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FIND PI Meeting, November 2007
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Value Flows and Risk ManagementArchitecture for Future Internet
Murat [email protected]
University of Nevada – RenoReno, NV
Aparna Gupta [email protected]
Shivkumar Kalyanaraman [email protected]
Rensselaer Polytechnic InstituteTroy, NY
Project Website: http://www.cse.unr.edu/~yuksem/contract-switching.htm
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Implied ChallengesMotivation Current architectural
problems: Users cannot express
value choices at sufficient granularity – only at access level
Providers do not have economic knobs to manage risks involved in
investing innovative QoS technologies and
business relationships with other providers
flexibility in time:
forward/option pricing
flexibility in space:
user-defined inter-domain
routes
capability to provide e2e
higher quality services
money-back guarantees,
risk/cost sharing
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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
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A Contract-Switched Network Core
Contracts: a practical way to manage “value flows”
Technologies to Support QoS
Economic considerations for service definition and delivery
Scalability, Efficiency and Fairness
Contract timescales Cost recovery Pricing the risk in QoS
guarantees Single-domain and
end-to-end contracts
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Basic Building Block: Intra-domain dynamic contracts
Contract components performance component, e.g., capacity financial component, e.g., price time component, e.g., term
Network Coreaccessed onlyby contracts
Cu
stom
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.
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Contract Link 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 for edge-to-edge (g2g) intra-domain paths
capability of managing value flows at a finer granularity
than point-to-anywhere deals
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How to achieve e2e QoS? Contract Routing:
Compose e2e inter-domain “contract paths” over available contract links satisfying the QoS requirements
Calculate the contract paths by shortest-path algos with metrics customized w.r.t. contract QoS metrics
Two ways: link-state contract routing at macro time-scales path-vector contract routing at micro time-scales
Monitor and verify that each ISP involved in an e2e contract path is doing the job
Punish the ISPs not doing their job, e.g. as a money-back to the others involved in the e2e contract path
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8Link-State Contract Routing: Macro-level, proactive
User X
2
3
5
ISPA
ISPC
ISPB
1
OwnerISP
Link QoS Term OfferedAfter
Price
A 1-2 10Mb/s 2hrs 1hr $10
A 1-3 40Mb/s 5hrs 15mins $80
B 2-4 100Mb/s 3hrs 2hrs $110
C 3-5 20Mb/s 1hr 30mins $8
C 4-5 60Mb/s 1day 5hrs $2504
Most cost-efficient route
Max QoS route
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9Path-Vector Contract Routing: Micro-level, on-demand, reactive
Provider initiates…
User X
2
3
5
ISPA
ISPC
ISPB
1 4
[C, 5-4, 30Mb/s,
45mins, $9]
[C-B, 5-4-2, 20Mb/s, 45mins, $6+$5]
[C-B-A, 5-4-2-1, 20Mb/s, 30mins, $7.3+3]
[C, 5-3, 10Mb/s, 30mins, $5]
[C-A, 5-3-1, 5Mb/s, 15mins, $1.25+$1.2]
pathannouncement
path
announcement pathannouncement
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FIND PI Meeting, November 2007
10Path-Vector Contract Routing: Micro-level, on-demand, reactive
User initiates…
User X
2
3
5
ISP A
ISPC
ISPB
1 4
[5, A-B, 1-2-4, 15-20Mb/s, 20-30mins, $4]
[5, A, 1-2, 15-30Mb/s, 15-30mins, $8]
[5, 10-30Mb/s, 15-45mins, $10]
[5, A, 1-3, 5-10Mb/s, 15-20mins, $7]
Paths to 5 are found and ISP C sends replies to the user with two specific
contract-path-vectors.
path request path request
path request
[A-B-C, 1-2-4-5, 20Mb/s, 30mins]
[A-C, 1-3-5, 10Mb/s, 15mins]
Paths to 5 are found and ISP C sends replies to the user with two specific
contract-path-vectors.
replyreply
reply
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11Putting it together: Contract routing + Financial engineering
End-to-end QoS services
Contract Routing Pricing Risk management
tools Spot contracts Forward contracts Options on Forward
Flexibility to innovate services
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Contingent-claim Pricing of Contracts
Outcomes of a fundamental risk N outcomes
Market’s collective view of current worth of future outcomes
Contingent Claim pays off should a specific outcome be realized in future
i – Price of a contingent claim, i Current value of a pay-off obtained
should outcome i be realized in future Price of a complex payoff(V) = .
V In continuous setting – state price
density
[1, 0, .., 0]
[0, 1, .., 0]
[0, 0, .., 1]
[1, , .., ]
.
.
.
.
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Single-domain QoS Contract Pricing and Money-back
Pricing Advertisable Contracts: with focus on
Cost recovery Congestion sensitive Promoting utilization
Pricing QoS Guarantees: applies financial engineering technique
Uses state-price density or contingent claims for underlying risk
Money-back Guarantees: for advertisable contract
Utilizing risk pooling concepts of insurance benefits
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Temporal Extensions of Single-domain QoS Contracts
Bail-out Forwards: on advertisable spot contracts
between peering/edge points i and j of an ISP
with flexibility of advertising different forward prices for edge-to-edge (g2g) intra-domain paths
Forwards with provision for Bail-out conditioned on network congestion
Spot and Forwards concatenated to create long-term contracts
Time
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Spatial Composition for End-to-end QoS Contract Pricing
Macro-level Contracts: centralized concatenation of contract links
Globally optimal path between a source-destination (s-d) pair
Optimize for price given required QoS characteristics and contract duration
Micro-level Contracts: decentralized concatenation of contract links
Locally optimal short-term concatenation of contract links
Constrained to satisfy QoS requirements
S
D
Micro-levelService
Macro-levelService