Overview of RSVPTE Network Simulator:

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• Overview of RSVP-TE Network Simulator
• Design and Implementation
• D.Adami, C.Callegari, S.Giordano,
• F.Mustacchio, M.Pagano, F.Vitucci
• Dipartimento di Ingegneria dellInformazione
• Elettronica, Informatica, Telecomunicazioni
• Università di Pisa

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Outline

• Motivations and Requirements
• a MPLS Node Simulator (MNS) based on the
  Constrained Routing Label Distribution Protocol
  (CR-LDP) is available in NS2 but..
• MPLS node implementation
• strict distinction between control and data
  plane
• RSVP-TE\ns module
• RSVP-TE enhancements for LSP handling
• simulator functions
• Functional validation test

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Motivations

• A MPLS Network Simulator (MNS) is available in
  the Network Simulator 2 (NS2)
• developed at Chungnam National University, Korea
• based on the Constrained Routing Label
  Distribution Protocol (CR-LDP)
• But
• IETF RFC 3468 states
• Multiprotocol Label Switching (MPLS) Working
  Group within the IETF focus its efforts on
  Resource Reservation Protocol (RSVP)-TE
  Extensions to RSVP for Label-Switched Paths (LSP)
  Tunnels (RFC 3209) as the MPLS signalling
  protocol for traffic engineering applications and
  undertake no new efforts relating to
  Constraint-Based LSP Setup using Label
  Distribution Protocol (LDP) (RFC 3212).
• CCAMP Working Group survey
• A survey of GMPLS implementations was published
  in June 2002. It includes responses from 22
  different implementers. Twenty-one of 22
  implementations include the GMPLS signalling
  based on RSVP-TE while only 3 include signalling
  based on CR-LDP.

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Motivations

• RSVP-TE Network Simulator will be useful to
  assess the feasibility of innovative mechanisms
  in different network scenarios
• MPLS networks (MPLS Working Group)
• Encoding of Attributes for Multiprotocol Label
  Switching (MPLS) Label Switched Path (LSP)
  Establishment Using RSVP-TE
• Extensions to RSVP-TE for Point to Multipoint TE
  LSPs
• DiffServ-aware MPLS networks (MPLS Working Group)
• RFC 3568 defines the concept of Classtype but no
  RSVP-TE enhancements have been standardized yet
  to support such an information
• GMPLS networks (CCAMP Working Group)
• RSVP-TE Extensions in support of End-to-End
  Generalized Multi-Protocol Label Switching
  (GMPLS)-based Recovery

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Requirements

• Overall design requirements
• Standard compliance with respect to IETF
  Standardization documents (e.g RSVP-TE RFC 3209)
• Extensibility enhancements in the signalling
  protocol and in the control plane mechanisms
  should be easily introduced in the simulator
• Modularity it should be possible to combine
  different modules implementing distinct
  functionalities (e.g. use of different scheduling
  algorithms)
• Open source code Network Simulator version 2

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MPLS node implementation

• To develop a full comprehensive simulation
  environment for MPLS networks the following
  functionalities are required
• Data plane mechanisms (label swapping, traffic
  mapping, etc.)
• Control plane mechanisms (MPLS signalling
  protocol RSVP-TE o CR-LDP)

Label Switched Path (LSP) 1
Label Switched Path (LSP) 2
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MPLS node implementation in the NS2 simulator
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MPLS node implementation control plane
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MPLS node implementation data plane
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RSVP-TE\ns module

• RSVP-TE object added or modified in the PATH
  message
• SESSION
• LABEL_REQUEST
• SENDER_TEMPLATE
• SENDER_TSPEC
• EXPLICIT ROUTE OBJECT (ERO)
• RECORD ROUTE OBJECT (RRO)
• SESSION_ATTRIBUTE

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RSVP-TE\ns module

• RSVP-TE object added or modified in the PATH
  message
• SESSION
• LABEL_REQUEST
• SENDER_TEMPLATE
• SENDER_TSPEC
• EXPLICIT ROUTE OBJECT (ERO)
• RECORD ROUTE OBJECT (RRO)
• SESSION_ATTRIBUTE

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RSVP-TE\ns module

• RSVP-TE object added or modified in the RESV
  message
• SESSION
• FLOW_SPEC
• FILTER_SPEC
• STYLE
• LABEL
• RECORD ROUTE OBJECT (RRO)

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Simulator functions

• LSP establishment
• Commands
• ltIngress-LERgt create-erlsp-rsvpte ltEgress-LERgt
  ltsessionIDgt ltFlowIDgt ltTunnelIDgt ltergt
• ltIngress-LERgt create-erbwlsp-rsvpte ltEgress-LERgt
  ltsessionIDgt ltFlowIDgt ltTunnelIDgt ltrategt ltbucketgt
  ltttlgt ltergt
• Action
• a PATH message is sent by the Ingress Label Edge
  Router (LER) towards the Egress LER
• An explicit route could be specified by means of
  the ERO Object
• After the Egress LER receives the PATH message, a
  RESV message is sent upstream
• The RESV message is processed by each Label
  Switched Router (LSR) along the path, which, in
  turn, performs label allocation and optionally
  resource reservation

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Simulator functions

• Mapping traffic flows to a LSP
• Command
• ltIngress-LERgt bind-flow-LSP ltDest Addressgt
  ltFlowIDgt ltTunnelIDgt
• Action
• Traffic flow is mapped onto the LSP
• LSP release
• Command
• ltIngress-LERgt release-LSP ltSessionIDgt ltFlowIDgt
• Action
• a PATH_ERR message is sent by the Ingress Label
  Edge Router (LER) towards the Egress LER
• labels and resources are released along the PATH

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Simulator functions

• Failure handling
• Command
• ltUpstream nodegt break-link ltDownstream nodegt
• Action
• a PATH_ERR message is sent by the LSR (Upstream
  node) towards the Ingress LER for each LSP
• In turn, the Ingress LER sends a PATH_TEAR
  message to release resources
• a RESV_ERR message is sent by the LSR (Upstream
  node) towards the Egress LER for each LSP
• In turn, the Egress LER sends the corresponding
  RESV_TEAR message to release resources

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Functional validation test

• Objective
• to assess LSP establishment, flow mapping and
  failure handling in the RSVP-TE Network Simulator
  

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Functional validation test

• Objective
• to assess LSP establishment, resource allocation,
  traffic engineering mechanisms and flow mapping
  in the RSVP-TE Network Simulator

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Functional validation test (NAM animation)
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Conclusions

• A full comprehensive MPLS network simulation
  environment based on the RSVP-TE signalling
  protocol has been developed
• Thank to its modularity and extensibility this
  simulation environment could be useful to
  speed-up the design, development and deployment
  of enhanced (G)MPLS networks
• The software is available on the TlcNetGroup
  software repository at the site
  wwwtlc.iet.unipi.it

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• Questions?
• Thank you