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Introduction to the MEF

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					 Carrier Ethernet over HFC Networks

Advances in Ethernet OAM

            Fred Ellefson
       VP Business Development
            ADVA Optical

                                      1
Agenda

• Challenges of OAM

• Advances in OAM standards and plans

• OAM, Ethernet access and demarcation




                                    2
Carrier Ethernet Challenges


    What is holding service providers back from
     deploying Ethernet more aggressively?

                    16%
          Better alternative solutions


                                                          66%
          Performance monitoring/SLAs inadequate


                     18%
          Price
                              Source: Light Reading Webinar 2006




                                                                   3
Ethernet OAM Standards Overview
 Standards                               Ethernet OAM
   Body
    IEEE     • 802.3ah – EFM OAM
             • 802.1ag – CFM
             • 802.1aj - TPMR
             • 802.1AB – Discovery
             • 802.1ap – VLAN MIB
   MEF       • MEF 7– EMS-NMS Info Model
             • MEF 15– NE Management Req
             • MEF 17 - OAM Req & Framework
             • MEF 16 – Ethernet Local Management Interface
             • Performance Monitoring
    ITU      • Y.1730 – Ethernet OAM Req
             • Y.1731 – OAM Mechanisms
             • G.8031 – Protection
             • Y.17ethqos – QoS
             • Y.ethperf - Performance
   IETF      • RFC-2544 – Benchmarking Methodology for Network Interconnect Devices
             • RFC-2819 – Remote Monitoring (RMON Etherstats)


   TMF       • TMF814 – EMS to NMS Model




                                                                         4
 Ethernet OAM Layers



  Services               ITU Y.1731 and MEF




 Connectivity        IEEE 802.1ag, ITU and MEF




                     EFM         EoSDH        EoTDM
Transport/Link   (IEEE802.3ah)    (ITU)       (ITU)




                                                 5
   Ethernet OAM Standards Activities

               UNI                                                                                                            UNI

                                                      100FX                         Carrier NW                    100FX

          Cust.                              Media             Media     Provider                Provider Media            Media                              Cust.
                                            Convrtr           Convrtr      Edge                   Edge Convrtr            Convrtr                            Eqpmnt.
         Eqpmnt.
                                                                          Switch
               802.1aj demarcation device




                                                                                                                                802.1aj demarcation device
MEF &                                                             Service Layer OAM (UNI to UNI)
ITU Y.1731


IEEE 802.1ag,                                                           Connectivity Layer OAM
MEF & ITU Y.1731

                                              Access Link OAM                                            Access Link OAM
IEEE 802.3ah




                                                                                                                     6
Ethernet OAM Standards

     Services and
      Performance           Basic Connectivity         Transport/Link
   (ITU Y.1731/MEF)         (IEEE 802.1ag,ITU)         (802.3ah EFM)
Discovery                 Discovery              Discovery

Continuity check (keep    Continuity check       Remote failure indication:
alive)                                           Dying gasp, link fault &
                                                 critical event

Loopback (non-intrusive   Loopback               Remote, local loopback
and intrusive)
AIS/RDI/Test                                     Fault isolation

Link Trace                Link Trace             Performance monitoring
                                                 with threshold alarms
Performance management                           Status monitoring


                                                                   7
IEEE 802.3ah Ethernet in First Mile

 • EFM standard completed in mid 2004
    – First Ethernet OAM standard completed
 • Focused on point to point Ethernet link OAM
    – Does not propagate beyond the link
 • Discovery
 • Remote failure indication
    – Dying gasp, link fault & critical event
 • Remote loopback
 • Performance monitoring and threshold crossing alarms
 • Ethernet OAM shares BW with data payload
    – Utilizes a “slow” protocol limited to 10 packets per second
    – OAMPDUs identified by MAC address and Ethernet
      Length/Type/subtype field
    – Uses a protocol sub layer between physical and Data link layers

                                                             8
IEEE 802.1ag Connectivity Fault Management (CFM)

                           Service Provider

               Operator                             Operator

                      Customer End-to-End Metrics
                      Provider End-to-End Metrics

          Operator Metrics                       Operator Metrics
   • Partitions network into hierarchical administrative domains
       – Basic connectivity checking and troubleshooting across any
         domain, and across multiple domains at the same time
   •   Continuity checks – proactive service verification
   •   Loopbacks – layer 2 version similar to IP Ping
   •   Link trace – layer 2 version similar to Traceroute
   •   AIS – Alarm inhibit signal
   •   Work in process

                                                                 9
ITU Y.1731 EthOAM – Service Level OAM

 •   Builds on 802.1ag
 •   Discovery
 •   Continuity check (keep alive)
 •   Loopback (non-intrusive and intrusive)
     – Defect detection/localization
     – Performance verification
 • Link trace
 • AIS/RDI/Test – out of service verification
 • Performance management for SLA verification
     –   Frame loss
     –   Frame delay
     –   Frame delay variation
     –   Others (errored frame seconds, service status (up/down),
         frame throughput, etc.)



                                                          10
IEEE 802.1aj TPMR
  • IEEE 802.1aj Two-Port MAC Relay
     – Defines protocols for interactions carrier bridge and remote 2-
       port relay device that might be used for demarcation
     – Uses SNMP natively over Ethernet (no IP!)***
  • Configuration of remote parameters***
     – VLAN behavior
     – CoS and QoS characteristics of interfaces
     – Forwarding behavior (data and L2 protocols)
  • Status information between carrier and customer***
     – Utilizing IEEE 802.1ag
  • Covers configuration and status of all aspects of remote
    device IF the device is a simple two-port relay forwarder
     – Does not apply to bridges, routers, etc. which may also
       implement UNI or forwarding functionality
     – Mostly intended for CARRIER owned demarcation device
  • Work in process

   ***Tentatively

                                                               11
Management of Network Edge

                                                     UNI
                                                   MAC Device
             Carrier IP
             Network
                           PE       802.3ah OAM           CE
                                      MEF ELMI
                                    802.1aj TPMR

Multiple standards address how to manage the network edge
• 802.3ah OAM addresses how to manage physical from the PE
  to the MAC layer of the remote device
• MEF ELMI addresses how to manage the UNI of the remote
  device
• 802.1aj Two-Port MAC Relay addresses how to manage a
  potential customer demarcation device
Each protocol adds some unique functionality, and adds some
  overlap functionality with the other standards

                                                     12
Test/Monitoring Standards

• Metro Ethernet Forum (MEF)
   – Recommended key parameters for SLAs – MEF 10
   – Service availability, frames lost, frame delay, frame jitter
   – Defined the “what”, not the “how”
• RFC-2544
   – Out of service testing – followed by most test sets, some demarc
     devices
   – Frame loss, latency, throughput, back to back, reset
• Y.1731
   – Focused on end to end service (WAN)
• RFC-2819 - RMON Etherstats
   – Monitoring of local performance (e.g. node or LAN)




                                                                    13
Remote Monitoring (RMON) RFC-2819

• Remote monitoring (RMON) provides a frame work of related
  standards for performance monitoring
• Introduces concept of “probe” or “monitor”
   – Initially stand-alone, now integrated into many devices
   – Completed 2000
• RMON-1 (RFC-2819) is focused on link layer (layer 2)
  monitoring
• Local performance monitoring (vs. end to end)
• Collected on port and EVC (VLAN) basis
• Includes parameters such as: Packet counts, multi-cast pkts,
  CRC errors, pkt size, collisions, jabber, etc.
• RMON designed for enterprise LAN applications




                                                               14
 RFC-2544 Testing

Benchmarking Methodology for Network Interconnect Devices

 • Suite of tests for verifying Ethernet equipment
    – Now being used for Ethernet services
 • Test suite is made up of:
    –   Throughput
    –   Latency           MEF SLA parameters
    –   Frame loss
    –   Back to back
    –   Reset
 • Results generally presented in graphical form
    – Each test is performed multiple times with different frame sizes




                                                             15
  Access Starts with Demarcation

Customer UNI                                                                                      UNI Customer
  LAN                                         Carrier WAN Network                                           LAN
Network                                                                                                    Network

                           100FX                     Carrier NW                      100FX

   Customer     Media               Media Provider                     Provider Media         Media      Customer
   Equipment   Converter           Converter Edge                       Edge Converter       Converter   Equipment


                                                             UNI
                                         100FX       100BT         100BT

                                                         Demarcation
                                                           Device

                                Ethernet Demarcation
     •   Provides separation between carrier WAN and enterprise LAN
     •   Enables testing and monitoring of both LAN and WAN
     •   Analogous to a CSU/DSU in frame relay




                                                                                                 16
Ethernet demarcation devices
                                         Demarcation
                                            Point
                           Carrier Network             Customer Network

                     EoX                                10/100BT
Carrier Network
                                                                         Cust.
                               Ethernet Demarcation Device              Eqpmnt.
                                   NID, UNI + Transport
                                                           Customer Premise


  • Ethernet demarcation devices are a critical element for OAM, SLA
    verification and service definition
  • Three key functions for demarcation device:
      – Ethernet NID (Network Interface Device)
      – Ethernet Service UNI (User Network Interface)
      – Integrated first mile transport




                                                                   17
User Network Interface (UNI)

                                        10M                                  50M

                         EoX                                             10/100BT
Carrier Network
                                                                                         Customer
                                            User Network Interface         Equipment

                                                    (UNI)        Customer Premise
    •   User Network Interface (UNI) function must be at customer-carrier demarcation
        point
         –   Especially if access link requires rate limiting for transport or to support multiple
             services
    •   MEF based service definition (UNI) on port or Ethernet Virtual Circuit (EVC) basis
         –   CIR/EIR – Committed/Excess Information Rate
         –   CBS/EBS – Committed/Excess Burst Size
    •   Traffic classification/priority based on TOS/DSCP/802.1P/802.1Q/etc.
         –   Low latency handling of VoIP/video services
         –   Ethernet Virtual Circuit (EVC) or VLAN support
               • 802.1Q & Q-in-Q - Add, remove, swap and stacking of VLAN tags


                                                                                    18
Network Interface Device (NID or NTE)
                   Carrier visibility of                                Carrier visibility of
                    carrier network                                     customer network


                          EoX
Carrier Network                                                           10/100BT

                                                                                            Cust.
                                                     NID/NTE                               Eqpmnt.
                                  Link OAM
         Service/Connectivity OAM                                            Customer Premise

          •   NID or NTE required at customer handoff for OAM
               –     Analogous to smartjack, CSU/DSU or NTE for frame relay
          •   Link OAM (802.3ah) is necessary but not sufficient
               –     Performance monitoring and threshold crossing alarms
               –     Remote failure indication - Dying gasp, link fault & critical event
               –     Remote loopback (Port)
          •   Services/Connectivity OAM (802.1ag, ITU, MEF, etc.)
               –     SLA monitoring
               –     Continuity verification
               –     Service level loopback
               –     AIS/RDI or fault propagation
               –     Test head to generate test suites (RFC-2544)
               –     Cable integrity test for customer premise

                                                                                     19
  Discovery - EFM

                      Discovery
                         Msg
                       (Active)
                                                                10/100BT
Carrier Network
                             EoX                                                 Cust.
                                                  Demarcation                   Eqpmnt.
                                   Discovery        Device
                                   Response                        Customer Premise
                                   (Passive)
      •   Allows provider edge switch to determine the OAM capability of
          the remote demarcation device
           – 802.3 ah OAM support is “optional”
      •   If both ends support OAM, then the two ends exchange state and
          configuration
           –   Mode - active vs. passive
           –   OAMPDU size
           –   Identity
           –   Loopback support



                                                                           20
Remote Failure – Link Fault/Critical Event

                                             Demarcation
                                                Point
                            Link Fault
                               msg
Carrier Network       EoX
                                                              10/100BT

                                                                               Cust.
                                           Demarcation                        Eqpmnt.

                                             Device
                                                                  Customer Premise


   •   Link Fault – e.g. Loss of signal is detected by the receiver
        – Sent once per second
   •   Critical Event – Manufacturer specified failure e.g. hardware or software
       alarm
        – Sent immediately and continuously




                                                                         21
Remote Failure - Dying Gasp

                                     Demarcation
                                        Point

                           Dying Gasp
                              msg
Carrier Network   EoX                              10/100BT

                                                                    Cust.
                                   Demarcation                     Eqpmnt.

                                     Device
                                                       Customer Premise


  • Signals carrier that an unrecoverable local fault (e.g. power
    failure) has occurred
  • Sent immediately and continuously
  • Critical for both AC and DC powered customer premise located
    equipment


                                                              22
Ethernet AIS/RDI

            Report              Alarms
            Alarm             Suppressed
                     Insert
                      AIS




 • Used to suppress downstream alarms and
   eliminate alarm storms from a single failure
 • Commonly used in legacy services like SONET,
   TDM, frame relay, etc.



                                           23
Fault Propagation

                                     Demarcation
                                        Point
                                    Propagation


Carrier Network    EoX                                         10/100BT


                                                                                Cust.
                                   Demarcation                                 Eqpmnt.
          Link down
          AIS
                                     Device                        Customer Premise
          RX JABBER                                     Link down
          RFI                                           AIS
          DUP UNKNOWN                                   Do nothing

      •   Fault Propagation allows upstream link issues to propagate
          downstream
      •   Critical for end user applications that need visibility of network issues
           – E.g. Redundant routing protocols (HSRP)



                                                                          24
Cable Integrity Testing

                              Demarcation
                                 Point


                                                      Remote Fault
                  EoX                             10/100BT
Carrier Network
                                                                   Cust.
                            Demarcation                           Eqpmnt.

                              Device                  Customer Premise

  • Identifies opens, shorts and impedance problems with CAT-5
    cable on customer premise
  • Measures distance to cable fault
  • Addresses large percent of customer induced issues




                                                             25
  Ethernet Port Loopback/Test

                                                Test Head


                                                                                  Loopback
                   Test
                                         Test Pattern       Test Pattern
                   Head                                                                  10/100BT
Customer    Demarcation                   Carrier Network                  Demarcation          Customer
Equipment                                                                                      Equipment
              Device                                                         Device
       Customer Premise                                                       Customer Premise

   •    Port level testing is ideal for turn up and commissioning
            –   Eliminates truck rolls
   •    Works with central test head to perform RFC-2544 tests
            –   Measures performance (delay, dropped packets, throughput, etc.)
            –   Ideal for fault isolation and locating within carrier network
   •    Can also work with integrated test head for end-to-end (service level) RFC-2544
        verification
            –   Ideal for end-to-end SLA verification




                                                                                    26
 Selective (Non-Intrusive) Loopback

                                                                              Selective
                                                                              Loopback
                                         Customer Traffic
                    Test
                                         Test Pattern
                    Head                                                                  10/100BT
 Cust.                                                                                            Cust.
Eqpmnt.        Demarcation               Carrier Network                      Demarcation        Eqpmnt.
                 Device                                                         Device
               Customer Premise                                                   Customer Premise


   •      Selective loopback performed on VLAN or specific OAM frames (e.g. opcode: ETH_LB)
   •      Intrusively test of an individual EVC (VLAN) while remaining EVCs are in-service
   •      Also used for continuity check (802.1ag) and service assurance (Y.1731)
           –    Far-end test head executes test periodically on non-service affecting VLAN or OAM
                frame to verify end to end connectivity through entire network – similar to ping
           –    Can measure delay, throughput, dropped frames of end-to-end service – follows actual
                data path (LSP, etc.) of customer traffic




                                                                                     27
RMON RFC-2819

                                                       Visibility


                           Carrier Network               Customer Network

                    EoX                                    10/100BT
Carrier Network
                                                                            Cust.
                                         Demarcation                       Eqpmnt.

                                           Device

        •   Local performance monitoring
        •   Collected on port and EVC (VLAN) basis
             – From both sides of demarcation point
             – Includes parameters such as: Packet counts, multi-cast pkts, CRC
                errors, pkt size, collisions, jabber, etc.
        •   RMON designed for enterprise LAN applications – also need:
             – Discarded packets (out of SLA), average bit rate parameters,
                ingress vs. egress BW, etc.


                                                                      28
 SLA Verification

• End to end SLAs are critical for carrier grade Ethernet services
    – Service availability, frame delay, frame jitter and dropped frames
    – Both round trip and 1 way basis
• Standards provide tools for SLA measurement – 802.1ag, ITU Y.1731
• Emerging technology – Ethernet demarcation devices required to measure
  end to end SLAs


    10/100BT
                                               Carrier IP                            10/100BT

                                               Network
               Demarcation                                             Demarcation
Customer         Device                                                  Device      Customer
Premise                                                                               Premise
                             Link               Trunk          Link
                             Perf.              Perf.          Perf.

                                     End to End SLA Verification

                                                                            29
SLA Monitoring Techniques

   • Based on Continuity Check Messages (CCM) in
     802.1ag (CFM) and Y.1731
          – Sent 1/Second – Fault Management
          – Sent 10/Second – Performance Monitoring
          – Sent 300/Second – Protection Switching
   UNI                                                                 UNI

                                      Carrier IP
                EoX                                           EoX
                                      Network
                           Provider                Provider
 Demarcation                Edge                    Edge
   Device                                                           Demarcation
                                                                      Device
  CCM



         Frame Delay, Delay Variation, Frames Lost, Service Availability



                                                                     30
  Performance Management OS

                             – Complements SLA measurement by demarcation
                               devices
                             – Centralized tool for collecting performance monitoring
                               data and storing in a database
                             – Centrally stored data can be used for real-time reporting
                               or monthly reports
                             – Service-oriented Key Performance Indicators (KPIs)




    10/100BT
                                                                                   10/100BT
                                          Carrier IP
               Demarcation
                                          Network                    Demarcation
Customer         Device                                                Device      Customer
Premise                                                                             Premise
                                  End-to-end SLA verification



                                                                          31
  Demarcation For SLA Consistency
Customer
Location 1
                          Sophisticated QoS
                         VLAN based services               Customer
                       Monitoring on port & VLAN           Location 2
                          Detailed statistics


             GbE                                       100FX
                            Carrier IP                               Limited QoS
                            Network                            Simple port level services
                                                                Monitoring on port only
                                                                  Limited statistics
                                                                              Customer
                                      ADM          EoSONET
                      PE                                                      Location 3


                                                                        ADM 100BT


  •   Ethernet demarcation device provides SLA
      consistency regardless of transport technology                             100BT           100BT
        –    E.g. ADM made to look like optical Ethernet                   ADM        Demarcation
                                                                                        Device
                                                                              Ethernet Demarcation Device
                                                                                   Sophisticated QoS
                                                                                 VLAN based services
                                                                               Monitoring on port & VLAN
                                                                                   Detailed statistics

                                                                                            32
Demarcation For SLA Consistency
      Customer
      Location 1
                                                            Customer
                                                            Location 2
      Test
      Head
                    Media
    Demarcation    ConverterGbE
                                                                   Media
      Device                                               100FX Converter    Demarcation
                                                                                Device

                                    Carrier IP
                                    Network
                    PE                                                     Customer
                                         ADM     EoSONET                   Location 3

•   Ethernet demarcation device provides OAM                                  100BT          100BT
    capability for remote management                                 ADM           Demarcation
      –      Performance monitoring                                                  Device
      –      Remote failure indication
      –      Remote loopback
      –      Continuity testing
      –      Remote test head
      –      Cable integrity testing
      –      etc.



                                                                                        33
Demarcation Device Integration

                                            Demarc &    Demarc &
                                            transport     CPE




                   EoX                                         10/100BT
 Carrier Network
                                                                           Cust.
                               ADM,                                       Eqpmnt.
                            Modem or            Demarcation
                          Media converter
                                                  Device      Customer Premise




  OAM standard supports demarcation integration into a customer owned
switch or carrier owned transport device (ADM, modem or media converter)



                                                                   34
Wholesale Ethernet

                     Demarcation                             Demarcation
                     & visibility at                         & visibility at
                       hand-off                                hand-off                   Demarc owned
                        points                                  points                     by Carrier A
                                                                                          Customer
Customer                                          POP 2                                   Premise 2
Premise 1
                       Carrier A       Mgmnt                  Carrier B
                       Network                                Network
      Demarcation                              Demarcation                     Demarcation
        Device                                   Device                          Device
                    Carrier A                                 Carrier B
      UNI                                        NNI                           UNI
                                        End to End Service

  •    Demarcation devices at both NNI & UNI
  •    Carrier A has visibility through carrier B to customer premise
  •    Provides end to end and carrier domain SLA visibility
  •    Often results in cascaded wholesale and retail UNIs

       Best effort Ethernet is not enough in the wholesale market


                                                                                     35
Summary

• Ethernet OAM is a key challenge as Ethernet moves
  into a mass market service
• Ethernet OAM standards are in place to address
  most of the issues
• These new standards will drive new OAM capability
  into the customer premise demarcation point that
  can address most of the operational challenges
• Low Ethernet capex costs shifts profitability focus
  to OPEX, and Ethernet OAM is key to managing
  Ethernet service OPEX costs




                                             36
Carrier Ethernet over HFC Networks

         Thank You



                                     37

				
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