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COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 1
IEEE 1588v2 PTP and Synchronous Ethernet: Synchronizing the Asynchronous
T-BERD®/MTS-6000A and 8000 MSAM Ordering Information
1588v2 PTP
– CTLS1588 (-U1) – IEEE 1588v2 PTP 10 Mbps to 1 Gbps test option
Synchronous Ethernet
– CTLSSYNCE (-U1) – SyncE 1G test option
– C10GSYNCE (-U1) – SyncE 10G test optionUse Case Turn-up and troubleshoot Ethernet networks using
synchronous timing standards
Intended Audience Carriers deploying, managing, and selling Ethernet Backhaul Services
• Designed for operations personnel who verify network synchronization, turn-up, fault analysis, and quality of service (QoS)
Carriers/NEMs designing and deploying network elements (NE) supporting TDM over IP services
• Designed for engineers and operations personnel involved with designing, installing, and troubleshooting TDM over IP services using Synchronous Ethernet and 1588v2 PTP technologies
Applications: Install, turn-up, troubleshoot, and ensure QoS on networks that support synchronous timing standards such as 1588v2 PTP and Synchronous Ethernet.
Solution DescriptionIEEE 1588v2 PTP is a test option for the T-BERD/MTS-6000A and 8000 Multi-Services Appllication MVodule (MSAM) that enables users to verify the connectivity, quality, and synchronization of networks using 1588v2 PTP. With this functionality, users can ensure proper network synchronization by emulating 1588v2 slave/master NEs and ensure network QoS by characterizing PTP messaging and packet delay variation (PDV) stability over time.
Synchronous Ethernet (SyncE) is a test option for the T-BERD/MTS-6000A and 8000 MSAM that provides real-time decodes of G.8264 sync status messages (SSM) on circuits up to 10 Gbps rates. With this feature, users can synchronize a circuit by verifying the propagation of the originating network clock source.
Value PropositionAs carriers continue to adopt carrier Ethernet, new standards such as Synchronous Ethernet and IEEE 1588v2 PTP have been developed to enable the high accuracy time synchronization of NEs, services, and networks. These new standards enable the successful transition of traditional TDM services to lower cost per bit Ethernet networks. Without synchronization, Ethernet networks cannot deliver services that require high accuracy synchronization, such as voice, video, and mobile backhaul. For example, mobile backhaul uses 1588v2 or SyncE to synchronize devices betweenthecellsiteandswitchingoffice.Withoutverifyingsynchronization,endusers may experience problems such as dropped calls or poor call quality.
The SyncE and 1588 test options on the T-BERD 6000A and 8000 MSAM helps users verify network synchronization, continuity, and quality of service. These advanced test options help solve issues associated with master/slave connectivity, synchronization stability, and continuity of the time synchronization chain.
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 2
Feature/Benefit Summary – 1588v2
Feature Description Advantage Benefit
Master/slave NE emulation
Emulate master/slave NEs through the support of 1588v2 PTP messaging
Verify NE connectivity, operation and provisioning
Enables users to sectionalize problems by isolating NEs with emulation capability
PTP frame link counts and stats
Measure and decode PTP messages on a circuit under test
Verify message connectivity and analyze diagnostic information in tables or graphs over time
Ensure that PTP messages are being routed correctly with end-to-end connectivity
Packet delay variation of PTP frames
Measure the packet delay variation associated with PTP handshaking between master/slave
Ensure high-accuracy time synchronization by measuring PDV (a.k.a. Jitter) on the sync source
Isolate problems associated with unstable network synchronization such as dropped calls
Supports multiple streams of data planetrafficandPTPmessages
Transmit up to four background trafficstreamsandPTP messages simultaneously
Ensure the prioritization of PTP messages versusdataplanetraffic
Ensure proper network synchronization under worst-case network load conditions
Capture and decode PTP messages
Perform deep packet inspection on PTP messages
Verify the correct handshaking of master and slave NEs
Resolve higher layer protocol issues with one instrument
Feature/Benefit Summary – SyncE
Feature Description Advantage Benefit
Measure SyncE frequency and offset
Measure the received frequency of the circuit under test; measure frequency offset from nominal in ppm
Verify proper frequency propagation throughout the SyncE network
Identify incorrect network operation and degraded QoS due to poor frequency synchronization
Test using recovered and external clock source references
Receiving and sourcing trafficrequiresrecovered or external clock synchronization by the test set
Test set frequency synchronization is mandatory in support of SyncE testing
Quickly test and verify proper SyncE network operation
Capture Ethernet Synchronization Messaging Channel (ESMC) messages
Capture ESMC messages at line rate for evaluation in Wireshark
Debug and verify potential issues associated with improper ESMC message content or formats
Identify network timing recovery issues quicker by evaluating ESMC communications
Sync Status Messages (SSM) decodes
Displays a decode of the timing source Quality Level (QL) driving the synchronization chain
Isolate issues associated with improperlyconfigurednetwork timing chains
Quickly identify issues associated with providing the incorrect reference clock to a NE
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 3
Use Case: Turn-up PTP Enabled Networks - 1588v2Networks such as 1588v2 PTP require that master/slave nodes establish time synchronization using 1588v2 PTP handshaking which occurs continuously on a constant basis and is required to maintain accurate synchronization. Failure to establish PTP message connectivity, makes achieving synchronization impossible and disables support for synchronized services. Technicians can use the T-BERD/MTS-6000A and 8000 MSAM to emulate slave/master NEs to verify the continuity and messaging across a 1588v2 network.
Master Slave
PTP Messaging
Announce
Sync
Follow_Up
Delay_Req
Delay_Resp
Use Case: Ensure Accurate Time Synchronization - 1588v2Time accuracy in a 1588v2 network relies on consistently received PTP messages betweenmaster/slaveelements.DataplanetrafficinanetworkcanaffectthetransitdelayofPTPmessagesbecausealltrafficsharesthesameNEprocessor.Therefore, a network with high utilization can affect the performance of end-to-end PTP messages and ultimately degrades synchronization. This issue can be identifiedbyperformingapacketdelayvariation(PDV)measurementonthePTPmessages exchanged between master and slave NEs. With the T-BERD/MTS 6000A and 8000 MSAM, users can verify the proper delivery of PTP messages by measuring PDV stability over time.
TDM Ethernet
PTP MessagingPrimary
ReferenceSource
MSAM -1588v2 Slave
Ethernet
Master
TDMCE IWF NTE NTEEthernet
Network
Sync Packet Delay Variation
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 4
Use Case: Troubleshooting of Connectivity - Perform Deep Packet Inspection – 1588v2During a 1588v2 network installation, PTP message connectivity problems can arise between the master and slave. Failure to establish PTP message connectivity makes achieving synchronization impossible and disables support for services. When troubleshooting these links, the T-BERD/MTS-6000A and 8000 MSAM can be used in Terminate mode to capture PTP messaging on both the transmit (Tx) and receive (Rx) test ports up to 1G. In this mode, the T-BERD/MTS-6000A and 8000 simultaneously generates, receives, and captures PTP messages on the circuit under test. Users can quickly identify higher layer protocol issues that may be associated with PTP messages and/or provisioning.
Use Case: Verify Link Quality in support of Accurate Timing - 1588v2Messagingwith1588/PTPisdesignedtoworkunderspecifiednetworkloadconditions. When NE processor utilization is high, it can affect PTP message processing and, therefore, forwarding. PDV in PTP messages will ultimately affect synchronization because it depends upon consistently timed message reception. TheT-BERD/MTS-6000Aand8000MSAMcanemulatedataplanetraffic(uptofour streams) and PTP messages simultaneously. Under these conditions, users can verify that 1588v2 PTP networks are operating properly under worst-case networkloadingscenariosandevenbeyondspecifiedlimits.
Stream #1Stream #2Stream #3Stream #4
PTP messages
Ethernet switchMaster
Slave
Sync PDV graph
PTP link counts/stats
Line rate capture of PTP messages
PTP decode with Wireshark
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 5
Use Case: Verify Network Reference Timing - Synchronous EthernetIn this scenario, the T-BERD/MTS-6000A MSAM is testing a Synchronous Ethernet circuit. The master clock (time reference) provides reference timing for the network, which ispropagatedthroughoutthenetworkviatheenhancedphysicallayerspecificationsofSyncEcircuits.Informationidentifyingthequalifylevel(QLmessage)ofthemasterclock driving the synchronization chain is passed through the network via sync status messages (SSM) in the Ethernet synchronization messaging channel (ESMC) that are contained in specialized Ethernet frames sent periodically, 1 per second. The T-BERD/MTS 6000A and 8000 MSAM enables users to verify that a SyncE circuit is correctly synchronized by decoding and displaying the SSM, capturing ESMC messages, and measuring the received frequency offset (ppm) of the circuit under test. In addition, duringEthernetserviceturn-up,testtrafficcanbegeneratedusinganexternalreferenceorrecoveredSyncEtimingtoensureproperSyncEtrafficpropagation.
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 6
Quick Demo Setup - 1588 PTP Link Stats, Link Counts, and Packet Delay VariationSelect the Layer 2 or 4 PTP/1588 term test for the intended interface. Select the PTP or graphs/major results category and the link stats/counts and graph to view results.
Quick Demo Setup - Ethernet Sync Status Messaging (E-SSM)SelectanyEthernetLayer2(orabove)application.WithintheEthernetmajorcategory,selecttheSSMresultscategorytoviewSSMresults.Receivedtrafficfrequencyoffsetislocatedatthetopofthescreen,whiletraffictimingsourceislocatedonthebottomnexttothelaserbutton.
COMMUNICATIONS TEST & MEASUREMENT SOLUTIONS
WEBSITE: www.jdsu.com February 2011 7
FAQQ: How does the 1588v2 PTP functionality of the T-BERD/MTS 6000A and 8000 compare to the former JDSU CPO product the Calnex Paragon?
A:TheParagonismoreofalabtoolfocusedonNEdesignandverification.Anexample of this is support of the delay insertion function currently supported by theParagon.TheMSAMisfocusedonfieldoperationstaskedwithturningupandtroubleshooting 1588/SyncE networks.
Q: Can you perform one-way delay measurements between two tests using the 1588 protocol?
A: No, this feature is not currently supported, but it is under evaluation for a future release.
Q: Is this a software or hardware upgrade to existing units in the field?
A: Both features (SyncE and 1588v2) are software upgrades to existing units in the field.
Q: Are these features supported on the existing T-BERD/MTS 8000 transport module?
A: No, they are only supported on the MSAM for use with the T-BERD/MTS 8000 and 6000A.
Q: Are there pre-requisites for this feature?
A: Yes. Both of these options require Ethernet test interfaces. Keep in mind that the 1588v2 is supported up to 1 GigE rates, and Synchronous Ethernet is supported up to 10 GigE rates.
Q: Why would a provider deploy Synchronous Ethernet versus 1588v2?
A: Providers can deploy both technologies; in fact, some providers have expressed adesiretousebothtechnologiesonthesamenetworktorealizebenefitsfromboth.
Therefore, there are some fundamental differences between the technologies as follows.
• Synchronous Ethernet provides highly accurate frequency synchronization thatdependsontheenhancedphysicallayerspecificationsofSyncEcircuitsand, therefore, requires new NE hardware that can increase the overall cost of deployment.However,SyncEisnotaffectedbytheEthernet/IPtrafficloadingofanetwork.
• Primarily a software based-implementation, 1588v2 promises to decrease costs by working on existing carrier Ethernet networks. It also provides carriers a time ofday.However,oveeralltrafficloadingofthenetworkcanaffect1588v2PTPsynchronization accuracy.
Q: What are the similarities and differences of 1588v2 to the original 1588 version 1 protocol?
A: Version 1 of 1588 was originally developed for the synchronization of test equipment in LAN environments.