Darwin

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Darwin

• Hwang, Sun Ha
• Real-Time Systems Laboratory,
• School of Information and Communication
  Engineering,
• Sungkyunkwan University,
• E-mail shhwang_at_rtlab.skku.ac.kr

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Contents

• Intro
• Resource management mechanism
• System Architecture
• Usage
• Conclusion
• Summary

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Intro

• Darwin Project
• A middleware environment for next generation IP
  networks
• Goal
• Offering Internet users a platform for
  value-added and customizable services
• Customizable resource management that support QoS

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Based on..

• Service-oriented networks characteristics
• Manage a broader set of resources that includes
  computation, storage, and services from other
  providers
• Interdependencies between different types of
  resources
• Service-specific notions of QoS

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Based on..

• Three dimension of customization is needed
• Space
• What network resources are needed
• Time
• How the resources are applied over time
• Services
• How the resources are shared among different
  Service providers and applications
• Virtual mesh
• Core abstraction
• Providers can manage and control the resources in
  their virtual mesh in a way that best fits
  their needs
• Customized management

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Resource management mechanism

• High-level resource selection Xena
• Performing tradeoffs between services according
  to the application-selected value metric
• Coordinated allocations for inter-dependent
  resources
• Interconnect incompatible services or endpoints
• Runtime resource management Delegates
• Injects application or service-specific dynamic
  behavior into the network
• Hierarchical scheduling Hierarchical Fair
  Service Curve(H-FSC)
• Provides isolation and controlled sharing of
  individual resources among service providers
• Low-level resource allocation Beagle
• Allocate real network resources(bandwidth,
  buffers, cycle, memory)

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System Architecture
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System Architecture (contd)

• Application running on end-point
• Requests for service to a resource broker(Xena)
• Identify the resources needed to satisfy the
  request
• passes this information to a signaling
  protocol(Beagle)
• Beagle interacts with a local resource manager to
  acquire and set up the resource
• Resource brokers
• have to know what resource pools they are allowed
  to use
• Signaling protocol local manager
• Must be able to validate the resource allocation
  request and set up appropriate billing or
  charging

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System Architecture (contd)

• A distinguishing feature of the Darwin
  architectural approach
• Mechanisms can be customized according to user
  specific service needs defined by space,
  organization and time constraints

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System Architecture (contd)

• Emphasize
• The need for customization of resource management
• Hierarchical resource management(link sharing)
• Support for resource including not only
  communication, but also computation and storage
• Implementation
• PC-based routers running the NetBSD and FreeBSD
  OS
• Code for Darwin scheduler, beagle has been
  released(http//www.cs.cmu.edu/darwin)

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Conclusion

• Customizable resource management based on concept
  of a virtual network.
• global domain-specific optimizations using
  brokers
• delegates support responsive customize runtime
  resource management
• hierarchical scheduling supports isolation and
  controlled resource sharing for flows and flow
  aggregates
• signaling allocates resources and installs
  delegates based on high level resource
  specifications
• customization supports application-specific QoS

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Summary

• Darwin Four inter-related resource management
  mechanisms
• Resource broker called Xena
• Runtime resource management using Delegates
• H-FSC hieratical packet scheduling
• Resource allocation protocol called Beagle
• The key property of all these mechanisms
• They can be customized according to service
  specific needs

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References

• Prashant Chandra, Yang-hua Chu, Allan Fisher, Jun
  Gao, Corey Kosak, T.S. Eugene Ng, Peter
  Steenkiste, Eduardo Takahashi, Hui Zhang, Darwin
  Customizable Resource Management for
  Value-Added network Services, Carnegie Mellon
  University, Nov 15,2000
• Andrew T. Campbell, Herman G. De Meer, Michael E.
  Kounavis, Kazuho Miki, John B. Vicente, and
  Daniel Villela, A Survey of Programmable
  Networks, Center for Telecommunication Research,
  Columbia University, University of Hamburg,
  Hitachi Limited, Intel corporation

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Intro(contd)

• The integrated set of customizable resource
  management tools ? Darwin project
• Resources allocated to applications or providers
  will be shared dynamically

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Detail

• The process of allocating resources
• Resource discovery ? xena
• Locating available resources that can potentially
  be used to meet application requirements
• Solving an optimization problem ? xena
• Identifying the resources that are needed to meet
  the application requirements, while maximizing
  quality and/or minimizing cost
• Resource have to be allocated by contacting the
  providers that own them ? Beagle

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Detail

• Delegate
• Flow definition
• Resources management
• Flow redirection
• Monitor network status
• Communication
• Scheduling algorithm
• An important feature of H-FSC is that entities
  sharing the resource at different levels in the
  resource hierarchy can manage their share of
  the resources independently

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Usage

• Applications that have been modified to
  explicitly use some or all of the Darwin
  mechanisms
• Each mechanisms can also be used in isolation