Loading in 5 sec....

Interference-Aware Fair Rate Control in Wireless Sensor Networks (IFRC)PowerPoint Presentation

Interference-Aware Fair Rate Control in Wireless Sensor Networks (IFRC)

- By
**skule** - Follow User

- 130 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about ' Interference-Aware Fair Rate Control in Wireless Sensor Networks (IFRC)' - skule

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

### Interference-Aware Fair Rate Control in Wireless Sensor Networks (IFRC)

### Backup Slides Structural Vibrations

Sumit Rangwala

Ramakrishna Gummadi, Ramesh Govindan, Konstantinos Psounis

Wireless network of N nodes Networks (IFRC)

Data transmission over multiple hops to a single node

“Design a distributed algorithm to dynamically allocate fair and efficient rate to each flow”

f11

f13

f15

f19

f20

Problem DefinitionNeighbor

10

11

12

13

14

15

17

18

19

16

20

21

Motivation: A Wireless Sensor Network for Collecting Structural Vibrations

- Nodes measured vibrations and transmitted it to a central node
- Over multiple hops

- Preconfigured rates for each flow
- Led to congestion
- More than an hour to receive 10 min of vibration data in a 15 node network

- Led to congestion

f Structural Vibrations11

f13

f15

f19

f20

AssumptionsNeighbor

- CSMA MAC (without RTS/CTS)
- Link-layer retransmissions
- Routing Tree
- One flow originating per node

10

11

12

13

14

15

17

18

19

16

20

21

Assumptions consistent with current practice in sensornets

f Structural Vibrationsi

fj

Challenges- Goal
- Max-min allocation

- Wireless Networks
- Transmission rate from a node to its neighbor depends on neighborhood traffic
- Flows affecting this transmission rate are not merely flows traversing a node.

A

m

n

B

Flows that affect each others' rate may not traverse a common link or node

Challenges Structural Vibrations

- Transmission rate along 16 →14
- Dependent on traffic on various other links
- 20 → 16, 21 → 16, 14 → 12
- 17 →14, 13 →11, 12 →10

- Dependent on traffic on various other links

10

Neighbor

- Transmission rate along 16 →14
- Dependent on traffic on various other links
- 20 → 16 (a) , 21 → 16 (b), 14 → 12 (c)
- 17 →14 (d), 13 →11 (e), 12 →10 (f)

- Dependent on traffic on various other links

- Transmission rate along 16 →14
- Dependent on traffic on various other links
- 20 → 16 (a) , 21 → 16 (b), 14 → 12 (c)
- 17 →14 (d), 13 →11 (e), 12 →10 (f)

- Dependent on traffic on various other links

- Transmission rate along 16 →14
- Dependent on traffic on various other links
- 20 → 16 (a) , 21 → 16 (b), 14 → 12 (c)
- 17 →14, 13 →11, 12 →10

- Dependent on traffic on various other links

Child/Parent

f

11

12

e

c

13

14

15

d

- The rate of flows traversing 16 →14 (flows from 20, 21, and 16)
- … is affected by rate of:
- Flows originating from 17, 14, 13, 12,
- As well as 15, 18, 19

- … is affected by rate of:

16

17

18

19

a

b

20

21

Definition: Potential Interferer Structural Vibrations

Interfering links

l1 interferes with a link l2 if transmission along l1 prevents

- initiation of a transmission along l2 or
- successful reception of a transmission along l2.
Potential interferer

Node n1 is a potential interferer of node n2 if

- flow originating from node n1 uses a link that interferes with the link n2 → parent(n2).

10

Neighbor

Child/Parent

f

11

12

e

c

13

14

15

d

For CSMAand many-to-one traffic

potential interferer (ni) includes

- neighbors of ni
- neighbors of parent(ni)
- Descendents of all the above nodes

16

17

18

19

a

b

20

21

IFRC Design Structural Vibrations

- Congestion Detection
- Based on avg. queue length

- Congestion Sharing
- To all the potential interferers

- Rate Adaptation
- AIMD

rlocal (rate of flow from this node)

Forwarding Traffic

Queue at each node

Packet transmitted until queue is empty (with retransmission)

IFRC adapts rate of flow originating at a node,

not the rate of flows traversing the node

Congestion Detection and Structural VibrationsRate Adaptation

- Congestion Detection
- Based on queue length calculated as
qavg = wq * qinst + (1- wq) * qavg

- Thresholding

- Based on queue length calculated as
- Rate Adaptation
- Every 1/rate sec (Additive Increase)
rate= rate + δ/ rate

- On local congestion (Multiplicative Decrease)
rate= rate/2

- Every 1/rate sec (Additive Increase)

Congestion Sharing Structural Vibrations

- Each node piggybacks on every transmitted packet
- Its own rate (rlocal) and its congestion state
- Rate and congestion state of its most congested child

Congestion Sharing Structural Vibrations

Rule 1:

Local rate of a node should not be greater than that of its parent

(rlocal <rparent)

Rule 2:

For any congested neighbor or congested child of a neighbor

Local rate should not be greater than the rate of the congested node

(rlocal <rcongested node)

10

Neighbor

Child/Parent

11

12

13

14

15

16

17

18

19

20

21

These rules are sufficient to signal all potential interferers

Queue Threshold Structural Vibrations

Network size and topology

Avg. depth of the tree

Queue Threshold

Parameter Selection- Additive Increase
- δ = rate of increase

- Analytically characterize δ to ensure stability

32 Structural Vibrations

4

31

42

41

40

39

38

37

36

35

34

33

3

30

5

29

6

2

21

20

7

1

28

27

25

19

18

16

14

13

12

9

8

26

24

23

22

15

11

17

10

4th Floor

Evaluation on Sensor Testbed- Platform
- Tmote Sky
- TinyOS 1.1.15

- Setup
- 40 node testbed
- Network diameter = 8 hops

- Static routing tree
- Depth of the Tree = 9 hops
- Link quality varied from 66% to 96%

- 40 node testbed
- Each experiment was conducted for an hour

Base Station

Topology Structural Vibrations

Base Station

Per Flow Goodput and Structural VibrationsPacket Reception

Average goodput as well as the instantaneous goodput is fair

Comparison with Optimal Structural Vibrations

IFRC achieves 80% of the optimal fair rate

IFRC achieves 60% of the optimal fair rate

IFRC achieves 60-80% of the optimal fair rate

Rate Adaptation and Structural VibrationsInstantaneous Queue Length

Max Buffer Size = 64

Not a single drop due to queue overflow

Weighted Fairness Structural Vibrations

- IFRC works without modification
- Sending rate = weight* rlocalpkts/sec

w = 1

w = 2

w = 1

IFRC assigns rate proportional to node weight

Multiple Sink Structural Vibrations

- Two base stations rooted at 1 and 41
- Nodes get rates that are fair across trees

- IFRC is efficient
- Node 4,5 and 6 get greater (but equal) rates
- Their flows don’t traverse the most congested region.

- Node 4,5 and 6 get greater (but equal) rates

Conclusions Structural Vibrations

- Analysis of set of flows that share congestion at a node
- Potential interferers

- Design and implementation of low-overhead rate control mechanism
- Analysis of IFRC’s steady-state behavior
- Provide guidelines for parameters selection

Thank You Structural Vibrations

- For more Information
- http://enl.usc.edu/~srangwal/projects/ifrc.html

- Code
- Tinyos contrib
- tinyos-1.x/contrib/usc-ifrc

- ENL public CVS
- http://enl.usc.edu/cgi-bin/viewcvs/viewcvs.cgi/ifrc

- Tinyos contrib

Definition: Fair and Structural VibrationsEfficient Allocation

- fiflow originating from node i
- Fiflows routed through node I
- At each node i, define Ғito be the union of Fi and all sets Fj
- where j is either a neighbor of i, or a neighbor of i’s parent. These flows are flows from i’s potential interferers.

- Allocate to each flow in Ғia fair and efficient share of the nominal bandwidth B. Denote by fl,ithe rate allocated at node i to flow l.
- Repeat this calculation for each node.
- Assign to flthe minimum of fl,i over all nodes i.

10

Neighbor

Child/Parent

11

12

13

14

15

16

17

18

19

20

21

Sensornets Structural Vibrations

Graceful, fair, degradation under load [Hull et al. (Fusion), Wan et al. (CODA)]

Centralized rate allocation [Sankarasubramaniam et al. (ESRT), Ee et al.]

AIMD-based rate adaptation without congestion sharing [Woo et al.]

Wireless ad-hoc networks

Congestion sharing heuristics for any-to-any communication [Xu et al. (NRED)]

Related WorkUnlike prior work, we precisely identify the set of potential interferers

These heuristics don’t precisely identify the set of potential interferers

Congestion Detection Structural Vibrations

- Based on queue length calculated as EWMA
qavg = wq * qinst + (1- wq) * qavg

- Multiple thresholds
- Lower threshold L
- Upper thresholds U(k) = U(k-1) + I/2k-1
- U(0) = U

Local Congestion

L

U

U + I

U + 3I/2

Local Congestion

Rate Adaptation Structural Vibrations

- Slow start
- Starts with rate = rinit
- Every 1/ ratesec
- rate= rate + Φ

- Slow start ends when
- node itself get congested
- constrained by other nodes to reduce its rate
- Congestion sharing

every 1/r Structural Vibrationsi sec

ri = ri+δ/ri

ri = ri /2

ri = ri /2

ri = ri /2

L

U

U + I

U + 3I/2

every 1/ri sec

ri = ri+δ/ri

ri remains unchanged

Congestion Detection andRate AdaptationRate adaptation with changing queue size

Base Station Structural Vibrations

- Maintains rbase station, like rlocal of any other node, to share congestion across nodes
- Follows the same algorithm for rate adaptation with one exception
- Decreases rbase stationonly when a child of base station is congested.
- It does not decreases its rate when any other neighbor is congested or any child of a neighbor is congested.

- Decreases rbase stationonly when a child of base station is congested.

Parameter Selection Structural Vibrations(Steady State)

- Additive increase
- Constraint on ε
- U0 and U1 based on [Floyd et al.]
- Rule of thumb for Fj
- (n = size of network)

Evaluation (Tree) Structural Vibrations

Parameters Used Structural Vibrations

Comparison with Optimal Structural Vibrations

Max Queue Length

IFRC achieves 60-80% of the optimal fair rate

Node Addition Structural Vibrations

Nodes join

Node Deletion Structural Vibrations

Nodes leave

IFRC Structural Vibrations(No Link Layer Retransmissions)

Subset of node Structural Vibrations

- Special case of weighted fairness
- nodes with no data to send ≡ weight = 0

Multiple Sink (Trees) Structural Vibrations

Base Stations

Download Presentation

Connecting to Server..