Proposed Scaling Related Class/Datatypes

Attribute Name

Applied Stereotypes

Multiplicity

Type

Description

id

M

1

Identifier

Unique identifier of this aspect in the VNFD.

name

M

1

String

Human readable name of the aspect.

description

M

1

String

Human readable description of the aspect.

maxScaleLevel

M

1

PositiveInteger

The maximum scaleLevel for total number of scaling steps that can be applied w.r.t. this aspect. The value of this attribute corresponds to the number of scaling steps can be applied to this   aspect when scaling it from the minimum scale level (i.e. 0) to the maximum scale level defined by this attribute. See note 2.

aspectDeltaDetails

M

0..1

AspectDeltaDetails

A specification of the deltas in terms of number of instances of VNFCs and virtual link bit rates that correspond to the scaling

steps of this aspect. A cardinality of zero indicates that this mapping has to be specified in a lifecycle management script or be otherwise known to the VNFM.

The information in this attribute, if provided, shall be consistent with the information provided in the "InstantiationLevel" information element.

If this attribute is provided, it shall be provided for all scaling aspects.

See notes 1 and 3.

NOTE 1:  In the present release of the specification, support for modifying the internal VNF topology during the scaling of the internal VLs, is not required.

NOTE 2:  A scaling step is the smallest increment by which a VNF can be scaled for a particular aspect. Scaling by a single step does not imply that only one VNFC instance is created or removed. It means that one or more VNFC instances are created from the same VDU or from different VDUs, or that a more complex setup occurs.

NOTE 3: The presence of this attribute does not preclude associating lifecycle management scripts to scaling-related events in the VNFD.

NOTE 4: void.

Attribute Name

Applied Stereotypes

Multiplicity

Type

Description

deltas

M

1.N

ScalingDelta

Declares different scaling deltas, each of which is applied for one or more scaling step of this aspect.

stepDeltas

M

0..N

Identifier (Reference to ScalingDelta)

Identifiers of the individual scaling deltas to be applied for the subsequent scaling steps of this aspect.

The first entry in the array shall correspond to the first scaling step (between scale levels 0 to 1) and the last entry in the array shall correspond to the last scaling step (between maxScaleLevel-1 and maxScaleLevel).

Each referenced scaling delta shall be declared in the "deltas" attribute.

See note.

NOTE: A scaling aspect for which only one scaling delta is defined (i.e. for which the "deltas" attribute has only one entry) is called a "uniform aspect". The single delta that is declared for a uniform aspect is called the "uniform delta"; it is applied in all scaling steps of that aspect. For a uniform aspect, the "stepDeltas" attribute may be omitted, as the same scaling delta is applied for all scaling steps.

Attribute Name

Applied Stereotypes

Multiplicity

Type

Description

scalingDeltaId

M

1

Identifier

Identifier of this scaling delta.

vduDelta

M

0..N

VduLevel

The number of VNFC instances based on particular VDUs to be created or removed.

See note

virtualLinkBitRateDelta

M

0..N

VirtualLinkBitRateLevel

The bitrate to be added or removed to virtual links created from particular virtual link descriptors.

See note

NOTE:  At least one of the attributes "vduDelta" and "virtualLinkBitRateDelta" shall be present.