Challenging the Monopoly of Mobile Termination Charges with an Auction-based Charging and User-centric System (AbaCUS)

1. NetSys 2013 Stuttgart
March 13, 2013
Challenging the Monopoly of Mobile Termination Charges with an
Auction-based Charging and User-centric System (AbaCUS)
Christos Tsiaras, Burkhard Stiller
Department of Informatics IFI, Communication Systems Group CSG,
University of Zürich UZH
[tsiaras|stiller]@ifi.uzh.ch
Background
High level architecture
The AbaCUS protocol
The AbaCUS main components
Summary
Future work
© 2013 UZH, CSG@IFI 1

2. Background
termination rate
Home MNO Competitive MNO
MTR
q Voice service consumer Regulator
MNO
Call termination
X
service
– Caller
– Callee Callee
MSISDN
q Voice service price schema Contract
– The caller's provider fee
– Mobile Termination Rate (MTR) The termination rates I need a new contract!
has been raised? Termination rates?
q MTR is a monopoly Why do I care? What is this?
– Only home MNO can terminate calls
Call initiation
– Voice service consumers does not service
consider the termination rate before
establish a contract
– MTR raise does not affect MNOs MNO VoIP
FNO
– MTRs are being regulated
Caller
© 2013 UZH, CSG@IFI 2

3. AbaCUS high level architecture
Callee (MSISDN)
q The caller can reach the callee
Home MNO Competitive MNO
through his home MNO
q The callee could be reached by
any MNO
– A virtual MSISDN would be needed Au2
q An Auction Authority (Au2) will TeR-C
demand
define which MNO will terminate
the call Dial the
MSISDN Dial a
QoS-C virtual
– The call termination service request demand MSISDN
parameters are defined by the Quality
of Service Class (QoS-C)
– The price for the call termination
service is defined by the Termination MNO VoIP
Rate Class (TeR-C) FNO
– The winning MNO decision is made
through an auction Caller
© 2013 UZH, CSG@IFI 3

4. The AbaCUS protocol
Caller Callee Au2 MNO1 MNO2
Update TeR-C / location & QoS-C
1: Callee Data (CD) Periodic
ACK Updates
2: Response
Update TeR-C / location & QoS-C
ACK
3: Service request
4: Notify
5: Free to register
6: Register
7: Ready to call
AbaCUS auction traffic
8: Place a call AbaCUS protocol traffic
Mobile telephony traffic
© 2013 UZH, CSG@IFI 4

5. Quality of Service Classes (QoS-Cs)
q Defines a service request
q QoS
– Call set-up priority
– Sound quality
QoS-C Call set-up priority Maximum sound quality expected
Critical 1st Maximum
Excellent 4th Maximum
Important 2nd High
High 3rd High
Normal 5th Good
Medium 6th Good
Low 7th Good
Best-effort 8th Low with possible disconnections
Fault-tolerant 9th Low with possible disconnections
Poor 10th Low with disconnections expected
© 2013 UZH, CSG@IFI 5

6. Termination Rate Classes (TeR-Cs)
q Defines the price for the requested service
– Call set-up price
– Call rate
– Virtual dial-in numbers
TeR-C Call set-up price Rate
Premium Standard Premium
0900 xyz vwz VIP Standard High
Gold Standard Normal
Silver - High
Virtual dial-in
Bronze - Normal
Numbers 11 xyz Economy - Low
(MSISDNs)
Low Standard Low rate after the 3rd minute
Budget Low Low rate after the 3rd minute
Special Standard -
0800 xyz vwz Free Low -
© 2013 UZH, CSG@IFI 6

7. The AbaCUS auction (1)
1st bid 2nd bid Winning bid
Vickrey’s auction
Bidders: consumers
Auctioneer: seller Winning bid: higher
Price: next lower bid
AbaCUS auction TeR-C5 TeR-C5 TeR-C5
TeR-C4
Bidders: MNOs Winning bid: lower
Auctioneer: “caller” (Au2) Price: next higher bid
if next higher bid = lower bid + 1
TeR-C5 TeR-C5
TeR-C4
TeR-C3 TeR-C3
Winning bid: lower
Price: lower bid
if next higher bid > lower bid + 1
© 2013 UZH, CSG@IFI 7

8. The AbaCUS auction (2)
Last two non draw winners history
w1 MNO1
All AbaCUS auction results w2 MNO1
Auction # Winner Draw case
1 MNO1 ✗
2 MNO1 ✗
3 MNO1 ✔ Draw winners history
4 MNO1 ✔
Draw # Winner
5 MNO2 ✔
1 MNO1
2 MNO1
3 MNO2
© 2013 UZH, CSG@IFI 8

9. AbaCUS Auction Evaluation
q Honest bids incentive
– A winning bid can still be rejected if it is higher than the user’s threshold
– A winning bid increases the MNO's chances to win a future auction in
case of a draw
• Only the non-draw and the non-rejected winning bids are taken in to consideration
– The winning bidder has a chance to receive a higher TeR-C than the
originally requested one
– The second higher bid will be chosen IFF it is higher at most by one
respective TeR-C
• “Winner-blocking” is not allowed. A bidder is not motivated to place high bids in order to
force the caller to reject the second higher bid, which will be proposed to the caller
q Prisoner's “honest dilemma”
– The bidder is honest (H)
– The bidder is lying (L) MNO1-MNO2 L-L L-H
MNO1-MNO2 H-L H-H
© 2013 UZH, CSG@IFI 9

10. Auction Authority (Au2)
q The area is divided in to grids Au2
q The Au2 receives from the
MNOs their bid per QoS-C
and grid periodically
q The winning bid per QoS-C,
grid, and period is calculated High request
Gold tolerance MNO1:
High → Gold
q When a caller sends a request Normal → Free
MNO2: High → Bronze
to the Au2 the precalculated High request Normal → Low
winning bid is proposed to the Free tolerance
caller
q The Au2 will reject the MNO's
offer if it is higher than the
caller's tolerance
© 2013 UZH, CSG@IFI 10

11. Stakeholders
MNO’s
& MVN
O’s su
bs cribers
Regulator
tors Caller
Network opera Callee
MNO MVNO
Social networks Au 2
Au 2 p
rovide
r
Legal relation
Economic relation
© 2013 UZH, CSG@IFI 11

12. Summary
q MNOs subscribers
– The caller sets his preference
– The caller can influence the final price of the call
q MNOs
– Potential infrastructure maximization
– QoS-guarantee services offer is possible
q Regulators
– Low MTRs regulation demand
– Dynamic, live, and on-demand MTRs competition
© 2013 UZH, CSG@IFI 12

13. Future work
q System evaluation in a simulated environment
q Protection mechanism in case that a user pay for a
QoS-C but never received it
– QoS monitoring/measuring mechanism
• Rely on caller's/callee's honesty?
q System prototyping
q Accounting mechanism for call related data
q Efficiency of such a system in other markets
– Fixed telephony
– VoIP
© 2013 UZH, CSG@IFI 13

14. Q&A
Thank you!
© 2013 UZH, CSG@IFI 14