Cross Support Transfer Services – Cross Support Transfer Services – Service Control ServiceService Control Service

23-27 March 2015

Pasadena, California, USA

John PietrasGlobal Science and Technology, Inc, Greenbelt, MD, USA

www.ccsds.org

Purpose of the Service

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Allow a Mission to

Invoke pre-defined/pre-approved actions on the configuration of space communication services being provided during the execution of a Service Package

Invoke changes to configuration parameters that have been pre-approved for dynamic resetting

Do we need to allow service management-level directives?• E.g., a directive to override an Events Sequence

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Overview of Capabilities of SC-CSTS

User can invoke directives on any Functional Resource instance that is configured as part of the Service Package that contains the SC-CSTS service

Directives must be pre-defined for each FR type Each Complex (Provider CSSS) is free to support the directives and reconfiguration

parameters that are appropriate

Two kinds of directives Control directives (e.g., ‘forward link sweep’, executed by a forward link carrier

transmission FR)• Directive-qualifier contains the name of the functional resource instance that is to execute

the directive, and possibly one or more parameter values needed by the directive Reconfiguration directive

• Directive-qualifier contains one or more pairs ofo Parameter nameo New parameter value

Controllable parameters are a subset of the managed parameters that will be registered with SANA

No need to define new OIDs for controlled parameters Approach could be extended to Space Link Events Sequences For further analysis – should controllability be an attribute of each managed parameter, or should

all managed parameters be controllable by default and only constrained per Service Agreement?

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CSTS EXECUTE-DIRECTIVE Operation

Parameters Invocation Acknowledgement Return

invoker-credentials M

performer-credentials M M

invoke-id M M M

procedure-instance-identifier M

result M M

diagnostic C C

directive-identifier M

directive-qualifier M

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Acknowledged operation

directive-identifier: identifies the action that is to be performed (OID)

directive-qualifier: provides complementary data to directive-identifier CHOICE of

• setOfParamNameAndValue (ParameterNameValueSet)• directiveQualifierExtension (Embedded)

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ParameterNameValueSet Type

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ParameterNameValueSet ::= SET OF SEQUENCE{ parameterName Name, parameterValue TypeAndValueComplexQualified} TypeAndValueComplexQualified ::= CHOICE{ typeAndValue [0] TypeAndValue, complexSequence [1] SEQUENCE OF TypeAndValue, complexSet [2] SET OF TypeAndValue}

TypeAndValue ::= CHOICE{ integer [0] SEQUENCE OF INTEGER, integerPositive [1] SEQUENCE OF IntPos, intUnsigned [2] SEQUENCE OF IntUnsigned, duration [3] SEQUENCE OF Duration, characterString [4] SEQUENCE OF VisibleString, boolean [5] SEQUENCE OF BOOLEAN, octetString [6] SEQUENCE OF OCTET STRING, float [7] SEQUENCE OF REAL, time [8] SEQUENCE OF Time, enumerated [9] SEQUENCE OF IntUnsigned, objectIdentifier [10] SEQUENCE OF OBJECT IDENTIFIER, typeAndValueExtension [100] Extended}

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svcSetParameter

Established as a generic service OID

Allows the EXECUTE-DIRECTIVE operation to Set the parameter value of a dynamically-modifiable

procedure configuration parameter of the CSTS• Such parameters must be specified by the procedures or

service specifications that use the Execute-Directive Set the value of a dynamically-modifiable Functional

Resource configuration parameter• SFW should restrict the default behavior to FR instances that

are directly associated with the CSTS that executes a procedure that contains the EXECUTE-DIECTIVE operation

o See the GET operationo SC-CSTS will override that default behavior

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Note - the word “Event” should be deleted from 3.12.2.2.2.5 of the SFW

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Application of the EXECUTE-DIRECTIVE Operation to the SC-CSTS

SFW directive-qualifier capabilities appears to be fine for re-setting configuration parameter values

Other actions SFW directive-qualifier capabilities do not allow “whole” FR instances to be

the target of a directive Invoking actions on FR instances will require use of the

directiveQualifierExtension parameter to add an extension syntax that allows invoking the action directly on an FR instance without specifying a parameter

• Extended directive qualifier may optionally have a TypeAndValueComplexQualified component

FR-specific directive OIDs are registered under the crossSupportFunctionalities: functionalResourceX: directivesId subtree

Is the ability to invoke actions directly on a FR instance generally useful?

If so, the SFW directive-qualifier could be extended Then no extension would be required for SC-CSTS

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Other Considerations

Relationship of SC-CSTS instance to Service Package Assume a single instance per Service Package

• Reasonable limitation and safest approach Presence of SC-CSTS implied in Service Request, based on provision

of Service Agreement Service Package Result will supply binding information NOTE – Need to also address possibly multiple instances of MD-CSTS

• Does Service Package Request need to explicitly specify the number of MD-CSTS instances?

Accountability tie-in Association of SC-CSTS with the Service Package should be sufficient

to uniquely trace directives

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