Choices in Reservation operation

1. Choices in Reservation operation 1PC/2PC, start_time/ASAP, explicit/automatic Tomohiro Kudoh, AIST

2. Reservation options • 1PC/2PC • 2PC has “held” state, and must be committed before provisioning • Reservation confirmation • Whether the root requester confirm success of all reservations • 2PC inherently confirms success of reservations • Start time parameter • Specify exact start time / ASAP request • If the start time is ASAP, it is called immediate reservation • Trigger of provisioning • Explicit: signaling message from the root requester • Automatic: Each leaf provider NSA provision at the specified start time based on its own timer 2

3. 1PC without reserve confirmation Resource available Resource not available Resource provisioned Provider a Requester Provider b Provider a Requester Provider b reserve reserve reserve reserve GB GB provision provision GB GB provision provision Good case Bad case 3 Very nondeterministic behavior

4. Need for fail/rollback Resource available Resource not available Resource provisioned Requester Provider b Provider a Requester Provider b reserve reserve GB GB provision provision fail rollback Protocol will need to support fail/rollback for cases where failure happens after reserve/commit 4

5. Summary for reserve confirmation 1PC without reserve confirmation is not appropriate for NSI, because of its non-deterministic behavior. I propose not to use this option for NSI. 5

6. Possible reservation operations 6

7. 1SE and 2SE: comparison Provider a Requester Provider b Provider a Requester Provider b GB GB ack ack GB GB nack 1SE ack cancel provision provision Provider a Requester Provider b Provider a Requester Provider b reserve reserve reserve reserve reserve reserve reserve reserve GB GB held held GB GB abort 2SE held “commit” can be piggy backed to “provision” abort commit commit provision provision “all” case “none” case 7

8. Adding failure after commit Provider a Requester Provider b Provider a Requester Provider b GB GB ack ack GB GB nack 1SE ack cancel provision provision Provider a Requester Provider b Provider a Requester Provider b reserve reserve reserve reserve reserve reserve reserve reserve GB GB held held GB GB abort 2SE held “commit” can be piggy backed to “provision” abort commit commit provision provision rollback fail “all” case “none” case 8

9. For exact start time/explicit 2PC does not introduce much complexity, compared to 1PC. 2PC is equivalent to 1PC (with confirm) if “commit” is piggy-backed to “provision”. 9

10. 1SA and 2SA: comparison Provider a Requester Provider b Provider a Requester Provider b GB GB ack ack GB GB nack 1SA ack cancel Start time Provider a Requester Provider b Provider a Requester Provider b reserve reserve reserve reserve reserve reserve reserve reserve GB GB held held GB GB abort 2SA held abort commit commit “all” case “none” case 10

11. 1SA and 2SA: comparison (2) Provider a Requester Provider b Provider b provisions resource when at start time, so partial provisioning occurs GB ack GB Start time nack 1SA cancel Provider a Requester Provider b reserve reserve reserve reserve Provider b does not provision resource since no commit message has been received GB held Start time GB abort 2SA abort 11

12. For exact start time/automatic 1PC will introduce non-deterministic behavior for automatic provisioning. 2PC is deterministic. 12

13. 1AE and 2AE: comparison Provider a Requester Provider b Provider a Requester Provider b GB GB ack ack GB GB nack 1AE ack cancel provision provision Provider a Requester Provider b Provider a Requester Provider b reserve reserve reserve reserve reserve reserve reserve reserve GB GB held held GB GB abort “commit” can be piggy backed to “provision” 2AE held abort commit commit provision provision “all” case “none” case 13

14. For ASAP/explicit 2PC does not introduce much complexity, compared to 1PC. 2PC is equivalent to 1PC (with confirm) if “commit” is piggy-backed to “provision”. 14

15. Summary I propose NSI to use 2PC, allowing piggy backed-commit. 15

16. Parameters of immediate reservation • There was a discussion on whether to use (start time, end time) or (stat time, duration) for requesting parameters, and we decided to use (start time, end time) for NSI protocol • They are the same for “exact start time operation”, duration = end time – start time • But they are different for immediate reservation: (ASAP, end time), (ASAP, duration) • If the end time is specified, duration of provisioning is not know, and vice versa. 16

17. Timing issues we should aware • The following timing issues exist, and must be considered, regardless of whether we will use 1PC or 2PC • Time (duration) required to process request, schedule and make resources ready for provision • Time (duration) between a trigger to provision (signaling message or timer) and the time when connectivity for user become available • Time (duration) between a trigger to cancel a provision (signaling message or timer) and the time connectivity disappears • Time (duration) required to deliver a message 17

18. Provisioning timings(1) • Provisioning sequence start time • The time a provider NSA starts action to provision a connection (by timer or signaling) • No preceding processing before this time is required. • Provisioning sequence end time • After this time, provision sequence of another reservation can be started • Connectivity start/end time • The time the user can start/should finish to use the connection • Connectivity end time 18

19. Provisioning timings(2) 19