Post on 11-Jan-2016
description
Two-Market Inter-domain Bandwidth Contracting
Anusha Uppaluri, University of Nevada, Reno(anusha.uppaluri@gmail.com)
Praveen Kumar, Rensselaer Polytechnic Institute Murat Yuksel, University of Nevada, Reno
Aparna Gupta, Rensselaer Polytechnic InstituteKoushik Kar, Rensselaer Polytechnic Institute
Industrial Engineering Research Conference, IERC, 61st Annual Conference & Expo, Reno, Nevada, May 21-25, 2011.
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Overview• Introduction• Problem Formulation
– Network Model– Single Edge – to – Edge Contract Link– Multiple Edge – to – Edge Contract Links
• Simulation Experiments– Single Edge – to – Edge Link– Multiple Edge – to – Edge Links
• Network Setup• Results
• Conclusion and Future Work
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Introduction
• Migration of data rich applications indicate that the increasing demand for bandwidth is unlikely to vanish
• Managing bandwidth allocation to customers presents a major challenge and received a lot of attention
• Many approaches involving advanced techniques for achieving efficient contracting among ISPs have been explored
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Introduction (contd..)
• Crucial handicap of existing inter – ISP economics is coarse granularity of contracts
• Precursor to realization of more dynamic & automated contracting is sufficient motivation for ISPs to invest and install necessary tools & protocols
• Question focused on : how much benefit there is if the contracts were classified into simple two market regime, highly dynamic and long time scale durable
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Introduction (contd..)
• Also, an important issue is the management of risks in ISPs investments
• Though an automated and dynamic way of establishing contracts will enable ISPs to flexibly allocate their resources several questions arise:– When and where to advertise a new contract– How to assess the risks involved and reflect
them on contracting parameters – How to divide links between different types
of contracts
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Introduction (contd..)
• Model and formulate revenue maximization problem by considering the constraints imposed by correlation among contract links
• Through a detailed simulation several insights on optimal reservation levels for the two types of contracts are provided
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Problem formulation
Contract switched Internet architecture considered7
Problem formulation(contd..)
• Edge – to – edge contract links are advertisable contracts between pairs of ingress and egress routers
• The Capacity of a contract link is equal to the minimum of the capacities of the physical links used to construct the contract link
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Problem formulation(contd..)
• Capacity of the contract links must be segmented between short – term and long – term contracts
• There is enough demand for long – term contracts while the demand for short – term contracts is stochastic
• Revenue from unit demand for short – term contracts per unit time is higher than Revenue from unit demand for long – term contracts per unit time
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Single Edge- to- Edge Contract Link
• Single edge – to – edge contract link is considered• Enough demand for long – term contracts is
assumed. Bandwidth allotted for long – term contracts is always used
• Bandwidth available for short – term contracts may or may not be used
• ISP must choose optimal value for bandwidth reserved towards long – term contracts so that total expected revenue per unit time is maximized
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•
Single Edge- to- Edge Contract Link(contd..)
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Revenue obtained from long - term
contracts per unit time
Revenue obtained from short – term contracts per unit
time
Bandwidth reserved for long – term
contracts
Capacity of the contract
link
Multiple Edge- to- Edge Links
• Assuming several edge – to – edge links in ISP’s network
• Edge – to – edge contract links share physical links which impose constraints on bandwidth reserved for long – term contracts of these contract links
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•
Multiple Edge- to- Edge Links (contd..)
Bandwidth reserved for long –
term contracts
Capacity of the physical links used to construct the
contract link
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•
= Revenue form long term contracts per unit time
Multiple Edge- to- Edge Links (contd..)
Revenue from long –term
contracts per unit time
Sum of revenue obtained from long term
contracts on multiple contract links
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•
Multiple Edge- to- Edge Links (contd..)Revenue
obtained from short term
contracts per unit timeMinimum of
Short term demand and
residual capacity
Reservation for short – term contracts on contract linkReservation for short – term
contracts on a contract link
Remaining capacity of
physical link l
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Multiple Edge- to- Edge Links (contd..)
•
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Revenue from long – term
contracts per unit time
Revenue from short – term contracts per
unit timeBandwidth reserved
towards long term contracts
Capacity of contract link
Bandwidth reserved for long –
term contracts
Capacity of the physical links used to construct the
contract link
Simulation Experiments
Single edge – to – edge link• Capacity of single edge – to – edge contract link is
set to 10• Two distributions of short term demand
– Uniform distribution between 0 and 10– Truncated Gaussian distribution in the interval
[0,10] with mean 5 and standard deviation 1
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Simulation Experiments(contd..)
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Optimal long term reservation on contract link is shown. PL is increased from 0 and PS is fixed at 10
Optimal long term reservation on
contract link on Y-axis
PL is being increased from 0 to
10 on X-axis
Graph for truncated Gaussian
distribution
Graph for uniform
distribution
Multiple Edge – to – Edge Links
Network Setup• Real topology map of GEANT ISP with 23 routers
is used. 3 ingress & 3 egress routers are chosen. Nine edge- to- edge contract links are considered
• Capacity of physical links is set to 10 and so the capacity of contract link (Bie) is 10.
• Short term demand is taken to be uniformly distributed between 0 and 10
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Results
Maximum total revenue, maximum long term revenue and maximum short term revenue are shown. PS is set to 10
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PL is being increased
from 1 to 10 on X-axis
Maximum total revenue on Y-
axis
PL≤5 then PL is not high enough to
generate significant long term revenue
PL>5 then long – term contracts
generate higher revenue
Optimal reservation levels on nine links when PL=5 and PS=10 & PL=10 and PS=10
Results(contd..)
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PL=5 and PS=10 PL=10 and PS=10
Contract links listed on X- axis
Contract link capacity on Y-axis
Contract links listed on X- axis
Contract link capacity on Y-axis
Increasing PL increases long -
term reservation levels
Long term reservation levels on 1,6,7 remain zero at all times
Conclusion and Future Work
• Revenue maximization problem was formulated for an ISP which wants to participate in two segments of bandwidth markets
• The level and distributional characteristics of short – term demand and interactions among contract links are key determinants
• In the future, possibility of multiple paths underlying a given single contract link instead of single path will be considered
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Queries?
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