Value Flows: Inter-domain Routing Over Contract Links

Hasan T Karaoglu,Murat Yuksel

University of Nevada, RenoFutureNet III, Miami

December 2010

Motivation• Current Architectural Problems of the Internet

– Economics is not reflected inherently on routing• Keeping up with “Value” and “Network Economics”

– Commoditized IP, wholesale transit– “Success of bundling, higher value services“, Labovitz et. al.– Transition to a content-oriented Internet, on-demand

infrastructure, applications, services with Cloud

– Strain on Routing Functions and Dynamics• Traffic Engineering, Rich Policy Requirements

– e.g., Stringent bandwidth and reliability requirements with VoD, VoIP, IPTV and mobility

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Motivation• Structural Inflexibilities

– Limited User Choice: • Value Expression

– Rigid SLA Mechanism• Long Contract Terms, • Establishment Process

– Prefix-based Point-to-Anywhere• e.g., ISP as a “node”.

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Recognizing the “Tussle”: Mechanisms for establishing Negotiation Base

Outline• Motivation• Challenge• Our Solution: Contract Switching Architecture• Problem Definition• Link State Contract Routing• Implementation• Evaluation• Conclusion

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Contract Switching• Defining “contracts” as building blocks.

– Single domain, edge-to-edge, service advertisements

• Recognizing the “value” in traffic– Allow user to express its choice beyond access ISP– Value expression over contracts

• Routing as a service– Compose customized paths for value flows by

stitching single-domain contracts.

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Value Flows• Flow Aggregation

– Manage traffic as flows at core, aggregation

– Keep packet at edge for innovation

• Recognizing “value”– Source-routing– Flow definition– Service customization

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Edge-to-Edge Service• An ISP is abstracted as a set of

“contract links”• Contract link: an advertisable

contract– between peering/edge points i and

j of an ISP– with flexibility of advertising

different prices and capabilities for edge-to-edge (g2g) intra-domain paths

Contract Abstraction

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Contract components performance component, e.g., capacity financial component, e.g., price time component, e.g., term

Problem Definition• Between Packet vs. Circuit Switching

– Flow State, Dedicated Resources– How quickly should one switch?

• Contract Term, Time Scale

• Routing Characteristics– Convergence on multi-metrics (with also price?)– Reachability challenge?

• Transition path to Contract Switching?

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Link State Contract Routing• Link State “Like”

– State? • Not actual conditions, but service definition

– Source-routing • Reservation Signaling on Contract Links

– Route Dissemination• Synchronization, Policy Filters

– Route Calculation• Multiple-metric, Diverse Objectives• Widest-Cheapest Path

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Link State Contract Routing

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User X

2

3

5

ISPA

ISPC

ISPB

1 4

Most cost-efficient route

Max QoS route

OwnerISP

Link

QoS Term

OfferedAfter

Price($/term)

A 1-2 10Mb/s 2hrs 1hr $10A 1-3 40Mb/s 5hrs 15mins $80B 2-4 100Mb/

s3hrs 2hrs $110

C 3-5 20Mb/s 1hr 30mins $8C 4-5 60Mb/s 1day 2hrs $250

Link State Contract Routing

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Link State Contract Routing

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Network Elements• Contract Routers• Network Coordinators

Messaging• Contract Links

• Transit, Sink• Reservation Messages

Implementation• “Overlay” Approach

– BGP and OSPF implementation of SSFNet– Packet level simulation– RSVP “like” signaling protocol

• Strategy: Economic Model, Routing Objectives– Access provider and transit ISP– Non-linear, congestion aware pricing– Congestion aware service provisioning

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Evaluation• Topology

– Tradeoff between scale and being realistic– Inter-domain Level:

• BRITE: 15 ISPs, BA method– Intra-domain Topology:

• Embedded 6 Rocketfuel Maps• BFS Based Bandwidth Estimation: Higher Core Capacity

• Traffic Matrix– Gravity Model: Node Locations, City Populations

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• Realistic Simulation requires– Realistic ISP Topology

• Adjacency Matrix (Given by Rocketfuel Data)• Link Delays & Weights (Given by Rocketfuel Data)• Link Capacities (We have to model)• Edge and Backbone Router Classification (We have to model)• Routing Matrix (Path calculated by Shortest Path Algorithms,

as OSPF does)– Realistic Traffic Model

• Traffic Matrix Estimation(We have to model)

Network Model

BFS Based Link Capacity Estimation1) Select Most Connected Router2) Initiate a BFS3) Assign higher capacity to links

closer to center

• DC. BFS Dist = 2

• Atlanta BFS Dist = 3

1 2 3 4 5 6 7

40 gbps

10 gbps

2.5 gbps

640 mbps

155 mbps

45 mbps

10 mbps

Network Model

Network Model

24X2X

Gravity Model Based Traffic Estimation1) Determine Degree and BFS Distance Thresholds 2) Classify Edge / Backbone Routers3) Associate Area Population with Edge Routers4) Use Gravity Model to estimate traffic size

Seattle 6K

Chicago 3M NY 8M

Gravity ModelTraffic ~ Pop. 1 X Pop. 2

Evaluation• QoS

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Single-path vs. Multi-path Routing Increasing stability with longer timescales

Evaluation• Reachability

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Decreasing reachability with longer lease terms QoS vs Reachability tradeoff

Evaluation• Price Convergence

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Prices stabilization achieved at different paces

Evaluation• Path Stretch

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Path Stretch improves with longer contract term

Evaluation• Messaging Cost

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Messaging cost improves with longer contract terms

Conclusion• Contract Abstraction and Edge-to-Edge Design• Initial model to analyze

– Contract Routing Behavior– Contract Term Impact on Routing Performance

and Network Dynamics– Overlay Implementation and Transition Path

• Future Work– Developing methods to extend scale– Economic models and Game Theory

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Questions?

Thank You

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Net Neutrality• Incremental Deployment Scenario:

– Initial Phase: Complimentary market to packet switched Internet (i.e., contracts operating on left-over bandwidth capacities)

– Second Phase: Emergence of pure CS infrastructure owners and service providers

• Innovation driven at both edge and backbone• Analogy: co-existence of express and regular

mail

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End-to-end Connectivity• MPLS labels / GRE / IP-to-IP tunnels for edge-

to-edge– Minimal configuration burden on intra-domain

• Label Sharing / VPN / Tunneling at edge routers

• Establishing these states at edge routers and concatenation of edge-to-edge links to an end-to-end path through reservation

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Literature• Negotiation-based Routing• NIRA: User choice, Hierarchy, Addressing,

Multi-hop negotiation• Pathlet Routing: Economics?, Routing Protocol

Emulation on Pathlets• MIRO: Multi-path Routing• Path Splicing: Focus on reliability?• IPSphere, OpenFlow, Routing As a Service

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