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Recovery Requirements, Fault Notification Protocol, and LMP CCAMP WG (IETF-56) March 19, 2003. Peter Czezowski peterc@fla.fujitsu.com. Outline. 3 drafts on failure recovery and fault notification draft-czezowski-optical-recovery-reqs-01.txt draft-rabbat-fault-notification-protocol-02.txt
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Recovery Requirements, Fault Notification Protocol, and LMPCCAMP WG (IETF-56)March 19, 2003 Peter Czezowski peterc@fla.fujitsu.com
Outline • 3 drafts on failure recovery and fault notification • draft-czezowski-optical-recovery-reqs-01.txt • draft-rabbat-fault-notification-protocol-02.txt • draft-soumiya-lmp-fault-notification-ext-00.txt • Summary and recommendations Peter Czezowski <peterc@fla.fujitsu.com>
Optical Network Failure Recovery Requirements • draft-czezowski-optical-recovery-reqs-01.txt Peter Czezowski (Fujitsu Labs of America) Toshio Soumiya (Fujitsu Laboratories) Kohei Shiomoto (NTT Network Innovation Labs) Shoichiro Seno (Mitsubishi Electric Corp.) • describes requirements for control plane-based schemes for recovery from data plane failures • starting point for work on protection and restoration schemes, protocols and mechanisms Peter Czezowski <peterc@fla.fujitsu.com>
Optical Network Failure Recovery Requirements (2) • organization of the draft • introduction • terminology • failure recovery requirements • overview of requirements • shared mesh-based recovery • failure notification mechanisms • list of 17 requirements • conclusions Peter Czezowski <peterc@fla.fujitsu.com>
Optical Network Failure Recovery Requirements (3) • four categories of requirements • meet (potentially strict) time constraints • be efficient with resources • scalability of recovery scheme • flexibility of recovery scheme • changes since –00.txt • some rewording for clarification • added a figure and example scenario regarding fault notification Peter Czezowski <peterc@fla.fujitsu.com>
Fault Notification Protocol for GMPLS-Based Recovery • draft-rabbat-fault-notification-protocol-02.txt Richard Rabbat (Fujitsu Labs of America) Vishal Sharma (Metanoia) Norihiko Shinomiya (Fujitsu Laboratories) Ching-Fong Su (Fujitsu Labs of America) Peter Czezowski (Fujitsu Labs of America) • after considering the requirements, it is evident that fault notification is critical for scalability and flexibility of recovery scheme Peter Czezowski <peterc@fla.fujitsu.com>
Fault Notification Protocol for GMPLS-Based Recovery (2) • we prefer a “per failure” limited flooding-based approach to fault notification • scalability: per failed link vs. per failed LSP (even when you consider bundling LSP notifications) • flexibility: nodes “off the working path” may take immediate recovery actions • policy based • proactive Peter Czezowski <peterc@fla.fujitsu.com>
Fault Notification Protocol for GMPLS-Based Recovery (3) • organization of the draft • overview • requirements at path set-up • protocol steps • fault notification analysis • discussion of notification message delays • description of notification message data • conclusions • appendix: delay calculations Peter Czezowski <peterc@fla.fujitsu.com>
Fault Notification Protocol for GMPLS-Based Recovery (4) • changes since –01.txt • some rewording for clarification • addressed issues about nodes that require sequential actions for reconfiguration vs. nodes that allow one-shot reconfiguration • added description of generic fault notification data • removed Appendix B: Algorithm for finding sub-graph Peter Czezowski <peterc@fla.fujitsu.com>
Extensions to LMP for Flooding-based Fault Notification • draft-soumiya-lmp-fault-notification-ext-00.txt Toshio Soumiya (Fujitsu Laboratories) Peter Czezowski (Fujitsu Labs of America) Takeo Hamada (Fujitsu Labs of America) Shinya Kanoh (Fujitsu Laboratories) • LMP is a good candidate for extension to implement flooding-based fault notification • already includes fault management features • can reuse many protocol objects Peter Czezowski <peterc@fla.fujitsu.com>
Extensions to LMP for Flooding-based Fault Notification (2) • organization of the draft • overview • fault recovery scenario • additional LMP message formats • additional LMP object definitions • priority-based recovery • conclusions Peter Czezowski <peterc@fla.fujitsu.com>
Extensions to LMP for Flooding-based Fault Notification (3) • two additional message formats <FaultNotify Message> ::= <Common Header> <MESSAGE_ID> [<TTL>] <FAULT_ID> <LOCAL_NODE_ID> {<LINK_ID>[<CHANNEL_STATUS>]...} or <FaultNotify Message> ::= <Common Header> <MESSAGE_ID> [<TTL>] <FAULT_ID> [<SRLG ID> ...] <FaultNotifyAck Message> ::= <Common Header> <MESSAGE_ID_ACK> Peter Czezowski <peterc@fla.fujitsu.com>
Extensions to LMP for Flooding-based Fault Notification (4) • additional TTL object definition TTL Class (Class = TBD) C-Type = 1, Time to Live (= Hop Count) 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TTL | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ TTL: 8 bits This is an unsigned integer to indicate a remaining hop count value. A node receiving a FaultNotify message having a TTL of zero MUST silently discard the message. Peter Czezowski <peterc@fla.fujitsu.com>
Extensions to LMP for Flooding-based Fault Notification (5) • additional FAULT_ID object definition FAULT_ID Class (Class = TBD) C-Type = 1, Failure Identifier 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | FaultId | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ FaultId: 16 bits This MUST be a node-wide unique unsigned integer. The FaultId identifies the sequence of failures. A node increases the value when it detects a failure. Peter Czezowski <peterc@fla.fujitsu.com>
Summary • draft-czezowski-optical-recovery-reqs-01.txt • we believe the draft fits within CCAMP charter and complements the work done by P&R Design Team • request for consideration as WG draft • draft-rabbat-fault-notification-protocol-02.txt • we believe the draft fits within CCAMP charter and complements the work done by P&R Design Team • request for consideration as WG draft • draft-soumiya-lmp-fault-notification-ext-00.txt • we have running code for these extensions • does CCAMP have interest in this draft? Peter Czezowski <peterc@fla.fujitsu.com>