march 2010 ip comms for smart grid an
Post on 08-Apr-2018
215 Views
Preview:
TRANSCRIPT
-
8/7/2019 March 2010 IP Comms for Smart Grid An
1/17
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
-
8/7/2019 March 2010 IP Comms for Smart Grid An
2/17
Abstract
Communications network transormation to a highly available IP/MPLS inrastructure ormission-critical communications is a oundation to the Smart Grid architecture. Alcatel-Lucentdelivers a converged IP/MPLS-based communications network or power utilities using next-generationproducts and management tools. Alcatel-Lucent IP/MPLS products support network resiliency, qualityo service, virtualization, convergence and a management platorm that automates and simplies
operations management. Reliable communication is essential to meet key Smart Grid applicationrequirements o increased use o inormation management technologies.
-
8/7/2019 March 2010 IP Comms for Smart Grid An
3/17
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 topology8 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
-
8/7/2019 March 2010 IP Comms for Smart Grid An
4/17
Reliable IP Communication for Smart Grids | Application Note 1
Introduction
The implementation o Smart Grids is part o the new energy delivery strategy o many powerutilities around the world. Smart Grid applications provide utilities with better automation andthe benets o reduced operating costs, increased power quality, and improved outage response.Governments consider Smart Grid technologies as a means to better power quality, reduced needor additional generation capacity, and reduced carbon emissions. Consumers can take advantage
o new eatures (such as time-o-day charging) and the participation rom independent producers.
The Smart Grid architecture includes many applications such as transmission substation automation,distribution automation, demand response, and distributed generation. These applications requireincorporating inormation management technologies and extending control and monitoringthroughout the wider transmission and distribution networks as well as new renewable powergeneration sources.
A key enabler or the sae and ecient transormation o a power utility network is a modern,reliable, and fexible communications inrastructure that orms the core network in order to routethe monitoring, control and status data eectively, eciently and on time. There is a wide expectationthat IP-based networks will serve as a key element or the Smart Grid inormation networks. This
requires many power utilities to consider an evolution o their communications inrastructures thatwould be very dierent rom their traditional Time Division Multiplexing (TDM) centric networks.
A fexible transormation is required to preserve existing investments and to minimize risks.Alcatel-Lucent IP/MPLS communications inrastructure incorporates state-o the-art technologiesto enable a power utility to deploy a uture-proo, highly available IP network to continue supportingexisting TDM and legacy applications while providing a smooth migration path to IP, Ethernetand MPLS-based services. This new IP/MPLS inrastructure will allow the utility to maximize thecost-eectiveness and eciency o its network without jeopardizing reliability, as well as enablingthe deployment o new devices and applications that can improve operational and workfow eciency.A highly available IP/MPLS communications inrastructure is ideally suited to support bothmission-critical operations and corporate communications requirements.
In addition, the Alcatel-Lucent network and service management platorm allows power utilities toimprove their eciency by automating and simpliying operations management or communicationsservices, thus reducing the barrier in introducing MPLS-based technologies and services.
This application note illustrates the advantage o using IP/MPLS at the core o the network whileleveraging microwave wireless and/or ber optics transport where appropriate, all within an integratedand end-to-end communications inrastructure.
The traditional utility communications network
Utility communications networks are traditionally built to carry inormation between the utility
control center and all remote sites inormation that is used to manage capacity, to monitor andcontrol the system, to bill customers and to provide mobile radio communication. Trac is typicallycarried over TDM-based circuits like RS-232, V.35, and E&M.
Bandwidth and Quality of Service
TDM 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 rom a ailure in less than 50 milliseconds.
-
8/7/2019 March 2010 IP Comms for Smart Grid An
5/17
Reliable IP Communication for Smart Grids | Application Note2
With SONET/SDH, the circuits are established in a static conguration, usually in increments oVT1.5 (1.5 Mb/s) or TU-12 (2 Mb/s). This approach is deployed in many utility communicationsnetworks today, but it means that the bandwidth is reserved or a particular circuit, whether it isused or not. Consequently, one application may have insucient bandwidth while bandwidth thatis reserved or an inactive application sits idle. As such, this approach is not optimized to supportIP and Ethernet-centric communications required or new Smart Grid applications.
Because each circuit in a traditional TDM implementation is set with predened bandwidth, qualityo service (QoS) is inherent in the system; once the circuit is set, an application can only utilize thebandwidth assigned to it. When new IP-based services are being integrated over a common inrastructurewith TDM, the network needs to be able to discriminate between high-priority critical trac andlower-priority trac, while enorcing upper bounds on delay and jitter across the network.
Figure 1 shows a traditional utility SONET/SDH/TDM network. Typically, management and controlunctions are centralized at one location and linked via the network to all substations. The controlcenter is connected to the network at up to an OC-3/STM-1 rate, and the substations may be connectedby ber or through a wireless connection at NxT1/E1 rates.
Figure 1. Traditional SONET/SDH/TDM implementation
CAPEX/OPEX and scalability
In a SONET/SDH setting, the granularity o the bandwidth tends to be in the order o VT1.5 orTU-12, which is a 1.5 Mb/s or 2 Mb/s increment respectively. As IP-based applications convergeover SONET/SDH networks, bandwidth can quickly be exhausted. Operational complexity alsogrows when running IP applications on top o a TDM inrastructure. Power utilities must consider
OPS voice
n x T1/E1 n x T1/E1 n x T1/E1
Multiplexer
SONET/SDHADM
Corporate access
InternetApplicationservers
EMS PBX
SCADA
TPR
SubstationControl center Substation Substation
OC-3/STM-1n x E1
OC-3/STM-1
TPRTPR
RTUs RTUsRTUs
Multiplexer Multiplexer
OPS voice OPS voice
OPS LAN OPS LAN
-
8/7/2019 March 2010 IP Comms for Smart Grid An
6/17
Reliable IP Communication for Smart Grids | Application Note 3
cost-eectiveness when evaluating any new network or service. The utility must be able to addapplications and services without negatively impacting operating costs associated with equipmentand 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 eciency and increased productivity as well as prepare them or Smart Grid deployment.This means that many parameters must be kept in balance. First, the solution must be highly reliable: Ina mission-critical environment, no compromise is acceptable. Second, capital expenditures (CAPEX)and operating expenditures (OPEX) must be minimized. Finally, the network should oer theopportunity to implement new services in a rapid and cost-eective manner. The ideal solution isone that oers at least the same level o reliability, QoS and security as that o traditional utilitycommunications networks while supporting the ull array o both TDM and new IP/Ethernet servicesthat are needed or core utility operations and administration.
New technologies provide utilities with the opportunity to migrate traditional applications to moreecient 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 or the Smart Grids.IP technology can increase operational eciency, supporting existing critical applications while providingthe benets o the new applications. Below are some o the drivers behind this migration to IP:
ThereisalargenumberofmatureIPstandardsandexcellentavailabilityoftoolsandapplications
that can be applied to Smart Grid environments. IP technologies serve as a bridge betweenapplications and the underlying communication medium.
TheIEC61850protocoltakesadvantageoftheincreaseinbandwidththatmodernnetworkingtechnologiesoffer.IEC61850-basedintelligentelectronicsdevices(IED)thatuseEthernetandTCP/IP or ecient communications are easier to scale and implement than legacy approaches.
LegacySCADAsystemstendtobeexpensive,complexanddifculttocommissionanddeploy.Ethernet SCADA allows or a simplied architecture, ecient bandwidth utilization, and decreaseddependence on SCADA vendors.
Videosurveillanceisusedtoensurethephysicalsecurityofcriticalassets.Amodernvideosurveillance system is IP-based, and it is becoming integrated with the inormation technologyinrastructure o the utilities.
Bandwidth
The growth in IP applications drives the need or bandwidth and, more importantly, the need orbandwidth fexibility and eciency. The new IP-centric applications tend to exhibit bursty tracbehavior: The application grabs a high level o bandwidth to send a large amount o trac, then,when the transmission ends, releases the bandwidth or other applications. With a traditional TDMcore implementation, running multiple services o this type becomes a challenge. The utility operatorneeds a service-aware network that can support legacy, IP and Ethernet applications without jeopardizingsystem availability.
-
8/7/2019 March 2010 IP Comms for Smart Grid An
7/17
Reliable IP Communication for Smart Grids | Application Note4
Security
Existing and new applications require a communication network to support a large variety o tracproles and interconnection topologies. The network needs to securely transport this broad range oapplications over one physical inrastructure. Thereore, the network needs to support and maintaintrac separation and bandwidth trac engineering, and to restrict access to the authorized tracon congured ports. As with an optical SONET/SDH-based network, the network needs to be reliableand resistant to security attacks.
Reliability
The network must oer the necessary level o reliability to maintain uninterrupted operation orvoice, data and video trac. A single ailure in the network should not be service-aecting. Serviceinterruptions in utility environments can include consumers losing power, overload conditions, losso communication over mobile radio, or the development o other potentially unsae conditions.TDM systems traditionally support high levels o reliability such as UPSR when using SONET/SDH,allowing a utility to recover rom a ailure in less than 50 milliseconds. That level o service must bematched in a new IP-based network.
Manageability
The management o a utility communications network has a direct impact on the operational costo maintaining and scaling the network. OPEX should not escalate exponentially as new servicesare added. Service-aware management sotware can simpliy network operations while streamliningoperational 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-criticalapplicationsoverothertrafc
Providereliabletransmissionoverwirelessmicrowaveandberopticsystems
There is a clear movement towards implementing an IP-based core network or a power utility or allo its communications needs. Not all IP-based solutions are appropriate or power utilities. To supportthe mission-critical trac o power utilities, an IP/MPLS-based communications inrastructure isneeded. An IP/MPLS network can support all trac types and leverage the benets o microwaveand ber optics where appropriate.
An increasing number o power utilities are deploying their own IP/MPLS networks. MPLS bringsthe advantages o a circuit-based network to an IP network, and enables network convergence,virtualization and resiliency.
Alcatel-Lucent IP/MPLS infrastructure building blocks
The Alcatel-Lucent IP/MPLS communications inrastructure leverages multiple state-o-the-arttechnologies to enable a utility network to continue supporting existing TDM-based applicationswhile providing a smooth migration path to IP and Ethernet services. The service-aware inrastructureeciently supports the ull range o IP and legacy applications, ensuring that each application can
-
8/7/2019 March 2010 IP Comms for Smart Grid An
8/17
Reliable IP Communication for Smart Grids | Application Note 5
be allocated the resources that it needs in terms o bandwidth, QoS level, security, availability,and so on. The Alcatel-Lucent IP/MPLS implementation provides a service-oriented approach thatocuses on service scalability and quality, as well as per-service operations, administration andmaintenance (OAM).
The components o the Alcatel-Lucent IP/MPLS inrastructure, which extends MPLS capabilitiesrom the core to access, are based on and can include:
Alcatel-Lucent7750ServiceRouter(SR)
Alcatel-Lucent7705ServiceAggregationRouter(SAR)
Alcatel-Lucent7450EthernetServiceSwitch(ESS)
Alcatel-Lucent7210ServiceAccessSwitch(SAS)
Alcatel-LucentOmniSwitch6855HardenedLANSwitch(HLS)
Alcatel-Lucent5620ServiceAwareManager(SAM)
Alcatel-Lucent5650ControlPlaneAssuranceManager(CPAM)
These Alcatel-Lucent products support routing, switching and multiservice capabilities, enablingthe power utilities to support real-time applications across the ull extent o the network. The
Alcatel-Lucent IP/MPLS implementation includes non-stop routing and non-stop service capabilitiesthat provide unparalleled reliability.
The network and service administration o the Alcatel-Lucent IP/MPLS communications inrastructureishandledbytheindustry-leadingAlcatel-Lucent5620SAM,anintegratedapplicationthatcoversall aspects o element, network and service management on one platorm. It simplies the programmingand management o the network, including automating routine tasks, correlating alarms to problems,managing the assignment o end-to-end connections, and acilitating the introduction and administrationofnewservices,allthroughauser-friendlypoint-and-clickinterface.TheAlcatel-Lucent5620SAMcan also manage many o the other Alcatel-Lucent and third-party elements within the network.
ForIProutingmanagementcontrol,theAlcatel-Lucent5650CPAMoffersreal-timecontrolplane
visualization, proactive control plane surveillance, conguration, validation and diagnosis. It enablespower utilities to overlay Layer 2 and Layer 3 services, MPLS tunnels and various OAM traces onthe control plane map. This simplies problem resolution, reduces control plane conguration errors,and reduces troubleshooting time.
The services enabled by the IP/MPLS communications inrastructure include, but are not limited to:
Teleprotection
SCADA
Voice(operationsandcorporate)
Mobileradio
Accesscontrol
Videoconferencing
WirelessIPdataaccesspointsforworkforcemobility
Alarmcircuits
Virtualprivatenetworks(VPNs)
Metering
IP-basedvideosurveillance
CorporateLAN/Internet
OperationsLAN
-
8/7/2019 March 2010 IP Comms for Smart Grid An
9/17
Reliable IP Communication for Smart Grids | Application Note6
Figure 2 shows an overview o the Alcatel-Lucent next-generation utility IP/MPLS communicationsinrastructure.
Figure 2. Alcatel-Lucent IP/MPLS communications infrastructure
The Alcatel-Lucent IP/MPLS communications inrastructure comprises an MPLS-based corenetwork that connects the control center (and backup center) with remote sites and substationswith a SONET/SDH-like reliability o sub-50 milliseconds recovery. At each substation, an IP/MPLSswitch/router aggregates trac rom applications such as IED/RTU or SCADA, WiFi access point,VoIP, corporate network access, access control, and video surveillance onto the core network orintra-substation or control center communications. In an Ethernet-centric implementation, the7210SASisusedtoaggregateEthernetandIPtrafcfromthevariousapplicationsbacktothecontrol center or to neighboring substations. For a substation with TDM connectivity requirements,the7705SAR,whilehandlingIPandEthernettrafc,canalsonativelysupportRTUserialinterfacesor SCADA, analog voice interaces or operations voice, and a T1/E1 connection rom a multiplexer.With this IP/MPLS network, trac is now packet-based, and bandwidth in the core networkis shared while QoS or critical trac is strictly maintained. Both IP and TDM services areconcurrently supported by the same IP/MPLS switch/router, reducing the overall number and costsoftelecomequipmentrequired.AsubstationLANcanbeimplementedwiththeOS6855-hardenedEthernet switch.
The network topology
A network topology is determined by the graphical mapping o 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
Control center
IP telephones
Ethernet
QoSn x T1/E1
Physicalsecurity
7210 SAS
GigE
Broadband IP traffic
Ethernet
n x T1/E1
Ethernet
n x T1/E1
OPS LANVideo
surveillance
3600
Substation SubstationSubstation
IEDs
IP telephones
TPR
IED
WiFiOPS voice
OS 6855
TPR
RTUs RTUs
5620 SAM
OPS LANVideo
surveillance
OS 6855
Videosurveillance
WiFiWiFi
QoS
7705 SAR
QoS
7705 SAR
7750 SR
-
8/7/2019 March 2010 IP Comms for Smart Grid An
10/17
Reliable IP Communication for Smart Grids | Application Note 7
Figure 3. Typical ring and partially-meshed architectures
A ring architecture provides an ecient, reliable environment as trac can be rerouted in theopposite direction o the ring, should a ailure occur. In a SONET/SDH application, every node istypically transmitting in both directions to provide end-to-end protection, eectively duplicatingall trac on the ring. In the Alcatel-Lucent IP/MPLS inrastructure, the network relies on theIP/MPLS ast reroute (FRR) eature or resiliency, which eliminates the requirement to duplicate thetrac on the ring. All the bandwidth can then be ully utilized and FRR ensures trac is reroutedin sub-50 milliseconds in the event o a node or link ailure in the ring, preserving all trac on thering. This topology is oten used in the aggregation part o the network and oers a very ecientway to aggregate and backhaul trac over a relatively low number o links.
Trac engineering is used to eciently carry the trac over the dierent meshed links across thecore o the network. A partially-meshed architecture uses more links and thereore provides morererouting alternatives. Partially-meshed networks are able to recover rom double aults and areoten deployed in the core o the network.
Microwave can be used to provide connectivity coverage to one or several sections o the network.An optical layer, Coarse Wavelength Division Multiplexing (CWDM) and Dense WavelengthDivision Multiplexing (DWDM), can also be used or increasing backbone network capacity.
TDM
Teleprotection Control center
CWDM/DWDM
7750 SR
7750 SR
7750 SR
7750 SR
7450 ESS
7450 ESS
Networkmanagement
SCADA
SecurityEMS/DMS
LAN
7705 SAR7705 SAR
7705SAR
7210 SAS
7210 SAS
7210 SAS
SCADA
OS 6855
OS 6855
TDM
7705 SAR
7705 SAR
7705 SAR
Teleprotection
CCTV
5620 SAM
-
8/7/2019 March 2010 IP Comms for Smart Grid An
11/17
Reliable IP Communication for Smart Grids | Application Note8
CAPEX/OPEX and scalability
To meet utilities growing requirements in terms o service deployment and bandwidth, theAlcatel-Lucent IP/MPLS communications inrastructure is extremely scalable, with the bandwidthin each ring able to scale up or down independently, according to changing requirements. TheIP/MPLS network can accommodate a growing number o applications and services. The granularity inMPLS bandwidth, scaling options and statistical multiplexing results in minimal CAPEX requirements todeploy and scale this inrastructure. The converged architecture and the ease o Ethernet technology
allow or optimized OPEX. A converged network also reduces the number o network elementsrequired, thus reducing costs.
Multiservice support
The Alcatel-Lucent IP/MPLS communications inrastructure oers a fexible network and serviceenvironment that enables the continuing support o existing services while incorporating newIP-based applications. The IP-based applications are typically more ecient in terms o bandwidthusage when deployed over an IP/MPLS inrastructure. All services converge at the access o thenetwork, where the required MPLS packet handling, such as encapsulation and QoS capabilitiesare executed. Dierent applications are transported via dedicated VPNs in a point-to-point,point-to-multipoint or multipoint-to-multipoint manner. The network also supports the migrationo the TDM-based services on to the IP/MPLS inrastructure.
Circuit Emulation Service over MPLS
Utilities need to consider how to leverage new IP/MPLS network technologies when migratinglegacy TDM systems and services. Utilities can take advantage o the IP/MPLS Circuit EmulationService (CES) unctionality and transition their legacy applications gradually. CES delivers thesame quality o experience as the existing TDM network inrastructure, with the same level opredictability. The Alcatel-Lucent IP/MPLS network has a circuit emulation interworking unctionthat ensures all inormation required by a TDM circuit is maintained across the packet network.This provides a ull transition to a packet network over time while providing TDM service continuity.
Two principal types o circuit emulation can be used: Circuit Emulation Service over Packet (CESoPSN)
and Structured Agnostic TDM over Packet (SAToP). CESoPSN allows NxDS0 service, includingull T1/E1 capability. SAToP provides the ability to carry unstructured T1/E1 circuits across theIP/MPLS network.
InanIP/MPLSnetwork,theMPLStunnelisusedasthetransportlayer(Figure4).APseudowire(PWE3)is created to identiy the specic TDM circuit within the MPLS tunnel. Circuit emulation interworkingunction ensures that all inormation required by the T1/E1 circuit is maintained across the packetnetwork. 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 of
packetization, latencyand jitter (to meet the
requirements forTDM services)
Pseudowiresidentify the specific
CES connection
MPLS tunnelstransport traffic
from point A to B
TDM
MPLS tunnel
CES IWF
TDM
-
8/7/2019 March 2010 IP Comms for Smart Grid An
12/17
Reliable IP Communication for Smart Grids | Application Note 9
Virtualization
The Alcatel-Lucent IP/MPLS communications inrastructure provides or the virtual isolation ovarious trac types on a single inrastructure. This allows the ull separation o trac rom dierentapplications or operations within the utility, allowing or a secure environment and eective bandwidthallocation. Advanced MPLS VPNs such as virtual private LAN service (VPLS) and IP virtualprivate networks (IP-VPNs) are supported which can be used to provide dierent applications oruser groups an environment that is private and unaected by other trac. One service is carried
across one VPN while the trac o dierent services is securely separated in their own VPN, eectivelyproviding separate private networks. Figure 5 shows the dierent VPNs that are supported on theAlcatel-Lucent IP/MPLS communications inrastructure.
Figure 5. MPLS-based VPN services
Layer 2 VPNs
Layer 2 VPNs include pseudowire and VPLS.
A pseudowire encapsulates trac over label switched paths (LSPs) to create a point-to-point service.An MPLS pseudowire is analogous to a private line within the MPLS inrastructure. It oers apoint-to-point connection between any two end devices. Figure 5.1. depicts three dierent types opseudowire TDM, ATM, and Ethernet. The pseudowire can be used or applications that requirededicated point-to-point connectivity such as supporting existing point-to-point TDM circuits orvoice or legacy SCADA RTUs.
VPLS service
Virtual bridge
2. Virtual Private LAN Services (VPLS)Layer 2 bridged multipointEthernet service
PE C
IP/MPLSnetwork
PE A
PE D
PE B
ATMservice
1. Pseudowire (PWE3)Point-to-pointconnections
PE C
IP/MPLSnetworkPE A
PE D
PE B
TDMservice
Ethernetservice
3. Layer 3 IP VPNRFC 4364 routed multipoint
PE DPE A
PE CPE B
Virtualrouter
R R
R
RR
IP/MPLS
network
VPRN
service 1
VPRN
service 2
R
B
B
B
B
B
B
B
-
8/7/2019 March 2010 IP Comms for Smart Grid An
13/17
Reliable IP Communication for Smart Grids | Application Note10
VPLS is another approach o a Layer 2 VPN. VPLS is a bridged multipoint service that orwardstrac based on the media access control (MAC) address. A VPLS service is protocol-independentand enables multipoint connectivity at Layer 2 within the MPLS inrastructure. Figure 5.2. depictstwo VPLS instances within a network. VPLS is composed o virtual bridges at each node. Eachvirtual bridge perorms 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 enddevices connected to the VPLS appear as i 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 specically or IP trac only. An IP-VPN is a routedservice that orwards trac based on the IP address. An IP-VPN enables multipoint connectivity atLayer 3 within the MPLS inrastructure (Figure 5.3.). With IP-VPNs, each MPLS node supports virtualrouting and orwarding (VRF) instances. An IP-VPN can be used to support multiple independentdepartmental networks with no routing table interactions among the dierent VRF instances.
Teleprotection over MPLS
Teleprotection systems monitor and compare conditions on transmission lines or coordinated trippingo transmission lines to quickly isolate aults in order to prevent damages to expensive substationequipment and instability in the power system. These systems rely on the communications networkor real-time status exchange between teleprotection relays (TPR). To ensure the power system isprotected, relay signals must be transerred with minimal latency.
The Alcatel-Lucent IP/MPLS network can support the stringent latency requirement or teleprotection.Setting up the right quality o service in an MPLS network will enable the network to discriminateamong various types o trac and advance higher priority protective relay trac over lower prioritytrac. An Alcatel-Lucent IP/MPLS network can manage protective relay trac fows to ensureperormance parameters like bandwidth, delay, and jitter are met. This minimizes the need to maintaina parallel TDM network or teleprotection.
Figure6showshowteleprotectioncanbesupportedbytheAlcatel-LucentIP/MPLSnetwork.TheinterfacefromtheteleprotectionrelaycanbeG.703,E&M,orRS-232.FortraditionalTDM-basedimplementation, these relay interaces are connected to a multiplexer or TPR signal transport via aT1/E1 and over SONET/SDH or microwave links to the next substation. With the migration to anIP/MPLSnetwork,anAlcatel-Lucent7705SARcanbeusedtosupportteleprotection.Forexample,relaysignalsviaRS-232orE&Mcanbeconnecteddirectlytothe7705SARforpseudowireconnectiontothefarend7705SAR.Alternatively,incaseswhereamultiplexeriscontinuingtobeused,aT1/E1fromthemultiplexercanbeterminatedontothe7705SAR.
-
8/7/2019 March 2010 IP Comms for Smart Grid An
14/17
Reliable IP Communication for Smart Grids | Application Note 11
Figure 6. Using an MPLS network for teleprotection
IEC68150standardforGenericObjectOrientedSubstationEvents(GOOSE)messagingoverEthernet was originally intended or intra-substation communications but is now being expanded to
includeinter-substationcommunications.ForthisEthernet-basedimplementation,the7705SARcan support protective relay trac over Ethernet with VPLS service.
Synchronous Ethernet
In most TDM networks, synchronization is distributed within the network using the SONET/SDHmechanisms built into the physical layer denition. To deliver the TDM service via a packet network,the same synchronization must be achieved through other means. Some TDM applications requirestratum-level clocking and distribution o inormation with very stringent accuracy. Utilities arelooking to migrate their synchronization inrastructures to a amiliar and manageable model. To enablerapid migration o these networks, synchronous Ethernet may be the easiest and quickest way toachieve (requency) synchronization and to allow the benets o an Ethernet network inrastructureto 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 roma high-quality requency reerence via the physical Ethernet interaces. This does not aect theoperation o any o the Ethernet layers and is transparent to them. The receiver at the ar end othe link locks onto the physical layer clock o the received signal, and thus itsel gains access to ahighly accurate and stable requency reerence. Then, in a way similar to conventional hierarchicalmaster-slave network synchronization, this receiver locks the transmission clock o its other portsto the requency reerence and a ully synchronous network is established. The implementationo Synchronous Ethernet will allow a utility to graceully integrate its existing systems and uturedeployments into a conventional industry-standard synchronization hierarchy. The Alcatel-LucentIP/MPLS products support Synchronous Ethernet, which has proven to out-perorm the standardsrequirements used by SONET/SDH, allowing migration rom SONET/SDH to a ull IP/MPLS networkas desired.
7750 SR
kV
t
MUX
G.703
T1/E1
E&M
RS-232
Ethernet
7705 SAR
Substation
TPR
7750 SR
MUX
G.703
T1/E1
E&M
RS-232
Ethernet
7705 SAR
Substation
TPR
IP/MPLS
-
8/7/2019 March 2010 IP Comms for Smart Grid An
15/17
Reliable IP Communication for Smart Grids | Application Note12
High Availability through MPLS
With the Alcatel-Lucent IP/MPLS communications inrastructure, utilities have the necessaryreliability level to maintain uninterrupted operations. Network resiliency is achieved by means othe end-to-end restoration capabilities o the MPLS FRR eature. The MPLS FRR eature enablesthe network to reroute connections around a ailure in less than 50 milliseconds. Because the networkis service aware, FRR can distinguish and prioritize trac redirection according to priority. To protectthe network against node or interconnection ailures, end-to-end standby MPLS paths are provisioned.
The Alcatel-Lucent MPLS implementation includes the unique additional High Availability eatureso non-stop routing and non-stop services. The benets are unparalleled availability and reliability:
Non-stoprouting ensures that a control card ailure has no service impact. Label DistributionProtocol (LDP) adjacencies, sessions and the database remain intact i there is a switchover.
Non-stopservice ensures that VPN services are not aected when there is a Control FabricModule switchover.
Quality of Service
In a utility environment where multiple services converge over a common inrastructure, QoS isessential. The Alcatel-Lucent IP/MPLS communications inrastructure enables the network to
discriminate among various types o trac, based on a rich set o classication attributes (includingMACaddress,IEEE802.1p,andIPaddresses)andprioritizetransmissionofhigherprioritytrafcover lower priority. The Alcatel-Lucent hierarchical quality o service (H-QoS) implementation alsoallows lower priority trac to burst in order to ll available bandwidth when higher priority applicationsgo idle. H-QoS uses an advanced scheduling mechanism to implement service hierarchies. Thesehierarchies provide maximum isolation and airness across dierent trac while optimizing uplinkutilization. With multiple levels and instances o shaping, queuing and priority scheduling, theAlcatel-Lucent IP/MPLS network can manage trac fows to ensure that perormance parameters(such as bandwidth, delay and jitter) or each application are met.
Effective management for easier day-to-day operations
A key element o reliable and fexible MPLS communications inrastructure is a set o eective,
simplied management tools that provide easy conguration and control o the network, eectiveproblem isolation and resolution, and support o new management applications. The Alcatel-LucentIP/MPLS network supports OAM tools that simpliy the deployment and day-to-day operation oa utility communications network. For example, service tests, interace tests and tunnel tests allowor rapid troubleshooting and enable proactive awareness o the state o trac fows to help minimizeservice downtime.
The Alcatel-Lucent IP/MPLS network is ully managed by the industry-leading Alcatel-Lucent5620ServiceAwareManager,whichautomatesandsimpliesoperationsmanagementonaconvergedMPLS network, driving network operations to a new level o eciency. The Alcatel-Lucent5650ControlPlaneAssuranceManagerprovidessimplieddiagnosisandintuitivevisualizationofthe relationship between services, the MPLS inrastructure and the routing plane.
-
8/7/2019 March 2010 IP Comms for Smart Grid An
16/17
Reliable IP Communication for Smart Grids | Application Note 13
Conclusion
Utilities are experienced at building and operating reliable and eective networks to ensure thedelivery o essential inormation and maintain fawless service delivery. The Alcatel-Lucent IP/MPLScommunications inrastructure can enable a utility to extend and enhance its network with newtechnologies like IP, Ethernet and MPLS. These new technologies will enable the utility to optimizeits network in order to reduce both CAPEX and OPEX without jeopardizing reliability. Advanced
technologies also allow the introduction o new Smart Grid applications that can improve operationaland workfow eciency within the utility. Alcatel-Lucent leverages cutting edge technologies, alongwith the companys 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 SwitchFRR 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
-
8/7/2019 March 2010 IP Comms for Smart Grid An
17/17
www.alcatel-lucent.com Alcatel, Lucent, Alcatel-Lucent and the Alcatel-Lucent logoare trademarks of Alcatel-Lucent. All other trademarks are the property of their respective owners.The information presented is subject to change without notice. Alcatel-Lucent assumes no responsibilityfor inaccuracies contained herein. Copyright 2010 Alcatel-Lucent. All rights reserved.CPG2896100117 (02)
top related