR-M BSC/RNC

requireMents for BroadBand

infrastructure BackhauL

In order to properly address broadband infrastructure backhaul while leveraging GPON or DSL, there are a number of specific requirements that need to be addressed by the selected solution.

requireMents Benefits

comprehensive services

offering legacy network interfaces (tDM, Frame Relay, AtM) are often primary revenue generators, and their interfaces need to be maintained while providing options to support ethernet- based VplS, VpRn and ethernet pseudowire services High reliability and

availability

Matching performance standards set in tDM networks improves customer experience, thus reducing churn and improving customer loyalty

efficient bandwidth

scalability optimizing capital and operation expense with a cost-effective, modular evolutionary platform that grows with end-user needs and provides the required bandwidth to satisfy service requirements

converged packet transport using ip/MplS

consolidating services over a common technology and infrastructure allows for the migration of tDM voice and data services to a common ip packet architecture Quality of Service Maintaining differentiation and control of service priority within the network to

deliver tiered tariff data and voice services to meet commercial requirements of service providers

network timing and synchronization

Supporting accurate timing distribution to access devices for synchronization or as a service to the end customer

Strong network management and oAM capabilities

Delivering the operational service and network layer visibility to ensure the commercial expectations of the mobile data explosion are met while managing opeX, ultimately in an end-to-end, all-ip network

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comprehensive services offering

It is essential to provide modern Ethernet-based services. Concurrently, when dealing with legacy networks, it is important to address multiservice aspects effectively. Many businesses may have a significant installed base of customer equipment that use technologies such as Frame Relay, ATM or TDM. A CPE refresh may be considered a contract violation or simply a painful procedure due to cost. This means the device which is located in the central office needs to understand and, in some cases, manipulate the traffic arriving from the customer premise to be carried on the transformed network. Services are the cornerstone of any modern network. Having the ability to provide point-to-point Layer 2 pseudowires (Ethernet/TDM/ATM/FR), Layer 2 VPN or Layer 3 VPN services simultaneously between various provider edge (PE) nodes is a key to a successful solution.

The ability to interconnect services as appropriate is also important. In some topologies, it may be required to create pseudowire Emulation (PWE) spokes for remote Ethernet access circuits that are connected to a Virtual Private LAN Service (VPLS) at a central site — or provide multiple VPLS services remotely which are interconnected to a Virtual Private Routed Network (VPRN) for Layer 2 pre-aggregation of routed services. This flexibility allows for the ability to creatively use services to solve customer deployment problems.

high reliability and availability

High reliability and availability are required in a number of different aspects:

• IP/MPLS Layer: With high reliability and resiliency to match the standards set by TDM switching technology, IP/MPLS allows mobile aggregation to scale in a controlled and managed way, while delivering guaranteed per-service QoS, full-traffic isolation and security in the form of VPNs. The solution brings a strong suite of traffic engineering and resiliency capabilities via functions such as Fast Reroute (FRR), primary and secondary LSPs, and redundant pseudowires.

• DSL Physical Layer: At the physical layer within DSL access networks, multi-pair bonding across SHDSL, VDSL2 or ADSL2+ bonded lines deliver such high-availability. Multi-pair bonding ensures that, in the event of a failure on one individual line, the aggregate bonded group remains operational. Additionally, SHDSL in combination with an ADSL2+/VDSL2 interface allows for broadband uplink redundancy whereby data traffic may be re-routed over the alternate DSL uplink.

• GPON Physical Layer: Within a GPON network, physical uplink redundancy is achieved, if required, through the use of PON feeder redundancy (Type “B”) at the OLT, providing an alternate diversely-routed PON path in the event of a fiber cut or port failure.

• Platform hardening: Uplink reliability and availability cannot satisfy operator needs alone unless the underlying platform delivering these capabilities is environmentally hardened. Backhaul locations will not necessarily be located in controlled

environments and, thus, temperature hardening must include not only the demark aggregation platform itself, but additionally all the modules that support uplinks to the access network (integrated DSL interfaces and integrated GPON interfaces alike).

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efficient bandwidth scalability

GPON optical line terminals (OLTs) and DSLAMs are cost-optimized aggregation platforms; they have the ability to concentrate traffic from many sites and groom that traffic to minimize port consumption in switches and routers.

The GPON Physical Layer is already cost-optimized for downstream/upstream bandwidth asymmetry. With multi-pair ADSL2+/VDSL2 bonding, this same bandwidth asymmetry is equally preserved, whereas SHDSL delivers symmetrical data services. With the availability of vectoring for VDSL2, bandwidth gains over copper will continue to be realized with Alcatel-Lucent continuing to lead the market in terms of innovation. Note that despite the underlying asymmetry for GPON and VDSL2, either technology can still be used to easily deliver symmetrical data services.

The need to deliver higher bandwidths to service subscribers is becoming increasingly critical for business subscribers and mobile backhaul alike. Figure 4 illustrates the current view on bandwidth requirements for MBH. An edge aggregation CPE/ONT must not only meet these needs but the platform must additionally exceed them in order to meet an operator’s long-term requirements for broadband infrastructure backhaul. A platform evolution from DSL to GPON must also be considered, as once DSL is deployed as a backhaul transport technology, the same economics and business case driving the use of DSL should be equally considered for GPON.

For business services, offering alternatives where copper can be competitive with cable and fiber is essential as it provides incumbents with the ability to continue to leverage existing assets and avoid the costly capital works associated with trenching fiber. Physical integration of a DSL modem and ONT functions into an edge aggregator, the 7705 SAR-M, leads to further cost efficiencies in terms of rack space and general equipment management.

Figure 4. Mobile backhaul capacity requirements

500 DO WNS TREAM BAND WID TH (MB/S) 400 300 200 100 High-end wholesale CELL SITE REQUIREMENTS

Average, 1 operator 1-pair VDSL2 @ 1000 M 2-pair bonding 8-pair bonding + vectoring Phantom mode 8-PAIR BONDING

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converged packet transport with iP/MPLs

When planning to leverage a residential DSL or GPON infrastructure, additional operational cost savings can be achieved through the convergence of multiple overlay networks in the terrestrial backhaul infrastructure. This provides the capability to transport and manage TDM-based and packet-based services on a single IP Carrier Ethernet packet-based network. A solution based on a multiservice routing and switching platform can accommodate legacy access needs and be optimized for a carrier-grade Ethernet-centric evolution. TDM, ATM/IMA, Frame Relay and HDLC can be adapted via the use

of IP/MPLS-based pseudowire transport where their use brings mature and efficient utility to an operator’s network.

While pseudowires can be carried over a number of packet or frame-based

infrastructures, the use of MPLS has strong attributes particularly for this application. As a convergence technology, MPLS brings advantages in the following areas:

• Physical Layer independence: MPLS runs on any physical media; PDH, SDH, Ethernet, broadband or microwave

• MPLS is topology agnostic: It runs in linear topologies, rings, meshed environments, point-to-multipoint environments, etc.

• MPLS has a powerful suite of OAM functionality that can be leveraged end-to-end • MPLS provides a range of protection schemes to meet the end-to-end operational

requirements independently from the physical layers

The physical layer independence of MPLS makes it an ideal fit for DSL- and GPON-based business services and for mobile backhaul. While pseudowires provide an excellent vehicle for adapting legacy and current access requirements into the RAN, delivering native Ethernet-sourced IP traffic will continue to gain strategic importance. Ethernet pseudowires can be used to satisfy this requirement as part of a highly converged Carrier Ethernet-centric solution.

quality of service

For business services, being able to provide a managed service with strict SLAs is a significant differentiator for offering a premium service offering.

For mobile backhaul, 2G and 2.5G services have traditionally been transported based on TDM circuit emulation, whereas for 3G, transport is primarily based upon ATM/IMA with vendors increasingly introducing Ethernet as a connectivity option. As base stations evolve, including those supporting LTE/4G, Ethernet media and any-to-any switching and routing will become common. For each service, QoS can be operationalized based upon the parameters defined for that connection. Within 2G/2.5G backhaul, for example, CES service pseudowires are mapped to the highest priority. For 3G, VCI/VPI or QoS parameters can be used to define priority. As base stations evolve to Ethernet, 802.1p and 802.1q or DSCP bits can be used to identify the desired priority for specific traffic streams.

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When multiple services are aggregated from a customer, traffic classification, buffering and scheduling must be provided for each given service. For example, in MBH, voice traffic has very stringent latency and jitter requirements which translate to a high-priority service with minimal queuing. High-priority data may also require prioritized scheduling but may be less sensitive to delay and more sensitive to data loss — this requires a high-priority classification with deep-queuing capabilities. In the event of congestion, the system must manage traffic flows to guarantee that lower traffic priorities are discarded before higher priorities. When interfacing to the packet network on egress, traffic shaping and marking must be applied to ensure downstream devices can make appropriate packet decisions.

The 7705 SAR provides comprehensive hierarchical traffic conditioning and management functionality for controlling network QoS while maintaining strict SLA enforcement. Alcatel-Lucent DSL and GPON solutions have been deployed widely to deliver triple play services around the globe, delivering high-speed Internet access, high-definition video and lifeline voice services. These services have stringent requirements for bandwidth, QoS and convergence — requirements that are parallel to those of premium business services and mobile backhaul.

network timing and synchronization

Circuit emulation services and mobile backhaul applications require accurate clock recovery. In the case of mobile backhaul, cell site equipment requires an accurate clock, for example, to set its radio frequencies and to correctly execute call hand-offs. Cellular

radio systems require frequency synchronization of ±50 ppb1_.

When frequency synchronization needs to be delivered via the backhaul network, making use of physical layer clock recovery via the broadband aggregation network provides a highly accurate option.

GPON Physical Layer Synchronization

ITU-T G.984.3 defines the transport of a stable clock from the GPON OLT at the central office to the GPON ONT (with the cell site gateway). This physical layer clock provides a reliable, deterministic frequency synchronization source. The cell site gateway (7705 SAR-M) can then slave an E1/T1 or synchronous Ethernet interface to this clock, thereby providing the required synchronization to the base station.

DSL Network Timing Recovery (NTR) synchronization

For a DSL network, NTR as defined according to ITU-T G.993.2 for VDSL2, ITU-T G.992.5 and ITU-T G.991.2 for SHDSL can be used as a source of timing. Again the cell site gateway (7705 SAR-M) can slave an E1/T1 or synchronous Ethernet interface to the clock, passing synchronization to the base station.

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IEEE 1588v2 Precision Time Protocol (PTP) synchronization

An IEEE 1588v2 PTP slave can be utilized at the cell site gateway for frequency synchronization. The PDV characteristics of GPON and of DSL in some deployments may be such that achieving synchronization over them with the transparent use of 1588v2 could be challenging depending on the overall network topology. Therefore, the preferred method of frequency synchronization in these cases is often achieved with the use of a physical layer clock. Advances in 1588v2 capabilities (such as on- path support and the delivery of time and phase) make this technology an important option in synchronization distribution planning.

The 7705 SAR product line natively supports a strong, flexible range of synchronization capabilities. A summary of the supported physical layer timing options via broadband backhaul are outlined in Figure 5. In all cases, clock recovery via the broadband backhaul network can be used as reference timing for T1/E1 interfaces, SyncE, sync out, 1588 via master clock functions, or Differential Clock Recovery (DCR) in order to provide up to 16 different timing domain references.

Figure 5. Supported synchronization options for the 7705 SAR-M

7705 SAR-M TIMING LAYER Eth, T1/E1 Eth, T1/E1 ADSL2+, SHDSL, VDSL2 ISAM PACKET NETWORK 7750 SR PRC BSC/RNC 7705 SAR-M GPON ISAM PACKET NETWORK 7750 SR BSC/RNC PRC DSL NTR GPON PHY E1 PHY, Synch E

strong network management and oaM capabilities

The 5620 Service Aware Manager (SAM) is the overarching management entity for end-to-end wireless domain management. The 5620 SAM provides comprehensive support for Fault, Configuration, Accounting, Performance and Security (FCAPS). The 5620 SAM application suite is a tightly-integrated management system that enables provisioning of an end-to-end service using wizards or point-and-click configuration from a single application (Service Manager) without having to individually configure each device in the connection path. The 5620 SAM greatly reduces the complexity and risk typically found in provisioning complex services using today’s edge routers. When deployed for mobile backhaul, best-of-breed broadband management domains remain intact ensuring that any subscriber management required on the ISAM is maintained, whereas end-to-end service provisioning for mobile backhaul remains within the domain of the 5620 SAM.

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Maintaining SLA guarantees with the 5620 SAM in conjunction with the 7705 SAR is a key strength of an end-to-end Alcatel-Lucent solution, as the 5620 Service Assurance Agent (SAA) can be used to minimize operator workload by proactively probing delay, jitter and loss that each service experiences periodically. Additionally, Automatic Discovery and Provisioning (ADP) is supported on all Ethernet interfaces on the 7705 SAR as well as on GPON and DSL interfaces. When mobile operators are faced with deploying potentially thousands of 7705 SARs, automated bring-up and template provisioning capabilities are essential. ADP on the 7705 SAR provides exactly this capability, greatly reducing the workload required to commission new systems.

concLusion

The use of broadband networks for backhaul transport can prove a cost-effective option for a service provider, as this method of backhaul leverages in-ground copper or an existing fiber deployment, and serves to monetize an access infrastructure investment, thereby resulting in an expedited return on investment. Successful operators will leverage all available assets to accommodate growing traffic cost-effectively — across fiber, microwave and also the broadband infrastructure.

The approach presented supports an evolution strategy that provides a scalable solution with the ability to evolve from copper (T1/E1/DSL) to fiber (P2P, GPON or Gigabit Ethernet) within a single platform without requiring a costly, labour-intensive upgrade. To be a viable solution for broadband backhaul, the broadband access solution must: • Supply a comprehensive services offering including support for managed Ethernet

services as well as legacy services (TDM, ATM, Frame Relay and HDLC) • Deliver redundancy and resiliency at the platform and network levels

• Cost-effectively deliver hundreds of Mb/s of backhaul bandwidth from a business/ cell site

• Natively integrate a variety of broadband technologies including xDSL and GPON uplinks

• Support flexible QoS assignment and protection for multiple differentiated traffic flows • Provide the required synchronization solutions

• Provide a scalable end-to-end management solution that can deliver the required operational management capabilities required to address the service and commercial expectations in an end-to-end IP network

Until now, no broadband access solution supported all of these characteristics, preventing broadband access from being seriously considered for long-term mobile backhaul. The Alcatel-Lucent solution based on the 7705 SAR-M and ISAM changes this situation and permits operators to further leverage the value of their network investments.

This solution successfully addresses the needs of business service operators that are looking to maximally leverage existing copper assets in order to remain competitive

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For mobile backhaul, the use of broadband infrastructure can support a long-term solution for LTE backhaul. In particular, while GPON was already well positioned from a bandwidth and synchronization point of view, copper backhaul has suffered from deficiencies in those areas that relegated it to stop-gap solution status. The combination of the Alcatel-Lucent ISAM and the 7705 SAR-M brings powerful new innovations to position operators for success in backhauling services across broadband infrastructures.

aPPendix a: BroadBand

BackhauL soLution coMPonents

The Alcatel-Lucent 7705 SAR-M (Figure 6) complements the existing family of 7705 SAR products with capabilities to natively leverage broadband backhaul. One rack unit (RU) high and supporting a hot-swappable module slot, the platform delivers a combination of compact size, temperature hardening and architectural flexibility.

The 7705 SAR-M is orderable in four different configurations. All four variants of the SAR-M support four 10/100/1000 Base-TX with small form factor pluggable optics (SFP) plus three 10/100/1000 Base-T auto-sensing Ethernet ports. The variable capabilities of the four variants are:

• Fan cooled with a module slot

• Fan cooled with a module slot, plus 16 T1/E1 any service any port (ASAP) ports • Passively cooled

• Passively cooled, plus16 T1/E1 any service any port (ASAP) ports

Figure 6. The 7705 SAR-M, xDSL, GPON and DCM Modules

7705 SAR-M

xDSL

GPON DCM

Broadband backhaul on the 7705 SAR-M is based on a series of three modules, supported on fan-cooled variants of the 7705 SAR-M, that can make use of ADSL2, ADSL2+, SHDSL, VDSL2 or GPON uplinks. As such, the 7705 SAR-M specifically has the ability to migrate from copper access to fiber access uplinks within a single platform where that path may go from T1/E1 to Ethernet point-to-point fiber or from DSL to GPON, or any combination to fit operator needs. This migration capability provides great architectural flexibility for a service provider, as the platform supports — from day one — a long-term modular vision for backhaul as well as the capability to grow and evolve along with the access network. The ability to provide a common set of features across a number of different access technologies also enhances the applicability of the platform to provide backhaul via the most cost-effective means available.

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Table 1 provides details on the supported broadband plug-in modules for the 7705 SAR-M and their principal attributes.

table 1. comparison of broadband plug-in modules for the 7705 sar-M

xdsL ModuLe gPon ModuLe

dsL coMBination (“coMBo”) ModuLe (dcM)

• 8 RJ-11 connectors • 8-pair ptM bonding over

ADSl2, ADSl2+ or VDSl2 • 2-pair AtM bonding over

ADSl2 or ADSl2+

• Support for ntR over ADSlx or VDSl2

• Hardware ready to support VDSl2 vectoring

• VDSl2 profile support up to 17a

• environmentally hardened

• Single mode fiber Sc/Apc optical port uplink to an Alcatel-lucent olt

• 28 dB optical budget with up to 20 km reach: B+ optics

• Gigabit ethernet connectivity to SAR-M host

• Support for Gpon physical layer synchronization

• environmentally hardened

• Support for both SHDSl and xDSl in the same module

• Six RJ-11 connectors: four connectors supporting G.SHDSl and two connectors supporting ADSl2/2+/VDSl2

• G.SHDSl 4-, 6- or 8-wire eFM/ ptM bonding

• 2-pair ptM bonding over ADSl2/2+/VDSl2

• 2-pair AtM bonding over ADSl2/2+ • Hardware ready to support VDSl2

vectoring on xDSl interface • Support for ntR over SHDSl and

ADSl2/2+/VDSl2 interfaces • environmentally hardened

The Alcatel-Lucent 7705 SAR-M is only one component of a broadband backhaul solution making use of end-to-end IP/MPLS networking. Alcatel-Lucent’s IP access portfolio builds on the Intelligent Services Access Manager (ISAM) family. The

Alcatel-Lucent ISAM converged access platform portfolio offers a high-density, premium technology for broadband services to the most demanding operators. Stringent backhaul capabilities require an end-to-end solution that scales well, excels in availability, troubleshooting and monitoring tools, and offers advanced Service Level Agreements (SLAs). The ISAM delivers on all of these capabilities while delivering a flexible mix of future-proof access technologies such as xDSL, GPON and point-to-point fiber. A diverse product offering also complements these capabilities with a needs-specific portfolio that includes the following Alcatel-Lucent products: the 7360 ISAM FX Shelf, the 7342 ISAM FTTU, the 7302 ISAM and the 7330 ISAM FTTN.

Deployment options with the SAR-M for broadband backhaul are outlined in Figure 2 and Figure 3.

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aPPendix B: soMe BroadBand

technoLogy Background

dsL background

DSL is the number one broadband choice in the world, with a commanding market share and deep user penetration in all geographies. Operators continue to make significant investments in their DSL infrastructure as evidenced by strong annual DSL port shipments. It is available in every region of the world and can be divided into two broad divisions: asymmetric (ADSL) and symmetric (SDSL).

Symmetric DSL is typically delivered using SHDSL and is geared toward business services. As such, SHDSL deployments tend to be narrowly focused. Asymmetric DSL has commonly been deployed using ADSL, ADSL2, ADSL2+ and now increasingly VDSL2. The evolution from ADSL to VDSL2 is in-line with the requirement to deliver higher throughput rates in support of feature-rich residential broadband services such as IPTV. At the same time, all DSL networks are evolving to become IP-centric. Along with this transition to IP in the DSL access network, to ensure that DSL remains a preferred choice for end-users, service providers are looking for ways to improve the performance of these networks. While VDSL2 and ADSL2+ provide immediate performance improvements over previous versions of ADSL, distance limitations become increasingly difficult to overcome. Multi-pair bonding for ADSL2+ and VDSL2 provide the ideal mix of features: higher bandwidth to all users and the ability to extend the distance that can be reached at a given bandwidth. When multi-pair bonding is combined with IP awareness, the result is a focus on EFM bonding with SHDSL and PTM bonding with VDSL2.

DSL vectoring is the next evolution for VDSL2. It allows for the cancellation of crosstalk between multiple pairs and results in performance gains of up to 50%. Vectoring and multi-pair bonding are very much complementary solutions, both of which are supported by the 7705 SAR, and serve to increase the applicability of copper to high-bandwidth applications such as mobile backhaul and business services. Future “phantom mode” DSL deliverables for Alcatel-Lucent, through Bell Labs research, will additionally add to the longevity of copper and its applicability to these types of services.

With the continuous growth of data traffic over wireless networks, more capacity in the backhaul network is a recurring theme. Adding additional readily available copper pairs to take advantage of HSPA off-load to a more cost-optimal DSL uplink or leveraging pure backhaul via DSL are the two architectural options to examine alongside with DSL.

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gPon background

Service providers continue to push fiber closer to the end user, and a number of

architectures have emerged to support deep-fiber penetration: fiber-to-the-home (FTTH), fiber-to-the-building (FTTB) and fiber-to the-business. These networks are increasingly using PON as a means of delivering last-mile feature-rich content to residential users. There are generally two common variants of PON in active deployment today: Ethernet PON (EPON, standardized by the IEEE) and Gigabit PON (GPON, standardized by the ITU-T).

EPON preceded GPON and was deployed extensively for FTTH in Japan in the early 2000s, and is now the more common PON technology in Asia. However, looking forward, GPON is expected to overtake EPON in China, Asia’s largest market. In North America and in Europe, GPON has already been widely preferred to the virtual exclusion of EPON due to GPON’s superior bandwidth, quality of service (QoS) capabilities, and greater suitability for triple play service bundles.