Spring-based Resource Management for End-to-end Services in Next-generation Networks

JOURNAL OF INFORMATION SCIENCE AND ENGINEERING

YANG-HUI CHANG, TEIN-YAW CHUNG AND YUNG-MU CHEN

Reporter: Chia-Nung Wang

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Outline

Spring system and definition Spring-based resource allocation

algorithm (SBRA) Spring-based resource compensation

algorithm (SRCA) Reactive force suppression (RFS) Simulation Conclusion

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Spring system and definition For a spring system, there are there at

tributes. Regular length (LR) Minimum length (Lmin) Spring factor (x)

As before, a force ff can decides the length of the spring by this formula:

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Spring system and definition 2 Defines the resource profile of entity i

for a specific resource as: Ri(LRi ,Lmini ,Lmaxi ,xi)

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Spring-based resource allocation algorithm (SBRA) SBRA considers only two important resourc

es: Computing power Bandwidth

There are a simple linear relationship between this two resource. The number of instructions required to process a packet.

The average packet size processed by ci

Correlation index

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SBRA 2The requirements of computing and bandwidth.

Reallocates the computing quota according to bandwidth quota.

Reallocates the bandwidth quota according to computing quota.

allocates a single resource type first, and checks whether the corresponding allocation of the other resource is acceptable.

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SBRA 3 The computing delay:

The transmission delay:

The total delay is:

The delay bound is:

The extra delay is:

Total computing resources allocated to the entities.

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Spring-based resource compensation algorithm (SRCA)

A service S in this study is defined by a set of serially connected entities.

When there are a extra delay , the service manager invoke SRCA to transfer to other iNode.

Whose entities are involved in the same service to compensate for .

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SRCA 2

Will suffer an extra delay

To compensate the extra delay

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SRCA 3

During resource re-allocation, iNodes allocate an extra resource to an entity to compensate for .

The extra resource may affect the QoS of some other services and enable many new extra delay transferences by: Chain Reaction Relation (CRR). Starvation cycle.

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SRCA 4 Chain Reaction Relation (CRR)

If P1∩P2∩P3…∩Pn ≠Ø, there exists a potential chain reaction set:

When CRR occur, it will create many control messages because of delay compensation.

When an iNode re-allocates its resources, it may cause all chain reactions in π and generate many Delay Transference Messages (DT_Message).

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SRCA 5 Starvation cycle:

There must be a service path cycle in a network.

If the cycle exists a resource re-allocation and triggers chain reactions that may cause a starvation cycle.

A starvation cycle not only is responsible for a lengthy call set up time but also triggers an infinite number of DT_Message.

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Reactive force suppression (RFS)

The study applies a novel approach called RFS to reduce the number of delay transferences during a call setup.

RFS employs two mechanisms to suppress the delay transferences: Delay budget ε Reactive force F R

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RFS 2 Delay budget :

If then the iNode re-allocates resources to cover θex, but this re-allocation yields no any new DT_Message.

If , iNode also re-allocates resources to cover θex and makes no any new DT_Message. However, entity x is removed from ξ because it has used up its entire quota.

Finally, if ,then the iNode cannot completely cover θex.

Delay bound Average delay

Idle capability > new resource requirement for x to covering – existing resource

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RFS 3 Reactive force F R

Force F R is used mainly to avoid starvation cycles and reduce the number of DT_Messages generated by CRR.

F R exploits two attributes rf and RF. rf denotes the number of extra delay transferen

ces during the setup of a call. RF denotes the maximum value of rf.

The maximum rf equals ξn in the worst case.

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Simulation

0.96 and 0.98 are better

The improve in RF=n-2 is very close to these at RF=n

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Simulation 2

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Simulation 3No ε

With ε

RF=n

RF=n-2

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Simulation 4

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Conclusion In this paper, author provide an SRCA

algorithm. In this algorithm, an extra delay suffered by an

entity can be compensated by other entities belong to the same service.

Uses a novel scheme, RFS, to avoid excessive control messages.

RFS uses two mechanisms, Delay budget ε and Reactive force FR to limit extra delay transferences during the setup of a call.