Modeling Cloud Federations

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Modeling Cloud Federations

Wojciech Burakowski

Warsaw University of Technology, Poland

ICT COST Action IC1304

Autonomous Control for a Reliable

Internet of Services (ACROSS)

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• University of Szeged and MTA SZTAKI, Hungary

• University of Antwerp-iMINDS, Belgium

• University of Zurich, Switzerland

• Deutsche Telekom AG, Germany

• Warsaw University of Technology, Poland

Partners:

Activity TF4: Cloud Federations inside

ACROSS

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• Introduction to Cloud Federation

• Multi-level traffic model for Cloud Federation

–

Level 5: Strategy for handling demand

• some numerical results

–

Level 4: Cloud Federation setting

–

Level 3: Handling Installation Service requests and Service Provision

–

Level 2: Handling Execution Service requests

–

Level 1: Sharing Resources

• Planed evaluation methods

–

Simulation

–

Experimental capabilities

• In European testbeds

• In PL-Lab (Polish) testbed

• Conclusions and future plans

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Introduction to Cloud Federation (1)

New elements comparing to the separated Cloud :

• CF network

• Resources in many Clouds

Potentiality of Cloud Federations vs. Separated Clouds:

• Better resource utilization

• More offered services

Problem:

• More complicated traffic

management Exemplary Cloud Federation with 5 Clouds

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Introduction (2)

Reference Federated Cloud Management Architecture

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Multi-level traffic model for Cloud Federation

OFF-LINE OFF-LINE OFF-LINE ON-LINE Level 4

Cloud Federation Setting

· Resources in Cloud Federation

· types of resources

· number of resources

· Network connecting Clouds

· network topology

· network provision

Level 3 Service of IS requests

· Service specification

- specification of task sequence

· Service provision

-alocating resources to execute particular task

Installing Service (IS) Requests

Level 2 Service of ES requests

· Service of appropriate task sequence

· Allocating tasks to the resources (if more than one resource can serve the task)

Execution Service (ES) Requests

Level 5

Strategies for handing demands

· Distribution of demands between Clouds

Level 1

Task service in cloud resources

· Task scheduling

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Level 5: Strategies for handling requests

in Cloud Federation

Centralized approach

With Home Clouds

• All demans are submitted to Cloud

Federation

• Cloud Federation is managed as one

Cloud

• All resources belong to Cloud

Federation

• Home Clouds have its own users

• The requests are submitted to

Home Clouds

• If no resources in Home Cloud then

they are submitted to Cloud

Federation

Cloud #5

Cloud #4

Cloud #4 Cloud #3Cloud #3

Cloud #2 Cloud #1 Centralized request handling Request submitted by customers Cloud Federation Home Cloud #5 Home Cloud #5 Home Cloud #4 Home Cloud #4 Home Cloud #3 Home Cloud #3 Home Cloud #2 Home Cloud #1 Cloud Federation Centralized request handling Request submitted by particular Clouds if no resources Request submitted by

particular Home Clouds

a)

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Level 5: Strategies for handling requests

Considered systems:

• Separated cloud : SC

• Cloud Federation with Home Clouds : CF-HC

• Cloud Federation with centralized management: CF-C

System description (simple assumptions just for comparison):

• N – number of Clouds in CF

• Ci – number of resources in the i-th Cloud (ass. – all resources are the same)

• αi - arrival rate of requests for each cloud acc. to Poisson distibution (ass. each request demands one resource, resource is not shared)

• hi – service rate of requests in each resource (ass. negative exponential distribution)

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Level 5: Startegies for handling requests

Considered system ( cloud sizes and request arrival rate to each Cloud are the same): N=5,10; Ci=10,20; αi=5(10)-9.5(19); hi=1

Conclusions:

• If capacity of the CF is growing (greater number of resources) then loss rate is going less

• CF has more resources than SC so lost rate

• From the point of loss rate the FC-HC has the same characteristics as CF-C

• Final conclusion – CF has better performances than SC

1,00E-10 1,00E-09 1,00E-08 1,00E-07 1,00E-06 1,00E-05 1,00E-04 1,00E-03 1,00E-02 1,00E-01 1,00E+00 4 5 6 7 8 9 10 Loss ra te

Offered Load per cloud

Loss rate - 10 resources in each cloud

SC CF-HC and CF-C: 5 Clouds CF-HC and CF-C: 10 Clouds 1,00E-10 1,00E-09 1,00E-08 1,00E-07 1,00E-06 1,00E-05 1,00E-04 1,00E-03 1,00E-02 1,00E-01 1,00E+00 9 10 11 12 13 14 15 16 17 18 19 20 Los s r at e

Offered Load per cloud

Loss rate - 20 resources in each cloud

SC

CF-HC and CF-C: 5 Clouds CF-HC and CF-C: 10 Clouds

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Level 5: Strategies for handling Demands

Considered system ( Cloud sizes are identical but arrival rates to each Cloud are different): N=5 ; Ci=10;hi=1;α1=2, ; α2=4, ; α3=6, ; α4=8, ; α5=10

Conclusions:

• All Couds in FC-HC have better resource utilization comparing to SC

• FC-C vs. FC-HC :

• Loss rate for each Home Cloud is the same

• Home Cloud with greater request rate in the FC-HC scheme utilizes more resources

comparing to FC-C scheme

• Home Cloud with less request rate utilizes less resources comparing to FC-C scheme

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Level 4: Cloud Federation setting

CF using independent SLAs

Cloud C Cloud A Cloud B Cloud D Virtual Network Infrastructure SDN enabled device Cloud D User Cloud E Cloud federation management Network Operator SLA NaaS

CF using Virtual Network Infrastructure

Network level: new element in CF comparing to SC

Network design aspects:

• Profile and volume of traffic submitted to the network

• Requirements for QoS quarantees, Which Classes of Services are needed, if needed

• Methods for network dimension and adaptation to current needs (when traffic is changed in time)

• Which technology: SDN ?

Exemplary two approaches

Remark: if some clouds will have worst connections when their resources can be not choosen

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Level 3: Handling Service Installation

requests

Requests for installing and provision of a new service, named IS requests that

are send by service providers to Cloud Federation owners

• Service specification

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Level 3: Handling Service Installation

requests

Service specification (acc. to SoA- Software Oriented Architecture):

• The specification of a service has a form of specification (in the simplest case) of task

sequence, that should be executed in a priori defined order

• More complicated task sequence – with tasks executed in paralell

• Task description: service number, sequence number, …

Different task requences corresponding to

different services Example of task requence with tasks

executed in parallel

Task (1,1) Task (1,2) Task (1,3) Task (1,4)

Task (2,1) Task (2,2)

Task (3,1) Task (3,2) Task (3,3)

ES requests for service#1

ES requests for

service#3 Task (1,1) Task (1,3) Task (1,4)

Task (1,2,1)

Task (1,2,2)

Task (1,2,3)

Tasks (1,2,1), (1,2,2) and (1,2,3) are executed in parallel in different

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Level 3: Handling Service Installation

requests

Service provision

• responsible for chosing a number of resources to execute paricular tasks

• Execution of specific task could be possible done by more that one resource (not necessary belonging to the same cloud)

• Service provision process should be updated depending on service requests rate

of given service

Task1 Task2 Task3 Cloud A

Cloud B

Remark: For service provitio we dedicate a subset of all resources

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Level 2: Handling service execution

requests

Requests for service execution are send by users to Cloud Federation (CF-C) or

Home Clouds (CF-HC)

• Service execution demands execution of task sequence

• The issue is (possible dynamic) task allocation taking into account load

conditions in resources

Cloud B

Which resource we allocate ?

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Comparing requests for service setting

and service execution

IS requests ES requests

Requirements for time execution

off line on line

Arrival rate hours, days seconds, minutes

Issues to be solved How to allocate resources, how to provision

how to do re-provision

How to allocate execution of tasks?

Remark: Provision and execusion processes are dependent: the quality of service

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Level 4: Cloud Federation setting

Cloud Federation resources (compte resources)

• Detail knowledge about resources in all Clouds

• We should take into account that compute resources

• are packed in racks and organized in clusters (high

bandwidth access)

• are often connected to shared storage infrastructure (

databases)

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Dependences between levels

Level 4

Cloud Federation Setting

Level 3 Service of IS requests

Level 2 Service of ES requests

Level 5

Strategies for handing demands

Level 1

Task service in cloud resources Final assesment of offered

quality

Try to improve

Try to improve Try to improve

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Planed evaluation strategy

• To define use cases

• The best solution - to take use cases currently studied by

European projects

• To use CloudSim or to develop simulation tool

• It looks that CloudSim is not suited

• Try to do some experiments

• in one of European testbeds

• Under study

• in PL-LAB

• that will be connected to European testbed infrastructure by

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PL-Lab

PL-LAB

• finished at the and of this year

• we are thinking about designing

testbed for CF

• SDN net (about 30 switches)

• Many servers • generator./analyser Gdańsk Warszawa Poznań Wrocław Gliwice Warsaw University of Technology 6 SDN switches 15 Servers Poznań Supercomputing and Networking Center

16 SDN switches

19 servers

GÉANT, FED4FIRE, XIFI, FIWARE

Wrocław University of Technology 2 SDN switches 25 servers Gdańsk University of Technology

6 servers National Institute of _{Telecommunications}

18 SDN switches 24 servers Silesian University of Technology 6 SDN switches 4 servers