Address Resolution for GMPLS controlled PSC Ethernet Interfaces draft-ali-arp-over-gmpls-controlled-ethernet-psc-i-03.txt

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Address Resolution for GMPLS controlled PSC
Ethernet Interfaces draft-ali-arp-over-gmpls-con
trolled-ethernet-psc-i-03.txt
Zafar Ali (zali_at_cisco.com) Hassan Sheikh
(hassans_at_cisco.com) Tomohiro Otani
(otani_at_kddilabs.jp)
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Agenda

• How comments from CCAMP meeting at last IETF are
  addressed?
• Summary of recommendations proposed.
• Next Steps.

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Changes from the last revision

• Summary of the minutes of CCAMP meeting at IETF
  67 (http//www3.ietf.org/proceedings/06nov/minutes
  /ccamp.html)
• Agree on defining a common addressing scheme for
  ARP Resolution.
• No extension to RSVP-TE for this purpose.
• The new version has been updated accordingly.

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Scope of the Draft

• Issues with the use of ARP over GMPLS controlled
  Ethernet router-to-router (PSC) interfaces
  transiting from a non-Ethernet core, e.g., FSC or
  LSC GMPLS core.
• When an LSP Path is established between the
  Ingress Router to Egress Router, Ethernet
  interface at the two routers comes up. However,
  before this LSP (or interface) can forward any IP
  traffic, MAC address of the remote router needs
  to be learned.
• Point-to-point Ethernet Interfaces.

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Inter-op Issues in resolving ARP

• Inter-op issues in resolving ARP among vendors
  found at various public events/ private testing
  efforts.
• Some routers send ARP request for the address
  of the TE link at the end-point.
• Some LSRs send ARP request using the tunnel IF
  address at the end-points.
• Some vendors do not reply to ARP request sent
  to the loopback address. Also, should the
  loopback interface address from optical or packet
  instance be use.
• Solution At last IETF meeting we agreed to
  define a common addressing scheme for ARP
  Resolution.

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Addressing Scheme for ARP Resolution

• An LSR SHOULD use tunnel interface address for
  ARP request.
• This would also address the issue associated
  with the use of disjoint subnets used with
  numbered TE links between the Ingress LSR and the
  Optical node, and the Egress LSR and the optical
  node.
• An LSR, based on a local decision, can determine
  if the Interface is point-to-point and SHOULD
  resolve APR using loopback addresses.

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ARP Round-trip Delay

• ARP round-trip delay before traffic can be
  forwarded to the protecting LSP, when doing a
  cutover to a "cold standby" LSP (e.g., 11 Case).
• In 11 or 1N protection without extra traffic,
  the protecting LSP cannot carry any traffic until
  the traffic is switchover.
• End-point MAC address needs to be re-learned once
  the ARP cache entries time-out, or every time the
  path taken by the GMPLS LSP changes (e.g., due to
  re-routing or re-optimization).
• The Round Trip latency implies traffic loss
  (i.e., no O(50 msec) guarantees).

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Addressing ARP Round-trip Delay Issue for
Protected tunnels

• Enable ARP learning for protecting LSP ahead of
  time.
• The ARP cache SHOULD NOT timeout the ARP entry on
  both the working and the protecting LSPs.

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Next Steps

• We would like to see WG feedback on this
  Document.
• We would like to request WG to accept this ID as
  a WG document.

Thank You