selective redundancy in network-as-a-service: differentiated qos in multi-tenant clouds
TRANSCRIPT
Selective Redundancy in Network-as-a-Service:Differentiated QoS in Multi-Tenant Clouds
Pradeeban Kathiravelu, Luıs Veiga
INESC-ID LisboaInstituto Superior Tecnico, Universidade de Lisboa
Lisbon, Portugal
11 th International Workshop onEnterprise Integration, Interoperability and Networking (EI2N 2016)
26 th October 2016, Rhodes, Greece.
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Introduction
Introduction
I Cloud data centers consist of various tenants with multiple roles.I Differentiated Quality of Service (QoS) in multi-tenant clouds.
I Service Level Agreements (SLA).I Different priorities among tenant processes.
I Network is shared among the tenants.I End-to-end delivery guarantee despite congestion for critical flows.
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Introduction
Software-Defined Networking (SDN) for Clouds
I Cross-layer optimization of clouds with SDN.I Centralized control plane of the network-as-a-service.
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Introduction
Middleboxes in the cloud networks
I Middleboxes - hardware and software.I Device that manipulates network traffic, other than packet forwarding.
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Introduction
Motivation
I How to offer differentiated QoS and SLA in multi-tenant networks?I Application-level user preferences and system policies.I Performance guarantees at the network-level.
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Introduction
Motivation
I How to offer differentiated QoS and SLA in multi-tenant networks?I Application-level user preferences and system policies.I Performance guarantees at the network-level.
I More potential in having them both!I SDN, Middleboxes, . . .
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Introduction
Goals
I How to offer differentiated QoS and SLA in multi-tenant networks?I Leverage SDN to offer a selective partial redundancy in network flows.I FlowTags - Software middlebox to tag the flows with contextual
information.
I Application-level preferences to the network control plane as tags.I Dynamic flow routing modifications based on the tags.
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Solution Architecture
SMART
I An SDN Middlebox Architecture for Reliable Transfers.
I An architectural enhancement for network flows allocation, routing,and control.
I Timely delivery of priority flows by dynamically diverting them to aless congested path.
I Cloning subflows of higher priority flows.
I An adaptive approach in cloning and diverting of the flows.
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Solution Architecture
Contributions
I A cross-layer architecture ensuring differentiated QoS.I A context-aware appraoch in load balancing the network.
I servers supporting multihoming, connected topologies, . . .
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Solution Architecture
SMART Approach
I Divert and clone subflows by setting breakpoints in the flows in theirroute to avert congestion.
I Trade-off of minimal redundancy to ensure the SLA of priority flows.I Adaptive execution with contextual information on the network.
I Leverage FlowTags middleboxI to pass application-level system and user preferences to the network.
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Solution Architecture
SMART Enhancements
I When to break and when to merge?I Clone destination.
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SMART Workflow
I: Tag Generation for Priority Flows
I Tag generation query and response.I between the hosts and the FlowTags
controller.
I A centralized controller forFlowTags.
I Tag the flows at the origin.
I FlowTagger software middlebox.
I A generator of the tags.I Invoked by the host application layer.I Similar to the FlowTags-capable
middleboxes for NATs.
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SMART Workflow
III: When a threshold is met
I Controller is triggered through OpenFlow API.
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SMART Workflow
III: When a threshold is met
I Controller is triggered through OpenFlow API.
I A series of control flows inside the control plane.
I Modify flow entries in the relevant switches.
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SMART Workflow
SMART Control Flows: Rules Manager
I A software middlebox in the control plane.I Consumes the tags from the packet.
I Similar to FlowTags-capable firewalls.
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SMART Workflow
Rules Manager Tags Consumption
I Interprets the tagsI as input to the SMART Enhancer
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SMART Workflow
SMART Enhancer
I Core of the SMART architecture.I Gets the input to the enhancement algorithms.I Decides the flow modifications.
I Breakpoint node.I Brekpoint packet.I Clone/divert decisions.
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Implementation
Prototype Implementation
I Developed in Oracle Java 1.8.0.
I OpenDaylight Beryllium as the core SDN controller.I Enhancer and the Rules Manager middlebox as controller extensions.
I Developed as OSGi bundles.I Deployed into Apache Karaf runtime of OpenDaylight.
I FlowTags middlebox controller deployed along the SDN controller.I Originally a POX extension.
I Network nodes and flows emulated with Mininet.I Larger scale cloud deployments simulated.
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Evaluation
Evaluation Strategy
I Data center network with 1024 nodes and leaf-spine topology.I Path lengths of more than two-hops.I Up to 100,000 of short flows.
I Flow completion time < 1 s.I A few non-priority elephant flows.
I SLA → maximum permitted flow completion time for priority flowsI Uniformly randomized congestion.
I hitting a few uplinks of nodes concurrently.I overwhelming amount of flows through the same nodes and links.
I Benchmark: SMART enhancements over base routing algorithms.I Performance (SLA awareness), redundancy, and overhead.
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Evaluation
SMART Adaptive Clone/Replicate with Shortest-Path
I Replicate the subsequent flows once a previous flow was cloned.
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Evaluation
SMART Adaptive Clone/Replicate with ECMP
I Repeat the experiment with Equal-cost multi-path routing.
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Conclusion
Related Work
I Multipath TCP (MPTCP) uses the available multiple paths betweenthe nodes concurrently to route the flows across the nodes.
I Performance, bandwidth utilization, and congestion controlI through a distributed load balancing.
I ProgNET leverages WS-Agreement and SDN for SLA-aware cloud.
I pFabric for deadline-constrained data flows with minimal completiontime.
I QJump linux traffic control module for latency-sensitive applications.
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Conclusion
Conclusion
I ConclusionsI SMART leverages redundancy in the flows as a mean to improve the
SLA of the priority flows.I Opens an interesting research question leveraging SDN, middleboxes,
and redundancy.I Cross-layer optimizations through tagging the flows.I For differentiated QoS.
I Future WorkI Implementation of SMART on a real data center network.I Evaluate against the identified related work quantitatively.
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Conclusion
Conclusion
I ConclusionsI SMART leverages redundancy in the flows as a mean to improve the
SLA of the priority flows.I Opens an interesting research question leveraging SDN, middleboxes,
and redundancy.I Cross-layer optimizations through tagging the flows.I For differentiated QoS.
I Future WorkI Implementation of SMART on a real data center network.I Evaluate against the identified related work quantitatively.
Thank you!Questions?
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