Edge-to-Edge Bailout Forward Contracts for Single-Domain Internet

Services

Weini Liu, Rensselaer Polytechnic InstituteHasan Karaoglu, University of Nevada, Reno

Aparna Gupta, Rensselaer Polytechnic InstituteMurat Yuksel, University of Nevada, Reno

Koushik Kar, Rensselaer Polytechnic Institute

MotivationISPs can provide single domain QoS for wide range of applications Video-conferenceOnline Video GamesStreaming Live Media, name it

Motivation

There is no easy way to : express QoS demand to intermediate providers exchange QoS service capabilities and offers to other providers

?

Motivation• Current architectural

problems:– Providers do not have

economic knobs to manage risks involved in

• investing innovative QoS technologies and

• business relationships with other providers

Users cannot express value choices at sufficient granularity – only at access level

Implied Challenges

flexibility in time:

forward/option pricingflexibility in space:

user-defined inter-domain

routes

capability to provide e2e

higher quality services

money-back guarantees,

risk/cost sharing

Intra-domain Dynamic Contracts

Network CoreCustom

ers

EdgeRouter

EdgeRouter

EdgeRouter

EdgeRouter

EdgeRouter

EdgeRouter

Stations of the provider computing

and advertising local prices for edge-to-

edge contracts.

Stations of the provider computing

and advertising local prices for edge-to-

edge contracts.

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

Contract Switching Paradigm

7

Contract-switching: A paradigm shift…

Circuit-switching

Packet-switching

Contract-switching

ISPA

ISPC

ISPB

e2e circuits

ISPA

ISPC

ISPB routable

datagrams

ISPA

ISPC

ISPB contracts

overlaid on routable datagrams

SPOT, Forward and Bailout Forward Contracts

Well defined components (performance, financial and time) Time Duration for Contracts

Spot Contracts Providing the service in short term considering current market

conditions Forward Contracts

Providing the service at a future time for predetermined price Bailout Forward Contracts

Make forward contracts applicable to capacitated network resources

Atomic Short Medium Long

Bailout Forward ContractSingle g2g Contract

• Bandwidth guarantee as performance metric ( eg.100 Mbps )• Bandwidth threshold to activate bailout condition ( e.g.. 80 Mbps)• Exposed to variation on demand, bandwidth capacity and spot prices (e.g. For next five days, $0.25)

Bailout Forward ContractMultiple g2g Contracts

• Exposed to the additional effects of other traffic flows as a result of overlapping links with other g2g overlay paths

• How we model this interaction ?

Intensity of Overlap

Link Capacity 1.5 gbpsUtilization = 10%

Link Capacity 0.3 gbpsUtilization = 50%

Flow1 50 mbps

Flow2 100 mbps

Performance

• Can an ISP survive by applying BFC approach ?– How frequent does BFC bailout ?

• BFC Robustness against – increasing demand ? (demand)– decreasing available bandwidth ? (supply)– major link failures ?

– How efficient is BFC pricing ?• Revenue Losses

Network Model• 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 ModelBFS 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 6 740 gbps

10 gbps

2.5 gbps

640 mbps

155 mbps

45 mbps

10 mbps

Network Model

24X2X

Gravity Model Based Traffic Estimation1)Determine Degree and BFS Distance Thresholds 2)Classify Edge / Backbone Routers3)Associate Area Population with Edge Router s4)Use Gravity Model to estimate traffic size

Seattle 6K

Chicago 3M NY 8M

Gravity ModelTraffic ~ Pop. 1 X Pop. 2

Network ModelSummary :I. Construct Routing Matrix RnXn

I. Using Adjacency Matrix A and Weight Matrix W given by Rocketfuel Topologies

II. Apply Dijktra’s Shortest Path AlgorithmII. BFS Based Link Capacity EstimationIII. Form the Traffic Matrix TnXn using Gravity ModelIV. Calculate traffic load on each link

I. If link capacity is less than traffic load, upgrade link capacity

Simulation Setup – Multiple BFC’sFailure Mode 1-2-3

• One of the most heavily loaded link is failed• Traffic passes through failed link is rerouted• Bandwidth share and correlation between traffic flows also changes

Simulation Results – Single BFC

Simulation Results– Single BFC

Path Forward Prices E[ST] Probability

{ST>F} Probability

{AT<Th}

1 0.20609 0.20305 0.502 0.092 0.27162 0.24982 0.449 0.0653 0.21293 0.21213 0.486 0.0794 0.25039 0.24825 0.477 0.0945 0.22177 0.21211 0.465 0.093

Threshold = 15th percentile

Results for five sample g2g contracts

Simulation Results– Multiple BFCs

Mean fraction 16.4 %

Simulation Results– Multiple BFCs

Simulation Results– Multiple BFCs

Simulation Results– Multiple BFCs

Simulation Results– Multiple BFCs

Simulation Results– Multiple BFCsCase Expected

Revenue Fraction of Bailouts

Artificial No Bailout or Failure 95.7464 0

Base Case (No Failure) 80.43655 0.16403

Failure Mode 1 78.98833 0.16505355

Failure Mode 2 81.34074 0.163980954

Failure Mode 3 80.98213 0.16676308

Network Analysis

Mean fraction 27%

Summary• Single domain edge to edge path abstraction

– Domain is a set of G2G overlay paths– Flexibility to price each G2G path individually

• Bailout Forward Contract with Bandwidth Guarantees – Bandwidth threshold as Bailout clause– Money-back guarantees

• BFC’s are robust against link failures, fluctuations in demand, supply and correlation effects between traffic flows

Future Work Conduct network analysis inter-domain e2e QoS

paths “Contract Paths” which are composed of edge to edge (g2g) intra-domain “Contract Links”

Study Economical and Technical Aspects of “Contract Switching Paradigm” Discovery of Better Alternative Paths Better network utilization Game Theoretical analysis of collaboration of ISPs

Questions ?

• Value Flows and Risk Management Architecture for Future Internet

• Project Website– http://www.nets-find.net/Funded/ValueFlows.php– http://www.cse.unr.edu/~yuksem/contract-switching.htm

– Or google “Contract Switching”