Transcript Overview of RSVP-TE Network Simulator: Design and

Overview of RSVP-TE Network Simulator:
Design and Implementation
D.Adami, C.Callegari, S.Giordano,
F.Mustacchio, M.Pagano, F.Vitucci
Dipartimento di Ingegneria dell’Informazione:
Elettronica, Informatica, Telecomunicazioni
Università di Pisa
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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 CRLDP)
Destination
Label Switched Path (LSP) 1
Label Switched Path (LSP) 2
Source
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
MPLS node implementation in the NS2 simulator
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
MPLS node implementation: control plane
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
MPLS node implementation: data plane
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
RSVP-TE\ns module
• RSVP-TE object added or modified in the PATH message:
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SESSION
LABEL_REQUEST
SENDER_TEMPLATE
SENDER_TSPEC
EXPLICIT ROUTE OBJECT (ERO)
RECORD ROUTE OBJECT (RRO)
SESSION_ATTRIBUTE
Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
RSVP-TE\ns module
• RSVP-TE object added or modified in the PATH message:
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SESSION
LABEL_REQUEST
SENDER_TEMPLATE
SENDER_TSPEC
EXPLICIT ROUTE OBJECT (ERO)
RECORD ROUTE OBJECT (RRO)
SESSION_ATTRIBUTE
Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
RSVP-TE\ns module
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RSVP-TE object added or modified in the RESV message:
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SESSION
FLOW_SPEC
FILTER_SPEC
STYLE
LABEL
RECORD ROUTE OBJECT (RRO)
Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Simulator functions
• LSP establishment
– Commands:
<Ingress-LER> create-erlsp-rsvpte <Egress-LER> <sessionID>
<FlowID> <TunnelID> <er>
<Ingress-LER> create-erbwlsp-rsvpte <Egress-LER> <sessionID>
<FlowID> <TunnelID> <rate> <bucket> <ttl> <er>
– 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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Simulator functions
• Mapping traffic flows to a LSP:
– Command:
<Ingress-LER> bind-flow-LSP <Dest Address> <FlowID> <TunnelID>
– Action:
• Traffic flow is mapped onto the LSP
• LSP release:
– Command:
<Ingress-LER> release-LSP <SessionID> <FlowID>
– 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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Simulator functions
• Failure handling
– Command:
<Upstream node> break-link <Downstream node>
– 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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Functional validation test
• Objective
– to assess LSP establishment, flow mapping and failure
handling in the RSVP-TE Network Simulator
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Functional validation test (NAM animation)
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
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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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005
Questions?
Thank you
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Fabio Mustacchio - IPS-MOME 2005 – Warsaw, March 15th 2005