RFC 3215 LDP State Machine January 2002 Table Of Contents 1. Terminology ................................................... 4 2. State Machine for Downstream-on-Demand Mode ................... 4 2.1 An LSR's Behavior in the Case of a Next Hop Change ........... 4 2.2. ATM Switch LSR with No VC-merge Capability .................. 5 2.2.1 LSP Control Block .......................................... 5 2.2.2 States ..................................................... 7 2.2.3 Events ..................................................... 8 2.2.4 State Transitions .......................................... 9 2.2.5 State Machine .............................................. 10 2.2.5.1 State -- "IDLE" .......................................... 10 2.2.5.2 State -- "RESPONSE_AWAITED" .............................. 13 2.2.5.3 State -- "ESTABLISHED" ................................... 16 2.2.5.4 State -- "RELEASE_AWAITED" ............................... 21 2.2.6 Handling the Next Hop Change ............................... 23 2.2.6.1 Next Hop Trigger Control Block ........................... 24 2.2.6.2 States ................................................... 24 2.2.6.3 Events ................................................... 24 2.2.6.4 State Transition for next hop change ..................... 25 2.2.6.5 State Machine ............................................ 25 2.2.6.5.1 State -- "IDLE" ........................................ 25 2.2.6.5.2 State -- "NEW_NH_RETRY" ................................ 27 2.2.6.5.3 State -- "NEW_NH_RESPONSE_AWAITED" ..................... 28 2.2.7 LDP Related Message Handling ............................... 29 2.3. ATM Switch LSR with VC-merge ................................ 31 2.3.1 VC-merge ................................................... 31 2.3.2 Control Block .............................................. 31 2.3.3 State Machines for Downstream-on-demand Mode ............. 34 2.3.3.1 State of the Upstream LSP Control Block's State Machine for Downstream-on-demand Mode ............................ 34 2.3.3.2 Events of the Upstream LSP Control Block's State Machine for Downstream-on-demand Mode ............................ 35 2.3.3.3 State Transitions of the Upstream LSP Control Block's State Machine for Downstream-on-demand Mode .................... 36 2.3.3.4 Upstream LSP Control Block's State Machine for Downstream-on-demand Mode ............................ 37 2.3.3.4.1 State -- "IDLE" ........................................ 37 2.3.3.4.2 State -- "RESPONSE_AWAITED" ............................ 39 2.3.3.4.3 State -- "ESTABLISHED" ................................. 42 2.3.3.4.4 State -- "RELEASE_AWAITED" ............................. 45 2.3.3.5 State of the Downstream LSP Control Block's State Machine for Downstream-on-demand Mode ............................ 47 2.3.3.6 Events of the Downstream LSP Control Block's State Machine for Downstream-on-demand Mode ............................ 47 2.3.3.7 State Transitions of the Downstream LSP Control Block's State Machine for Downstream-on-demand mode .............. 48 Boscher, et al. Informational