MPLST ffi MPLS Traffic engineering by ikn20172

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									            Ingénierie Conseils Services Télécommunications



                                                                                                                                          1


              /           g               p
           ITU/BDT Arab Regional Workshop on
          “MPLS Technologies and Applications”
                                                                                                   Cairo, july 2009


                               Traffic  i    i
                          MPLS T ffi engineering

                                                                                                             Jacques BAUDRON
                                                                                                                         iXTEL
                                                                                                                     July 2009
                                                                                                               jacques.baudron@ixtel.fr
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                   Contents
            Ingénierie Conseils Services Télécommunications



                                                                                                                                2


                                                                            Some points about Quality of Services           3
                                                                                                      Traffic engineering   8




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
            Ingénierie Conseils Services Télécommunications



                                                                                                                     3




                                                                                                   Some points about
                                                                                                   Quality of Services




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                   Quality of Services
            Ingénierie Conseils Services Télécommunications



                                                                                                                         4
      Why QoS ?
         • Three main constraints in order to be able to
           transport any traffic:
                  – Respect of the signal:
                           • same shape of the signal at ingress and egress
                  – Interactivity:
                           • delay is as short as possible
                  – Integrity:
                                k tl        l          ibl
                           • packet loss as low as possible

                          The aim is to get same
                          working condition as TDM
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                    Quality of Services
            Ingénierie Conseils Services Télécommunications



                                                                                                                          5
      Services
          Services                                             Shape                      Low delay        Packet
                                                              respect                                       loss
          Audio, Video
          straming
                                                                  xxx                                         x
          Telephony,
          videoconf ...
                                                                  xxx                              xxx        x

          Data                                                                                               xxx

          Gaming                                                                                   xxx       xx

          ...                                                      ...                             ...        ...
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                   Quality of Services
            Ingénierie Conseils Services Télécommunications



                                                                                                                         6
                               Main        for Q S
                             • M i reason f QoS
                               degradation

             Shape respect                                Delay variation



             Excessive delay                              Buffer, excessive
                                                          store & forward



             Packet loss                                  Excessive load
                                                          in router



ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                   Quality of Services
             Ingénierie Conseils Services Télécommunications



                                                                                                                         7
         How to deal with congestion ?

         •      Traffic Priority
         •      Differentiation / classification
         •      Bandwidth reservation
         •      Traffic shaping/policing
         •      Control admission
         •      Overdimensioning
         •      Efficient allocation of resources
         •      Traffic spreading
         •      ...
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
            Ingénierie Conseils Services Télécommunications



                                                                                                                   8




                                                                                                   Traffic  i    i
                                                                                                   T ffi engineering




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                   Traffic Engineering
            Ingénierie Conseils Services Télécommunications



                                                                                                                         9




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             10
          • IP routing: three steps for each packet
                   – Store the packet
                   – Compute the best path to destination
                   – Forward the packet to next router


                                                                     Route computation

                                                                       Packet stored
                                                                      Packet forwarded




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications

                                                                                                      Dest   Out

                                                                      Dest     Out
                                                                                                       A
                                                                                                       B
                                                                                                              2
                                                                                                              3
                                                                                                                   11
      IP routing                                                       A        4                      C      3
                                                                       B        1                      D      3
                                                                       C        2                      E      1
                                                                       D        3
                                                                       E        3




                                   Dest      Out
                                    A         1
                                    B         2
                                    C         3
                                    D         3
                                    E         3



                                                              Hello




                    Packet routing
                    Network building

ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                                           12
      Shortest Path First




          Problem: all the traffic between B                                           Solution: increase BE and EG cost
          and G take the shortest path =>
          Node E congested                                                             => Node A and node D congested



ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             13
      IP routing problems
                          • Path computation
                                   – Time
                                   – Processing power
                                   – For each packet in each node
                            Lack f imagination » f path
                          • L k of « i  i ti     for th
                            computation
                                   – Shortest path first

ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             14
      MPLS contribution for routing

                               is built      d t   i d
                       • MPLS i b ilt on pre-determined
                         paths
                                – Paths can be calculated in order to
                                  avoid hotspot: explicit routing
                                            p      p            g




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             15

                                       • MPLS routing: two steps
                                                – Ingress router chooses the best
                                                  LSP and insert the label
                                                – Intermediate router forward the
                                                  packet




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             16
      Vocabulary




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             17
      MPLS working
      process




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             18
      LSP setting




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             19
      LSP setting
                                       • Route calculation
                                                – How to find the route?
                                       • Signaling mechanisms
                                                – How to set the route in the
                                                  equipment?




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                                                  20
      LSP route calculation
                                                                                                   Off Line



                                                              Explicit
                                                                   t i tb    d
                                                              constraint based
                                                              routing

          LSP setting                                                                              On Line
                                                                                                      t i     l l t d by
                                                                                                   route is calculated b source


                                                                p
                                                              Implicit
                                                              hop by hop routing




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                                               21
          Information
          flooding




                                                                                                      Each LSR stores the
                                                                                                      information in Traffic
                                                                                                      Engineering Database


ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications


                                                            g
                    Calculation is performed once, at the ingress
                                                                                                                          22
      LSP route calculation
                        – Routing constraints
                                                              • Performance constraint
                                                                  – Minimum bandwidth
                                                                  – Maximum delay ...
                                                              • Administrative constraints
                                                                  – Path that excludes certain links in the network ...
                                                    – Information needed by source
                                                              • Trunk load
                                                              • Traffic demand (via SLA, measurement ...)
                                                    – Forwarding path description


     ⇒Result: list of Label Switching Routers (LSRs)
     Explicit Routed Object for RSVP-TE or Explicit Route for CR-LDP
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             23
      Signaling  Three mechanisms:
      mechanisms     – LDP (Label Distribution Protocol)
                                                              • Implicit routing
                                                              • Hop by hop label distribution
                                                              • No traffic engineering
                                                      CR-LDP
                                                    – CR LDP (Constraint based Routed Label Distribution
                                                      Protocol)
                                                              • Explicit routing
                                                              • Traffic Engineering
                                                              • Scalable
                                                    – RSVP-TE (Resource Reservation Protocol with Traffic
                                                        g         g         )
                                                      Engineering Extensions)
                                                    – Explicit routing
                                                              • End-to-end signaling
                                                              • LSRs maintain soft state
                                                              • Less scalable
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             24
         CR-LDP: Constraint
         based Routed Label
         Distribution Protocol




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             25
         CR-LDP: Constraint
         based Routed Label
         Distribution Protocol

                             Seven traffic parameters
                                       –     P kd
                                             Peak data rate (PDR)
                                       –     Peak burst size (PBS)
                                       –     Committed data rate (CDR)
                                       –     Committed burst size (CBS)
                                       –     Excess burst size (EBS)
                                       –     Frequency
                                       –     Weight
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                        Resources optimisation
            Ingénierie Conseils Services Télécommunications



                                                                                                             26
         RSVP-TE: Resource Reservation Protocol with
         Traffic Engineering Extensions




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                      Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                               27

                                       • Self healing networks switch traffic to
                                         spare resources in case of failure
                                       • Two ways:
                                                • Protection: both alternate path and
                                                  normal path are set up and
                                                  alternate path is in stand by mode.
                                                • Restoration: alternate path is
                                                  calculated after failure


ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                    Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                                                28
                                                                                                   Proba OK entre A and B =
          Protection: Availability
                                                                                                     ( Proba OK Normal
                                                                                                       OR
                           Normal                                                                        (Proba Backup
                                                                                                       Proba OKOK Backup
                                                                                                       )
                                                                                                          AND
         A                                                             B                               AND
                                                                                                          Proba OK Monitoring
                                                                                                       Proba OK Switch
                                                                                                          AND
                           Backup                                                                          Proba OK CTRL
                                                                                                           )
                                                                                                       )
                                                                                                       AND
                                                                                                       Proba OK SWITCH

ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                                                  29
         Protection: SDH


                          125 µs



      The « signature » of
      each frame is                                                                                          The calculation is done
         l l t d d      t
      calculated and sent                                                                                       again at the output:
      in next frame.                                                                                                   SignatureOut
      SignatureIn




                          An alarm is raised if                                                                  y
                                                                                                   Detection delay is 3
                      SignatureIn ≠ SignatureOut                                                   frames: 375 µs
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                              Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                                              30
         Protection: SDH (SNCP)

                                                                                                              t    k h
                                                                                                      SDH network: when
                                                                                                      there is a failure,
                                                                                                      alarms are raised at
                                                                                                                      path.
                                                                                                      the end of the path


                                                                                                      When ends of path
                                                                                                      detect alarm, they
                                                                                                      switch on protection
                                                                                                      resource


            Protection delay has been arbitrarily fixed at 50 ms.



ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                      Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                               31
         Protection: Packet networks


                        • Two questions:
                                  – How long is it to detect failure ?
                                            • 100s µs ? 10s ms ? 100s ms ?
                                            => Failure detection from physical layer
                                  – How long is it to signal failure ?
                                            • 100s µs ? 10s ms ? 100s ms ?
                                            => Local repair

                          Delay is not deterministic

ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                      Resilience
            Ingénierie Conseils Services Télécommunications



  E h node send periodic messages
  Each d        d    i di                                                                                                        32
  (KeepAlive) to next node.


   The recommended
   period for KeepAlive
   is 5 ms…
        … but the current value
        is at least 1 second and
                often 3 secondes




                        An alarm is raised when                                                    Detection delay is > 1
                       there is a loss of message                                                  seconde
                                                                                                                         (   )
                                                                                                   Using transport layer (SDH)
                                                                                                   alarms allows lower
                                                                                                   detection delay
ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                                          Resilience
            Ingénierie Conseils Services Télécommunications




                                                                           Label 10                     Label 11                        Label 12
                                                                                                                                                         33


                                                                     R1                        R2                                  R3               R4




     MPLS Fast ReRoute (FRR)

         LSR R2, when detecting the                                                                                 R5
         failure, stacks label 11 and
         label 20.                                                          Label 10                     Label 11                        Label 12
                                                                                                                         R
                                                                                                                         5
                                                                      R1                           R2                               R3              R4
                                                                                               Label 20

                                                                                               Label 11


                                                                                                                             Label 11




                                                                                                                    R5




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                              Resilience
            Ingénierie Conseils Services Télécommunications



                                                                                                                             34
         Protection: Fast ReRoute

                                                                                                      When th
                                                                                                      Wh there is ai
                                                                                                      failure, alarms are
                                                                                                      raised at the end of
                                                                                                           trunk.
                                                                                                      the trunk
                                                                                                      When ends of trunk
                                                                                                      detect alarm, they
                                                                                                      switch on protection
                                                                                                      resource




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                 Resilience
            Ingénierie Conseils Services Télécommunications


            g      g
  Because signalling is done between the ends of
  the trunks and not between the ends of the                                                                                     35
  path, each trunk has its own protection



                                                                                                   Backup LSPs: LSPs are « hot
                                                                                                   stand by » resources.
                                                                                                   Bandwidth have to be
                                                                                                          d
                                                                                                   reserved
                                                                                                   MPLS Fast ReRoute requires
                                                                                                   extra bandwidth for local
                                                                                                   repair
                                                                                                     p




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                                Resilience
            Ingénierie Conseils Services Télécommunications




         F
         Fast ReRoute: l
              R R      local protection
                           l        i                                                                                    36
                                     NHOP path

  Link
  Protection
                                                                                   PLR:
                                                                                   PLR: Point of Local Repair


                                     NNHOP path

   Node
   Protection




  Element
  Protection


ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
                                                                                                      Resilience
            Ingénierie Conseils Services Télécommunications




         F
         Fast ReRoute: l
              R R      local protection
                           l        i                                                                          37




                                   • The idea
                                             – Get a fast protection in some 10s
                                               milliseconds,
                                             – Then rearrange traffic (restoration)
                                               in some seconds



ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com
            Ingénierie Conseils Services Télécommunications



                                                                                                      38




                                         Thanks for your attention !




ITU/BDT Arab Regional Workshop on“MPLS Technologies and Applications” - MPLS Traffic engineering
Jacques BAUDRON - iXTEL - 36, avenue d’ASSAS 78470 St Rémy lès Chevreuse France - www.retitools.com

								
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