334   Select a SBO object twice

Created: 28 Jun 2006

Status: In Force (green)

Part: Part 7-2 (2003)

Links:

Page: 142

Clause: 17.3.3

Paragraph:

Category: Issue for edition 2 of this part

Issue

Part 10 defines a test case (CtlN2) to select the same SBO control object twice from the same/another client. It's not defined in the standard what the expected result should be or what options are allowed. Some applications return an select response- with AddCause "command-already-in-execution" or "Already-selected". Other applications may accept the second select to reset the select timeout.

Proposal

Clarify the expected result

Discussion Created Status
As the test script was done before the Tissue solution,the Tissue solution is the correct one, at least for edition 2 IEDs, and the test script has to be adapted accordingly. 20 Aug 08 In Force (green)
I think some additional clarification is required for this Tissue as to what the actual solution to implement is for an IED.

Reading the final proposal I understand the solution is to return a response- with an appropriate AddCause.

However, reading the conformance test procedures (V2.1) and associated Kema test scripts, it seems the solution is to return a Response+ and reset the select timer.

Which is the correct solution? That described by this tissue or by what is within the conformance test specification.
20 Aug 08 In Force (green)
17 Feb 07 In Force (green)
Editor meeting : december 2006.
Reseting the SBO Timeout timer may lead to security issues. the purpose of the SBO Timeout was to introduce an autamtic un-selection to avoid that a control object remains un-available for a long time after a selection.
The proper AddCause depends on the state of the state machine associated to the control object.
If the second select occurs before the operate request, then the AddCause shall be Already-selected.
If the second select occurs after the operate request, then the Addcause shall be command-already-in-execution
In both case, regardless if same or another client.
15 Dec 06 Ballot Period
Re-entry: The old "UCA" specification indicated that the second select reset the SBO timeout (e.g. the full period of time became available to the select). This is the behavior that I suggest. 28 Jun 06 Discussion (red)

 

Privacy | Contact | Disclaimer

Tissue DB v. 23.12.13.1