As shown, the pre-aggregated flow (1) (2) is forwarded as one input to the next stage. Flow (5) (6) has been terminated and distributed in two different directions. The ELS1000S card is able to aggregate any mixture of Ethernet and SDH aggregation. When the external Ethernet ports of an ELS1000S card are not used the term 'Blind Card' is used.
The SDH Traffic domain is used to configure cross connections between Lines, tribs and ELS1000 unit. The card based domain is used for configuration of the hardware, inspection of alarms, maintenance etc. The embedded domain is used to set allocate and configure the Ethernet domain circuits.
Provides :- Layer 2 aggregation/segregation Traffic management functions Bridging Maximum flexibility :- Flexible programmable data path (classification) Support of future protocols or changes in protocols by software update e.g. upgrade of release 1 to bridging Flexibility needed when standards evolve, e.g. OAM ITU, IEEE 802.1ad (provider bridges) Sophisticated traffic management features :- Policing, buffer management, queuing, scheduling QoS per flow; superior compared to pure packet switches
The ELS-1000S allows the flexible cross-connection from one interface towards another interface. Note: An interface can either be a physical interface like an Ethernet port (1 – 6) or an SDH transport channel (SDH TC) (1 – 24).
Virtual Packet Link (VPL) A VPL identifies a flow of Ethernet frames between two frame switching functions. Virtual Packet Channel (VPC) A VPC is the name for an end-to-end flow of packets over a logical or physical interface, e.g. an SDH VCG. VPCs are transmitted on aggregated interfaces. Multiple VPCs are transported and are differentiated by a VPC Identifier (VPCI).
SFP slot Logical configuration of slots with expected SFP module type Physical configuration of slots with equipped SFP module type Ethernet Port Interface speed, loopbacks Auto-negotiation parameters PAUSE parameters Ethernet Layer Aggregation (ELA) Logical Interface Aggregated Ethernet ports ELA parameters SDH TC Interface speed, loopbacks Encapsulation format Virtual Concatenation group (VCG) Concatenation type VC allocation to VCG LCAS parameters
To ensure QoS for all VPCs it is necessary to control the traffic which enters the network. Therefore, each VPC user has a traffic contract which defines the traffic source characteristic. Policing enforces the conformance of the arriving traffic with the traffic contract. Non-conforming packets are either dropped, marked with another internal discarding tag, or dropped so that the traffic stream which passes into the network is conforming to the traffic contract. The connection to external equipment is via Ethernet interfaces via a connector at the front of the equipment. The data flow comes in from Ethernet port is policed and leaves the card by a SDH TC port or by a second Ethernet port. This function enables the policing of traffic which belongs to a single flow of Ethernet packets i.e. a VPL, on a per Ethernet packet flow basis. it is also possible to police the traffic of multiple VPLs by a single traffic policing instance.
Committed Information Rate CIR This is the information rate at which data for a VPC is delivered on the ingress access links, trunk links and egress access links. CIR is measured in bits/s. CIR is a configured value. On the ingress access link it may be monitored (policing), in the trunk link this rate is adjusted in the rate limiter. Committed Burst Size Bc ( or Maximum Burst Size MBS) This is the amount of data that the VPC can definitely carry during a time period Tc. A major restriction for this value originates from packet buffer size restrictions. CIR is a configured value. Bc is measured in bits. Peak Information Rate PIR This is the absolute maximum information rate a VPC may tolerate. Data arriving at rates above CIR and PIR is handled as best effort, which mean that there is no guarantee for delivery and no guarantees for delay. PIR is configured. Peak Burst Size PBS This is the maximum amount of data the VPC can attempt to deliver during a time period Tc, exceeding PIR.
Buffer management and queuing is implemented in the traffic queue. The arriving data rate for a traffic queue may exceed (temporarily or continuously) the serving rate. In that case it is necessary to buffer those frames until they can be served. Queue discard frames based on colour attached at policer Buffer Management Types are Tail Drop or WRED There is a single service queue per interface (Ethernet port or SDH TC). All VPLs on a particular interface must use this queue. It is not possible to assign the same ID value to VPLs which are located on different interfaces. Each traffic queue supports 8 CoS queues which can be used by the customer to differentiate services (e.g. TDM service, Services with Assured Rate, Best effort service). The priority demultiplexer defines into which queue to insert a packet using the internal CoS tag. The internal CoS tag is assigned during classification.
The above diagram shows :- Ethernet port 2 (set at 10M) is connected to SDH-TC number 3. VC group 3 (is associated with SDH-TC 3), and is allocated VC numbers 6-10. 5 x VC-12s, ports 6-10 (10M), cross connections are made in the SDH domain.
Provision is made to set the number of STM–1 interfaces to the SMA’s switch plane which the ELS1000 card is allowed to use. (Section-02, equipment overview) Notes :- The card can be configured to use any number of STM–1s between one and the maximum permitted by the shelf type, slot and card limitations. If the shelf has more than one ELS1000S or another system card, the STM–1s are shared between the cards. Each of these cards must be allocated at least one STM–1. A maximum of four system cards (in any combination) i.e. ELS1000S, PacketSpan, CellSpan or P–Switch can be fitted into a SMA. The menu item Bandwidth Allocation is only visible when the card is used in a slot supporting multiple STM-1s.
Ethernet over SDH
2Multi-Service Platform Ability to handle SDH, PDH, SAN,Ethernet & WDM on a common platformfor efficient presentation, switching, aggregation & transport over NG-SDH Highly flexible 2M – STM64 TDM interfaces Full non-blocking VC-12 Switching 20G (128x128STM-1)- 60G (384x384 x STM-1) Flexible “Any port in Any slot” type Architecture Data bus enables the SMA16-64 as data centric hub Highest Port density to reduce costs Use of SFP technology to increase flexibility and reduce costsVirtual Private LANVirtual Private LANInternet AccessInternet AccessEthernet Leased LineEthernet Leased LineStorage Area NetworkStorage Area NetworkLegacy TDM ServicesLegacy TDM ServicesSingle MSP PlatformSingle MSP PlatformOptical Network
3Flexible Mapping BenefitsLCAS (Link Capacity Adjustment Scheme) Variation of the link capacity in units ofVC12, VC3 or VC4, as appropriate Ability to ‘re-use’ protection bandwidthGFP (Generic Framing Procedure) Support for multiple protocol traffic Standardisation provides componentcost savingsTrafficRateEthernetAggregateNxVCasrequiredBandwidthVirtual concatenation Allows more granularity for networkefficiency Delivers Ethernet services flexiblywithout the need to upgradeintermediate nodes Diverse routing means more efficientuse of bandwidth
4SDH MUX40Mbit/s40Mbit/s40Mbit/sUsing LCAS on unprotected linksSDH MUX20Mbit/s20Mbit/s20Mbit/s
5ATMIPServicesVoice DataSONET/SDHWDMFibreMPLSOptical Data Unit (ODU)Frame RelayGFPEthernetSANGFP enables us to map Ethernet Frames into SDHVirtual ContainersEoSDHGFP, LCAS & VCAT An Ethernet framecan consist of multiple IP packetsGFPVC
66Mbit/sLANFlexible assignment of link bandwidthusing Virtual ConcatenationTrafficRateEthernetAggregateNxVCasrequiredBandwidthVCAT assigns the bandwidth efficientlyEthernetSpeed10/100/1000Mbit/s6Mbit/sCustomerBandwidth6Mbit/sLANGFPSDHallocationVC-12VC-12VC-126Mbit/sNetworkVC-12VC-12VC-12VC-12VC-12VC-12EoSDHGFP, LCAS & VCAT
7CustomerBandwidth6Mbit/sLAN6Mbit/sLANEthernetSpeed10/100/1000Mbit/s6Mbit/sGFPSDHallocationVC-12VC-12VC-126Mbit/sNetworkVC-12VC-12VC-12VC-12VC-12VC-12EoSDHGFP, LCAS & VCATFlexible adjustment of linkbandwidth - in service, using LCASWeek 1 Week 2 Week 3 Week 4Provisioned6Mbit EthernetServiceScheduled additional4Mbit 10MbitEthernet ServiceLCAS allows for the flexible adjustment (addition orremoval) of provisioned bandwidthCustomerwants extra2Mbit/sVC-12Extra capacityadded to linkVC-128Mbit/s
9L2 Aggregation Card Provides point-to-multipoint functionality Acts as hub or ‘switch’ for PacketSpan customer located products Introduces new services when the market is ready Provides functionality from the core, not from every box in the deployment -lowers cost throughout, especially when upgrades are needed Dramatically reduces the cost of interfaces on SDH & data side Single tributary card much cheaper than overlay equipment, no newtraining/personnel or NMS needed Standard GFP, Virtual Concatenation (with LCAS and HO/LO SDH support) QoS options (committed rate, best effort etc) allowing differentiated & prioritisedservices Layer 2 Aggregation tributary card 2 port GigE, 4 port FastE trib card for SMA Series 1.2, 3, 4 & MSH11CP,C,41C, 51C & 64 (STM-16 version also for MSH51C/64) 2 port GigE, 16 port FastE trib card for OMS1664 8 Fast/GigE port layer 2 trib card for OMS3240/50
22The ELS1000S card is considered to have three logicaldomains:• SDH Traffic Domain of the PacketSpan card.Logical Domains• Card Based Domain, i.e. basic hardware/softwareoperation,including maintenance schemes.• Embedded (Ethernet) Domain.
23ELS 1000S - Overview Block DiagramTDMswitchTDMswitchPHYPHYFramer(GFP,VCG, LCAS)Framer(GFP,VCG, LCAS)SDHlineSDHlineGIGEFEELS 1000SPacketSwitchingEnginePacketSwitchingEngineSMAFunction already available on PacketSpan productsFunction already available on PacketSpan productsNew functionality of layer 2 cardNew functionality of layer 2 card
28ELS-1000S Traffic FlowSFP Slot Ethernet Port SDH TC VCGVCVCPQVPLPQVPL traffic enters card and is classified as required by VPL configuration classified frames are handled by policerSLA conformance is verifiedframes are internally tagged (“green, yellow, red”) and optionally discarded frames are cross-connected to egress pathframe modification (e.g. add VLAN tag) is performed if requiredqueue handles frames according to configured buffer management traffic leaves card at egress interface
31The QueueVPLPolicerVPLQueueGREENONLYGREEN ANDYELLOWQueue SizeMax4Mbytes30%45%GREENYELLOW &RED∑ Of CBS at Policers
32TRIBLINE1123456ETHERNETPORTSSDHTCs124SDH Domain CrossConnections, Line cardto Trib card,5 x VC12s (6-10)Ethernet Domain Cross ConnectionEthernet port 2 to SDH-TC 3VC group 3,with VCs 6-10 allocated.Configuration3
33Connections - Bandwidth AllocationSwitchLINEETrib(s)LINEWSMASWITCHEthernet connectionsELS1000SRIGHT CLICK ON THE CARDThe bandwidth of eachcard is set as perrequirements, but mustadhere to the card and slotlimitations (see section 02)