Economics of Shared Data Plans

Soumya SenCarlee Joe-Wong

Sangtae Ha

Issue: Sustainability

e-commerce

cloud services

m-commerce

GoogleAmazonAppleMicrosoftFacebook

wired

wireless

AT&TVerizonT-MobileSprintComcast

Issue: Demand Growth

Issue: Viability

• Spectrum Crunch• 108% Growth• Data Caps

Trends: Pricing Evolution

Trends: Shared Data Plans

Perspectives & Questions

• Is a shared data plan always better?• How to fairly share data across users?

• How to price shared data plans?• How many shared plans to offer?

Consumers Service Providers

Shared PlansDevice 1 Device 2

• Entertainment & Productivity device

• Child’s & Parent’s device

Shared Plans

• Devices have different marginal value for consumed bandwidth (v1, v2)

• Usage distribution: fi(ci), demand ci

• Different max usage (C1max, C2

max)

Device 1 Device 2

Shared Plans

• Entertainment & Productivity device– v1 < v2, C1

max > C2max

• Child’s & Parent’s device– v1 < v2, C1

max < C2max

Device 1 Device 2

Shared Data Plan Pricing

• Per device fee (by device type): g1, g2

• Bandwidth Caps: B1, B2, Bs

• Tiered (approximates usage pricing $10/GB):– {p1, p2} < ps (in $/GB up to cap)

• Overage fees: {o1, o2} < os (in $/GB above cap)

Devices Monthly Line Access (per device)

Smartphones $40

Basic Phones $30

Jetpack/Netbooks/Notebooks/USBs $20

Tablets $10

Overage Scenarios

• Demand loss above cap• Quality degradation, throttling above cap• Self-restraint by users on lower utility device• α of overage demand is lost

• Usage loss from lower valued (v1) device

3- Stage Model

Assumptions (relaxable): • Continuum of data caps to choose from• Log utility function: Ui=vi log(1+ci)-piBi

Choose between shared and individual

Data plans

Choose the data capfor the chosen plan

Adjust for usage loss(if needed) and

incur overage fees

Demand for data on each device

is realized

Direction of solution

Analysis: Individual Data Plans

• Compute (B1*, B2

*) and (U1*, U2

*)

User utilities:

Expected utility:

Analysis: Shared Data Plan (1)

Relationship between data cap, realized demand, and usage loss in overage regime

c2

c1

(c1, c2)

Case 2:

No demand loss

c2

c1

(c1, c2)

Demand loss

Case 1: c2

c1

(c1, c2)

Demand loss

Case 3:

Analysis: Shared Data Plan (2)• Shared plan allows

adjustments across devices

• Compute Bs*, Us

* in each region and select the best option

• Use E(Us*), E(U1

*+U2* )

to choose shared vs individual data plans

Example Usage Stats

• 19 iPhone, 15 iPads• iPad users: β~(0.348, 0.408)• iPhone users: β~(0.515, 0.191)

Consumer Choice: Non-trivial

Indv. Indv.

Shared

Correct choice of shared or individual plan depends on demand loss in overage regime due to behavioral factors (user’s self-restraint) and technological factors (performance degradation from throttling)

Robustness: Tiered Data Plans

Consumer choice can be even more complicated for tiered data plans

Indv.

Indv.

Shared

Shared

The budget choices are B1 = 0.2, 1 and B2 = 0.5, 1.5 (in GB)

Future Directions

• Is a shared data plan always better?• How to fairly share data across users?

• How to price shared data plans?• What shared data caps to offer?

Consumers Service Providers

“Fair” sharing• Build “fairness” into the system• Allow “priorities”• Use dynamic planning to increase “efficiency”

40%

35%

25% 20%

48%

33%

Alice

Bob

Chris

Chris

Empowering Consumers

Daily allocationby users

+Usage alerts

Fair allocation by apps

+Usage alerts

Set cap. Set priority.

priority=1 Priority=2

ChrisAlice

Trial App GUIs

Personal Usage MonitoringShared Usage Monitoring Shared Usage Prediction

References• Innovating Access Pricing

– http://www.datami.com

• Industry-academia collaboration– http://scenic.princeton.edu/SDP2012/

• SDP 2013 (Workshop on Smart Data Pricing)– co-located with IEEE INFOCOM 2013, Turin, Italy

• DataWiz (free iOS & Android mobile app)– scenic.princeton.edu/datawiz/

Questions?Thank you!