70 likes | 269 Views
PCECP Requirements and Protocol Extensions in Support of Global Concurrent Optimization <draft-lee-pce-global-concurrent-optimization-02.txt>. Young Lee (Huawei) J-L Le Roux (France Telecom) Daniel King (Aria Networks) Eiji Oki (NTT). Document Updates.
E N D
PCECP Requirements and Protocol Extensions in Support of Global Concurrent Optimization<draft-lee-pce-global-concurrent-optimization-02.txt> Young Lee (Huawei) J-L Le Roux (France Telecom) Daniel King (Aria Networks) Eiji Oki (NTT) 68th IETF – Prague, Czech Republic March 2007
Document Updates • J-L Le Roux added to co-author list • Global Concurrent Optimization (GCO) definition included (per J. Ash) • Requirements have been refined • Clarifications in relation to RFC4657 (per J. Ash) • New Requirements have been added • PCEP Protocol Extension works included in the new versions (01 and 02). 68th IETF – Prague, Czech Republic March 2007
GCO Definition Global Concurrent Optimization (GCO) is a concurrent path computation application where a set of TE paths are computed concurrently in order to efficiently utilize network resources. A GCO path computation is able to simultaneously consider the entire topology of the network and the complete set of existing LSPs, and their respective constraints, and look to optimize or re-optimize the entire network to satisfy all constraints for all LSPs. A GCO path computation can also provide an optimal way to migrate from an existing set of LSPs to a reoptimized set (Morphing Problem). 68th IETF – Prague, Czech Republic March 2007
Requirements Updates (Existing) • GCO path computation indicator • Global Objective Function (GOF) • "synchronized objective functions" in section 5.1.7 [RFC4657]. • Three code points requested in the PCE OF Registry (defined in draft-leroux-pce-of). • Global Constraints (GC) field • Max Link Util, Min Link Util, Max Hop, Exclusion of links/nodes • Global Concurrent Vector (GCV) – use of SVEC object [PCEP] • GCO related Error Indicators • Multi-Session • Indicator, session sequence number, final session indicator 68th IETF – Prague, Czech Republic March 2007
Requirements Updates (New) • Overbooking Factor added in the Global Constraint Field (Ning So, Verizon) • Disruption Minimization Mechanism in Bulk Re-optimization/Migration • The Request for the Order in which LSPs should be re-optimized (i.e., migration path) • In response to “ordering” request from the PCC, the PCE MUST indicate the order in which LSPs should be re-optimized: setup order and removal order • Inclusion of the set of previously computed paths to avoid double bandwidth accounting • Make-before-Break indicator 68th IETF – Prague, Czech Republic March 2007
PCEP Protocol Extensions • GCO Indicator – a new flag (C flag) in the SVEC object • GOF (Global Objective Function) - three code points requested in the PCE OF Registry • Request for the order of LSP to minimize disruption in case of bulk provisioning – a new flag (D flag) in the RP object • Make-before-break Indicator – a new flag (M bit) in the RP object • The Order Response TLV defined in the RP object in the PCRep Message: Setup Order and Delete Order • Global Constraints (GC) Object defined: MU, mU, OB, MH, XRO • Multi-Session (MS) Object is defined: F bit, M-Session ID, Sequence Number • Two new flags added to NO-PATH-VECTOR TLV in the NO-PATH object: 0x03: no migration path found; 0x04: no feasible solution found • New Error-Type (14) and two new Error-values are defined to indicate errors associated with GCO: memory overflow, GCO not capable • A new Error-Value (3) is defined in the existing Error-Type (5) to indicate “GCO not allowed under policy.” 68th IETF – Prague, Czech Republic March 2007
Summary & Next Steps • GCO application is within Working Group charter. • WG charter: Functional specification of MPLS and GMPLS Traffic Engineered LSP path computation models involving Path Computation Element(s). This includes the case of computing the paths of intra and inter-domain TE LSPs. Such path computation includes the generation of primary, protection and recovery paths, as well as computations for (local/global) reoptimization and load balancing. • RFC 4657 Section 5.1.17 – “Synchronized Objective Functions” (Global objective); Section 5.1.7 – “correlated multiple requests” • We have made significant progresses since 67th IETF • Complete Set of Requirements • Protocol Extensions in Good Progress • Request to be accepted as WG draft when WG is ready 68th IETF – Prague, Czech Republic March 2007