In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf ·...
Transcript of In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf ·...
![Page 1: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/1.jpg)
In Search of InterestingVANET Theory Problems
Calvin Newport
TDS Seminar
October 16, 2009
Newport VANET Theory
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Outline
Newport VANET Theory
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A VANET Primer
Newport VANET Theory
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What Makes VANETs Interesting
A VANET is a type of MANET in which the mobile nodes arevehicles. The intended communication is vehicle to vehicle, andvehicle to static roadside equipment.
Newport VANET Theory
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What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 6: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/6.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 7: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/7.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 8: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/8.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 9: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/9.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 10: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/10.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 11: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/11.jpg)
What Makes VANETs Interesting
Where as general MANETs are difficult to program, VANETs haveseveral features that simplify matters:
I Vehicles move in more predictable fashion.
I Mobility parameters are constrained.
I Interaction with roadside equipment is predictable.
I Portability issues are not a problem (computational power,energy, antennas, etc.)
I Location information can be assumed.
Newport VANET Theory
![Page 12: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/12.jpg)
VANET Problems
I 1 : Ideas validated with simulation.
I 2 : Simulation issues.
I 3 : Security issues.
I 4 : Measurements from real deployments.
I 5 : Analytic modeling.
I 6 : Optimization.
Newport VANET Theory
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VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 14: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/14.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 15: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/15.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 16: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/16.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 17: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/17.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 18: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/18.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 19: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/19.jpg)
VANET Problems
Big Issues...
I Data dissemination (and aggregation).
I MAC protocols.
I “Drive-Thru Data Access.”
I Building better simulations.
I Security and privacy.
I Network design issues: bitrate; power; etc.
Newport VANET Theory
![Page 20: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/20.jpg)
My Project
Big Picture Goal: Construct a citywide wireless mesh that usescars to transfer data between access points.
Newport VANET Theory
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My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 22: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/22.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 23: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/23.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 24: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/24.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 25: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/25.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.
I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 26: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/26.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.
I Etc.
Newport VANET Theory
![Page 27: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/27.jpg)
My Project
Near Future Goal: Explore the feasability of such meshes.
I Gather extensive pairwise connectivity data from mid-sizeddeployment.
I Build and validate connectivity model.
I Combine model with large-size traffic traces to determine:
I Conditions of connectivity.I Performance of various mesh strategies.I Etc.
Newport VANET Theory
![Page 28: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/28.jpg)
The Question Before Us
The Question Before Us: What interesting and useful theoryproblems related to VANETs remain to be solved?
Newport VANET Theory
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A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Newport VANET Theory
![Page 30: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/30.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Problem: How do we build an efficient system for aggregatingobservations in a VANET (e.g., free parking spaces or trafficdensity).
Newport VANET Theory
![Page 31: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/31.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Problem: How do we build an efficient system for aggregatingobservations in a VANET (e.g., free parking spaces or trafficdensity).
Solution: Use Flajolet-Martin sketches for simple, duplicationinsensitive, probabilistic approximations.
Newport VANET Theory
![Page 32: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/32.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 33: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/33.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.
I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 34: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/34.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 35: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/35.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 36: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/36.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 37: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/37.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 38: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/38.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Flajolet-Martin Sketches
I S = s1, ..., sw , si ∈ {0, 1}.I Geometric bit hash h, P(h(x) = i) = 2−i .
I To add element x , set sh(x) = 1.
I Let Z (S) describe position of final 1 in initial uninterruptedseries.
I C (S) = 2Z(S)
ρ , is a pretty good estimate of unique elementsadded. (Regardless of duplicate estimates).
I Can merge with bitwise-or.
Newport VANET Theory
![Page 39: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/39.jpg)
A Sampling of Existing VANET “Theory”
C. Lochert, B. Sheuermann, M. Mauve. ProbabilisticAggregation for Data Dissemination in VANETs. VANET,2007.
Newport VANET Theory
![Page 40: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/40.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 41: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/41.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 42: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/42.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 43: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/43.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 44: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/44.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 45: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/45.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory
![Page 46: In Search of Interesting VANET Theory Problemsgroups.csail.mit.edu/tds/seminars/f09/TDSVanet.pdf · What Makes VANETs Interesting A VANET is a type of MANET in which the mobile nodes](https://reader034.fdocuments.net/reader034/viewer/2022051602/5b2753927f8b9aae628b5045/html5/thumbnails/46.jpg)
Some Rough Ideas for New Directions...
I Distributed algorithms in settings with highly-dynamicmembership.
I What can we prove in shift-graph models?
I Model mobility with: G = (V ,E ), andp : E × N → P({1, ..., n}).
I Processes mapped to same or neighboring edges cancommunicate.
I Bound mobility with bounds on p. (e.g., can shift only toadjacent edges; a lower bound on dwell time before shiftingagain.)
I What connectivity properties can be proved aboutVANET-stye communication graphs?
I ???
Newport VANET Theory