reliable ip communication for smart grids

A P P L I C A T I O N N O T E

Reliable IP Communication for Smart GridsNetwork transformation to IP/MPLS infrastructures

Abstract

Communications network transformation to a highly available IP/MPLS infrastructure for mission-critical communications is a foundation to the Smart Grid architecture. Alcatel-Lucent delivers a converged IP/MPLS-based communications network for power utilities using next-generation products and management tools. Alcatel-Lucent IP/MPLS products support network resiliency, quality of service, virtualization, convergence and a management platform that automates and simplifies operations management. Reliable communication is essential to meet key Smart Grid application requirements of increased use of information management technologies.

Table of contents

1 Introduction

1 The traditional utility communications network

1 Bandwidth and Quality of Service

2 CAPEX/OPEX and scalability

3 Next-generation communications network requirements

3 Bandwidth

4 Security

4 Reliability

4 Manageability

4 The Alcatel-Lucent next-generation utility communications network

4 Alcatel-Lucent IP/MPLS infrastructure building blocks

6 The network topology

8 CAPEX/OPEX and scalability

8 Multiservice support

9 Virtualization

10 Teleprotection over MPLS

11 Synchronous Ethernet

12 High Availability through MPLS

12 Quality of Service

12 Effective management for easier day-to-day operations

13 Conclusion

13 Acronyms

Reliable IP Communication for Smart Grids | Application Note 1

Introduction

The implementation of Smart Grids is part of the new energy delivery strategy of many power utilities around the world. Smart Grid applications provide utilities with better automation and the benefits of reduced operating costs, increased power quality, and improved outage response. Governments consider Smart Grid technologies as a means to better power quality, reduced need for additional generation capacity, and reduced carbon emissions. Consumers can take advantage of new features (such as time-of-day charging) and the participation from independent producers.

The Smart Grid architecture includes many applications such as transmission substation automation, distribution automation, demand response, and distributed generation. These applications require incorporating information management technologies and extending control and monitoring throughout the wider transmission and distribution networks as well as new renewable power generation sources.

A key enabler for the safe and efficient transformation of a power utility network is a modern, reliable, and flexible communications infrastructure that forms the core network in order to route the monitoring, control and status data effectively, efficiently and on time. There is a wide expectation that IP-based networks will serve as a key element for the Smart Grid information networks. This requires many power utilities to consider an evolution of their communications infrastructures that would be very different from their traditional Time Division Multiplexing (TDM) centric networks.

A flexible transformation is required to preserve existing investments and to minimize risks. Alcatel-Lucent IP/MPLS communications infrastructure incorporates state-of the-art technologies to enable a power utility to deploy a future-proof, highly available IP network to continue supporting existing TDM and legacy applications while providing a smooth migration path to IP, Ethernet and MPLS-based services. This new IP/MPLS infrastructure will allow the utility to maximize the cost-effectiveness and efficiency of its network without jeopardizing reliability, as well as enabling the deployment of new devices and applications that can improve operational and workflow efficiency. A highly available IP/MPLS communications infrastructure is ideally suited to support both mission-critical operations and corporate communications requirements.

In addition, the Alcatel-Lucent network and service management platform allows power utilities to improve their efficiency by automating and simplifying operations management for communications services, thus reducing the barrier in introducing MPLS-based technologies and services.

This application note illustrates the advantage of using IP/MPLS at the core of the network while leveraging microwave wireless and/or fiber optics transport where appropriate, all within an integrated and end-to-end communications infrastructure.

The traditional utility communications network

Utility communications networks are traditionally built to carry information between the utility control center and all remote sites — information that is used to manage capacity, to monitor and control the system, to bill customers and to provide mobile radio communication. Traffic is typically carried over TDM-based circuits like RS-232, V.35, and E&M.

Bandwidth and Quality of ServiceTDM networks support high reliability levels such as unidirectional path-switched ring (UPSR) when using Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH), which allows a utility communications network to recover from a failure in less than 50 milliseconds.

Reliable IP Communication for Smart Grids | Application Note2

With SONET/SDH, the circuits are established in a static configuration, usually in increments of VT1.5 (1.5 Mb/s) or TU-12 (2 Mb/s). This approach is deployed in many utility communications networks today, but it means that the bandwidth is reserved for a particular circuit, whether it is used or not. Consequently, one application may have insufficient bandwidth while bandwidth that is reserved for an inactive application sits idle. As such, this approach is not optimized to support IP and Ethernet-centric communications required for new Smart Grid applications.

Because each circuit in a traditional TDM implementation is set with predefined bandwidth, quality of service (QoS) is inherent in the system; once the circuit is set, an application can only utilize the bandwidth assigned to it. When new IP-based services are being integrated over a common infrastructure with TDM, the network needs to be able to discriminate between high-priority critical traffic and lower-priority traffic, while enforcing upper bounds on delay and jitter across the network.

Figure 1 shows a traditional utility SONET/SDH/TDM network. Typically, management and control functions are centralized at one location and linked via the network to all substations. The control center is connected to the network at up to an OC-3/STM-1 rate, and the substations may be connected by fiber or through a wireless connection at NxT1/E1 rates.

Figure 1. Traditional SONET/SDH/TDM implementation

CAPEX/OPEX and scalabilityIn a SONET/SDH setting, the granularity of the bandwidth tends to be in the order of VT1.5 or TU-12, which is a 1.5 Mb/s or 2 Mb/s increment respectively. As IP-based applications converge over SONET/SDH networks, bandwidth can quickly be exhausted. Operational complexity also grows when running IP applications on top of a TDM infrastructure. Power utilities must consider

OPS voice

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cost-effectiveness when evaluating any new network or service. The utility must be able to add applications and services without negatively impacting operating costs associated with equipment and maintenance, network carrier charges, and network administration.

Next-generation communications network requirements

Today, power utilities are aggressively pursuing communications options that will result in improved operational efficiency and increased productivity as well as prepare them for Smart Grid deployment. This means that many parameters must be kept in balance. First, the solution must be highly reliable: In a mission-critical environment, no compromise is acceptable. Second, capital expenditures (CAPEX) and operating expenditures (OPEX) must be minimized. Finally, the network should offer the opportunity to implement new services in a rapid and cost-effective manner. The ideal solution is one that offers at least the same level of reliability, QoS and security as that of traditional utility communications networks while supporting the full array of both TDM and new IP/Ethernet services that are needed for core utility operations and administration.

New technologies provide utilities with the opportunity to migrate traditional applications to more efficient IP and Ethernet technologies and to implement new IP-centric applications, such as:

• IP-basedmobileradio

• Ethernetsupervisorycontrolanddataacquisition(SCADA)

• IP-basedvideosurveillance

• Collaborationtools

• VoiceoverIP(VoIP)

• WiFimobility

It is expected that IP and Ethernet will be the key communications protocols for the Smart Grids. IP technology can increase operational efficiency, supporting existing critical applications while providing the benefits of the new applications. Below are some of the drivers behind this migration to IP:

• ThereisalargenumberofmatureIPstandardsandexcellentavailabilityoftoolsandapplicationsthat can be applied to Smart Grid environments. IP technologies serve as a bridge between applications and the underlying communication medium.

• TheIEC61850protocoltakesadvantageoftheincreaseinbandwidththatmodernnetworkingtechnologiesoffer.IEC61850-basedintelligentelectronicsdevices(IED)thatuseEthernetandTCP/IP for efficient communications are easier to scale and implement than legacy approaches.

• LegacySCADAsystemstendtobeexpensive,complexanddifficulttocommissionanddeploy.Ethernet SCADA allows for a simplified architecture, efficient bandwidth utilization, and decreased dependence on SCADA vendors.

• Videosurveillanceisusedtoensurethephysicalsecurityofcriticalassets.Amodernvideosurveillance system is IP-based, and it is becoming integrated with the information technology infrastructure of the utilities.

BandwidthThe growth in IP applications drives the need for bandwidth and, more importantly, the need for bandwidth flexibility and efficiency. The new IP-centric applications tend to exhibit “bursty” traffic behavior: The application grabs a high level of bandwidth to send a large amount of traffic, then, when the transmission ends, releases the bandwidth for other applications. With a traditional TDM core implementation, running multiple services of this type becomes a challenge. The utility operator needs a service-aware network that can support legacy, IP and Ethernet applications without jeopardizing system availability.


SecurityExisting and new applications require a communication network to support a large variety of traffic profiles and interconnection topologies. The network needs to securely transport this broad range of applications over one physical infrastructure. Therefore, the network needs to support and maintain traffic separation and bandwidth traffic engineering, and to restrict access to the authorized traffic on configured ports. As with an optical SONET/SDH-based network, the network needs to be reliable and resistant to security attacks.

ReliabilityThe network must offer the necessary level of reliability to maintain uninterrupted operation for voice, data and video traffic. A single failure in the network should not be service-affecting. Service interruptions in utility environments can include consumers losing power, overload conditions, loss of communication over mobile radio, or the development of other potentially unsafe conditions. TDM systems traditionally support high levels of reliability such as UPSR when using SONET/SDH, allowing a utility to recover from a failure in less than 50 milliseconds. That level of service must be matched in a new IP-based network.

ManageabilityThe management of a utility communications network has a direct impact on the operational cost of maintaining and scaling the network. OPEX should not escalate exponentially as new services are added. Service-aware management software can simplify network operations while streamlining operational processes such as maintenance, troubleshooting, scaling and commissioning.

The Alcatel-Lucent next-generation utility communications network

The utility communications network must:

• SupportexistingcriticalTDMservices

• SupportnewIP-basedandEthernet-basedapplicationsandservices

• Minimizecostswithoutcompromisingfeatures,functionalityandreliability

• Scale,allowingtheutilitytoincreaseservicesandgrowthenumberofusers,applicationsandcapacity

• Ensurenetworkandoperationalsystemsecurity

• Behighlyavailableandresilient,withnosinglepointoffailure

• EnablescalableQoStoprioritizemission-criticalapplicationsoverothertraffic

• Providereliabletransmissionoverwirelessmicrowaveandfiberopticsystems

There is a clear movement towards implementing an IP-based core network for a power utility for all of its communications needs. Not all IP-based solutions are appropriate for power utilities. To support the mission-critical traffic of power utilities, an IP/MPLS-based communications infrastructure is needed. An IP/MPLS network can support all traffic types and leverage the benefits of microwave and fiber optics where appropriate.

An increasing number of power utilities are deploying their own IP/MPLS networks. MPLS brings the advantages of a circuit-based network to an IP network, and enables network convergence, virtualization and resiliency.

Alcatel-Lucent IP/MPLS infrastructure building blocksThe Alcatel-Lucent IP/MPLS communications infrastructure leverages multiple state-of-the-art technologies to enable a utility network to continue supporting existing TDM-based applications while providing a smooth migration path to IP and Ethernet services. The service-aware infrastructure efficiently supports the full range of IP and legacy applications, ensuring that each application can


be allocated the resources that it needs in terms of bandwidth, QoS level, security, availability, and so on. The Alcatel-Lucent IP/MPLS implementation provides a service-oriented approach that focuses on service scalability and quality, as well as per-service operations, administration and maintenance (OAM).

The components of the Alcatel-Lucent IP/MPLS infrastructure, which extends MPLS capabilities from the core to access, are based on and can include:

• Alcatel-Lucent7750ServiceRouter(SR)

• Alcatel-Lucent7705ServiceAggregationRouter(SAR)

• Alcatel-Lucent7450EthernetServiceSwitch(ESS)

• Alcatel-Lucent7210ServiceAccessSwitch(SAS)

• Alcatel-LucentOmniSwitch™6855HardenedLANSwitch(HLS)

• Alcatel-Lucent5620ServiceAwareManager(SAM)

• Alcatel-Lucent5650ControlPlaneAssuranceManager(CPAM)

These Alcatel-Lucent products support routing, switching and multiservice capabilities, enabling the power utilities to support real-time applications across the full extent of the network. The Alcatel-Lucent IP/MPLS implementation includes non-stop routing and non-stop service capabilities that provide unparalleled reliability.

The network and service administration of the Alcatel-Lucent IP/MPLS communications infrastructure ishandledbytheindustry-leadingAlcatel-Lucent5620SAM,anintegratedapplicationthatcoversall aspects of element, network and service management on one platform. It simplifies the programming and management of the network, including automating routine tasks, correlating alarms to problems, managing the assignment of end-to-end connections, and facilitating the introduction and administration ofnewservices,allthroughauser-friendlypoint-and-clickinterface.TheAlcatel-Lucent5620SAMcan also manage many of the other Alcatel-Lucent and third-party elements within the network.

ForIProutingmanagementcontrol,theAlcatel-Lucent5650CPAMoffersreal-timecontrolplanevisualization, proactive control plane surveillance, configuration, validation and diagnosis. It enables power utilities to overlay Layer 2 and Layer 3 services, MPLS tunnels and various OAM traces on the control plane map. This simplifies problem resolution, reduces control plane configuration errors, and reduces troubleshooting time.

The services enabled by the IP/MPLS communications infrastructure include, but are not limited to:

• Teleprotection

• SCADA

• Voice(operationsandcorporate)

• Mobileradio

• Accesscontrol

• Videoconferencing

• WirelessIPdataaccesspointsforworkforcemobility

• Alarmcircuits

• Virtualprivatenetworks(VPNs)

• Metering

• IP-basedvideosurveillance

• CorporateLAN/Internet

• OperationsLAN


Figure 2 shows an overview of the Alcatel-Lucent next-generation utility IP/MPLS communications infrastructure.

Figure 2. Alcatel-Lucent IP/MPLS communications infrastructure

The Alcatel-Lucent IP/MPLS communications infrastructure comprises an MPLS-based core network that connects the control center (and backup center) with remote sites and substations with a SONET/SDH-like reliability of sub-50 milliseconds recovery. At each substation, an IP/MPLS switch/router aggregates traffic from applications such as IED/RTU for SCADA, WiFi access point, VoIP, corporate network access, access control, and video surveillance onto the core network for intra-substation or control center communications. In an Ethernet-centric implementation, the 7210SASisusedtoaggregateEthernetandIPtrafficfromthevariousapplicationsbacktothecontrol center or to neighboring substations. For a substation with TDM connectivity requirements, the7705SAR,whilehandlingIPandEthernettraffic,canalsonativelysupportRTUserialinterfacesfor SCADA, analog voice interfaces for operations voice, and a T1/E1 connection from a multiplexer. With this IP/MPLS network, traffic is now packet-based, and bandwidth in the core network is shared while QoS for critical traffic is strictly maintained. Both IP and TDM services are concurrently supported by the same IP/MPLS switch/router, reducing the overall number and costs oftelecomequipmentrequired.AsubstationLANcanbeimplementedwiththeOS6855-hardenedEthernet switch.

The network topologyA network topology is determined by the graphical mapping of the physical and logical interconnections. The IP/MPLS network is deployed on a ring-based architecture or on partially-meshed architecture (Figure 3).

InternetApplicationservers

EMS/DMS OmniPCX SCADA,metering,

alarms

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Figure 3. Typical ring and partially-meshed architectures

A ring architecture provides an efficient, reliable environment — as traffic can be rerouted in the opposite direction of the ring, should a failure occur. In a SONET/SDH application, every node is typically transmitting in both directions to provide end-to-end protection, effectively duplicating all traffic on the ring. In the Alcatel-Lucent IP/MPLS infrastructure, the network relies on the IP/MPLS fast reroute (FRR) feature for resiliency, which eliminates the requirement to duplicate the traffic on the ring. All the bandwidth can then be fully utilized and FRR ensures traffic is rerouted in sub-50 milliseconds in the event of a node or link failure in the ring, preserving all traffic on the ring. This topology is often used in the aggregation part of the network and offers a very efficient way to aggregate and backhaul traffic over a relatively low number of links.

Traffic engineering is used to efficiently carry the traffic over the different meshed links across the core of the network. A partially-meshed architecture uses more links and therefore provides more rerouting alternatives. Partially-meshed networks are able to recover from double faults and are often deployed in the core of the network.

Microwave can be used to provide connectivity coverage to one or several sections of the network. An optical layer, Coarse Wavelength Division Multiplexing (CWDM) and Dense Wavelength Division Multiplexing (DWDM), can also be used for increasing backbone network capacity.

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CAPEX/OPEX and scalabilityTo meet utilities growing requirements in terms of service deployment and bandwidth, the Alcatel-Lucent IP/MPLS communications infrastructure is extremely scalable, with the bandwidth in each ring able to scale up or down independently, according to changing requirements. The IP/MPLS network can accommodate a growing number of applications and services. The granularity in MPLS bandwidth, scaling options and statistical multiplexing results in minimal CAPEX requirements to deploy and scale this infrastructure. The converged architecture and the ease of Ethernet technology allow for optimized OPEX. A converged network also reduces the number of network elements required, thus reducing costs.

Multiservice supportThe Alcatel-Lucent IP/MPLS communications infrastructure offers a flexible network and service environment that enables the continuing support of existing services while incorporating new IP-based applications. The IP-based applications are typically more efficient in terms of bandwidth usage when deployed over an IP/MPLS infrastructure. All services converge at the access of the network, where the required MPLS packet handling, such as encapsulation and QoS capabilities are executed. Different applications are transported via dedicated VPNs in a point-to-point, point-to-multipoint or multipoint-to-multipoint manner. The network also supports the migration of the TDM-based services on to the IP/MPLS infrastructure.

Circuit Emulation Service over MPLS

Utilities need to consider how to leverage new IP/MPLS network technologies when migrating legacy TDM systems and services. Utilities can take advantage of the IP/MPLS Circuit Emulation Service (CES) functionality and transition their legacy applications gradually. CES delivers the same quality of experience as the existing TDM network infrastructure, with the same level of predictability. The Alcatel-Lucent IP/MPLS network has a circuit emulation interworking function that ensures all information required by a TDM circuit is maintained across the packet network. This provides a full transition to a packet network over time while providing TDM service continuity.

Two principal types of circuit emulation can be used: Circuit Emulation Service over Packet (CESoPSN) and Structured Agnostic TDM over Packet (SAToP). CESoPSN allows NxDS0 service, including full T1/E1 capability. SAToP provides the ability to carry unstructured T1/E1 circuits across the IP/MPLS network.

InanIP/MPLSnetwork,theMPLStunnelisusedasthetransportlayer(Figure4).APseudowire(PWE3)is created to identify the specific TDM circuit within the MPLS tunnel. Circuit emulation interworking function ensures that all information required by the T1/E1 circuit is maintained across the packet network. This provides a transparent service to the end devices.

Figure 4. Circuit Emulation Service functionality overview

CES IWF

The CES interworking function(IWF) applies to the properencapsulation to the nxDS0

or T1/E1 traffic

Flexible configuration tobuffers within the CESIWF allows control ofpacketization, latencyand jitter (to meet the

requirements forTDM services)

Pseudowiresidentify the specific

CES connection

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from point A to B

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Virtualization The Alcatel-Lucent IP/MPLS communications infrastructure provides for the virtual isolation of various traffic types on a single infrastructure. This allows the full separation of traffic from different applications or operations within the utility, allowing for a secure environment and effective bandwidth allocation. Advanced MPLS VPNs — such as virtual private LAN service (VPLS) and IP virtual private networks (IP-VPNs) — are supported which can be used to provide different applications or user groups an environment that is private and unaffected by other traffic. One service is carried across one VPN while the traffic of different services is securely separated in their own VPN, effectively providing separate private networks. Figure 5 shows the different VPNs that are supported on the Alcatel-Lucent IP/MPLS communications infrastructure.

Figure 5. MPLS-based VPN services

Layer 2 VPNs

Layer 2 VPNs include pseudowire and VPLS.

A pseudowire encapsulates traffic over label switched paths (LSPs) to create a point-to-point service. An MPLS pseudowire is analogous to a private line within the MPLS infrastructure. It offers a point-to-point connection between any two end devices. Figure 5.1. depicts three different types of pseudowire — TDM, ATM, and Ethernet. The pseudowire can be used for applications that require dedicated point-to-point connectivity such as supporting existing point-to-point TDM circuits for voice or legacy SCADA RTUs.

VPLS service

Virtual bridge

2. Virtual Private LAN Services (VPLS) Layer 2 bridged multipoint Ethernet service

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VPLS is another approach of a Layer 2 VPN. VPLS is a bridged multipoint service that forwards traffic based on the media access control (MAC) address. A VPLS service is protocol-independent and enables multipoint connectivity at Layer 2 within the MPLS infrastructure. Figure 5.2. depicts two VPLS instances within a network. VPLS is composed of virtual bridges at each node. Each virtual bridge performs MAC learning and constructs a table that maps MAC addresses and cor-responding MPLS paths. The VPLS concept is similar to a logical LAN connection where all end devices connected to the VPLS appear as if they are within the same LAN segment. For utilities, a VPLS service can be used to support Ethernet-based SCADA systems.

Layer 3 VPN

An IP-VPN is a Layer 3 VPN and is implemented specifically for IP traffic only. An IP-VPN is a routed service that forwards traffic based on the IP address. An IP-VPN enables multipoint connectivity at Layer 3 within the MPLS infrastructure (Figure 5.3.). With IP-VPNs, each MPLS node supports virtual routing and forwarding (VRF) instances. An IP-VPN can be used to support multiple independent departmental networks with no routing table interactions among the different VRF instances.

Teleprotection over MPLSTeleprotection systems monitor and compare conditions on transmission lines for coordinated tripping of transmission lines to quickly isolate faults in order to prevent damages to expensive substation equipment and instability in the power system. These systems rely on the communications network for real-time status exchange between teleprotection relays (TPR). To ensure the power system is protected, relay signals must be transferred with minimal latency.

The Alcatel-Lucent IP/MPLS network can support the stringent latency requirement for teleprotection. Setting up the right quality of service in an MPLS network will enable the network to discriminate among various types of traffic and advance higher priority protective relay traffic over lower priority traffic. An Alcatel-Lucent IP/MPLS network can manage protective relay traffic flows to ensure performance parameters like bandwidth, delay, and jitter are met. This minimizes the need to maintain a parallel TDM network for teleprotection.

Figure6showshowteleprotectioncanbesupportedbytheAlcatel-LucentIP/MPLSnetwork.TheinterfacefromtheteleprotectionrelaycanbeG.703,E&M,orRS-232.FortraditionalTDM-basedimplementation, these relay interfaces are connected to a multiplexer for TPR signal transport via a T1/E1 and over SONET/SDH or microwave links to the next substation. With the migration to an IP/MPLSnetwork,anAlcatel-Lucent7705SARcanbeusedtosupportteleprotection.Forexample,relaysignalsviaRS-232orE&Mcanbeconnecteddirectlytothe7705SARforpseudowireconnectiontothefarend7705SAR.Alternatively,incaseswhereamultiplexeriscontinuingtobeused,aT1/E1fromthemultiplexercanbeterminatedontothe7705SAR.


Figure 6. Using an MPLS network for teleprotection

IEC68150standardforGenericObjectOrientedSubstationEvents(GOOSE)messagingoverEthernet was originally intended for intra-substation communications but is now being expanded to includeinter-substationcommunications.ForthisEthernet-basedimplementation,the7705SARcan support protective relay traffic over Ethernet with VPLS service.

Synchronous EthernetIn most TDM networks, synchronization is distributed within the network using the SONET/SDH mechanisms built into the physical layer definition. To deliver the TDM service via a packet network, the same synchronization must be achieved through other means. Some TDM applications require stratum-level clocking and distribution of information with very stringent accuracy. Utilities are looking to migrate their synchronization infrastructures to a familiar and manageable model. To enable rapid migration of these networks, synchronous Ethernet may be the easiest and quickest way to achieve (frequency) synchronization and to allow the benefits of an Ethernet network infrastructure to be realized without any change to the existing TDM network applications. The concept behind Synchronous Ethernet is similar to SONET/SDH system timing capabilities.

With Synchronous Ethernet, the network elements derive the physical layer transmitter clock from a high-quality frequency reference via the physical Ethernet interfaces. This does not affect the operation of any of the Ethernet layers and is transparent to them. The receiver at the far end of the link locks onto the physical layer clock of the received signal, and thus itself gains access to a highly accurate and stable frequency reference. Then, in a way similar to conventional hierarchical master-slave network synchronization, this receiver locks the transmission clock of its other ports to the frequency reference and a fully synchronous network is established. The implementation of Synchronous Ethernet will allow a utility to gracefully integrate its existing systems and future deployments into a conventional industry-standard synchronization hierarchy. The Alcatel-Lucent IP/MPLS products support Synchronous Ethernet, which has proven to out-perform the standards requirements used by SONET/SDH, allowing migration from SONET/SDH to a full IP/MPLS network as desired.

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High Availability through MPLSWith the Alcatel-Lucent IP/MPLS communications infrastructure, utilities have the necessary reliability level to maintain uninterrupted operations. Network resiliency is achieved by means of the end-to-end restoration capabilities of the MPLS FRR feature. The MPLS FRR feature enables the network to reroute connections around a failure in less than 50 milliseconds. Because the network is service aware, FRR can distinguish and prioritize traffic redirection according to priority. To protect the network against node or interconnection failures, end-to-end standby MPLS paths are provisioned.

The Alcatel-Lucent MPLS implementation includes the unique additional High Availability features of non-stop routing and non-stop services. The benefits are unparalleled availability and reliability:

• Non-stoprouting– ensures that a control card failure has no service impact. Label Distribution Protocol (LDP) adjacencies, sessions and the database remain intact if there is a switchover.

• Non-stopservice– ensures that VPN services are not affected when there is a Control Fabric Module switchover.

Quality of ServiceIn a utility environment where multiple services converge over a common infrastructure, QoS is essential. The Alcatel-Lucent IP/MPLS communications infrastructure enables the network to discriminate among various types of traffic, based on a rich set of classification attributes (including MACaddress,IEEE802.1p,andIPaddresses)andprioritizetransmissionofhigherprioritytrafficover lower priority. The Alcatel-Lucent hierarchical quality of service (H-QoS) implementation also allows lower priority traffic to burst in order to fill available bandwidth when higher priority applications go idle. H-QoS uses an advanced scheduling mechanism to implement service hierarchies. These hierarchies provide maximum isolation and fairness across different traffic while optimizing uplink utilization. With multiple levels and instances of shaping, queuing and priority scheduling, the Alcatel-Lucent IP/MPLS network can manage traffic flows to ensure that performance parameters (such as bandwidth, delay and jitter) for each application are met.

Effective management for easier day-to-day operationsA key element of reliable and flexible MPLS communications infrastructure is a set of effective, simplified management tools that provide easy configuration and control of the network, effective problem isolation and resolution, and support of new management applications. The Alcatel-Lucent IP/MPLS network supports OAM tools that simplify the deployment and day-to-day operation of a utility communications network. For example, service tests, interface tests and tunnel tests allow for rapid troubleshooting and enable proactive awareness of the state of traffic flows to help minimize service downtime.

The Alcatel-Lucent IP/MPLS network is fully managed by the industry-leading Alcatel-Lucent 5620ServiceAwareManager,whichautomatesandsimplifiesoperationsmanagementonaconvergedMPLS network, driving network operations to a new level of efficiency. The Alcatel-Lucent 5650ControlPlaneAssuranceManagerprovidessimplifieddiagnosisandintuitivevisualizationofthe relationship between services, the MPLS infrastructure and the routing plane.


Conclusion

Utilities are experienced at building and operating reliable and effective networks to ensure the delivery of essential information and maintain flawless service delivery. The Alcatel-Lucent IP/MPLS communications infrastructure can enable a utility to extend and enhance its network with new technologies like IP, Ethernet and MPLS. These new technologies will enable the utility to optimize its network in order to reduce both CAPEX and OPEX without jeopardizing reliability. Advanced technologies also allow the introduction of new Smart Grid applications that can improve operational and workflow efficiency within the utility. Alcatel-Lucent leverages cutting edge technologies, along with the company’s broad and deep experience in the utility industry, to help utilities build better, next-generation networks with IP/MPLS.

AcronymsCCTV closed-circuit television

CES Circuit Emulation Service

CPAM Control Plane Assurance Manager

CWDM Coarse Wavelength Division Multiplexing

DWDM Dense Wavelength Division Multiplexing

ESS Ethernet Service Switch

FRR Fast Reroute

H-QoS Hierarchical Quality of Service

IP VPN IP virtual private network

LDP Label Distribution Protocol

MPLS Multiprotocol Label Switching

QoS Quality of Service

SAM Service Aware Manager

SAR Service Aggregation Router

SAS Service Access Switch

SDH Synchronous Digital Hierarchy

SONET Synchronous Optical Network

SR Service Router

TDM Time Division Multiplexing

VPLS Virtual Private LAN Service

VPN virtual private network

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