Reliable QoS Routing in Ad Hoc Networks

1
Reliable QoS Routing in Ad Hoc Networks

• K.S. Chan
• EEE Department
• The University of Hong Kong

2
Outlines

• Introduction
• Bandwidth reservation
• Bandwidth measurement on link
• Reservation algorithm
• Multipath construction
• Performance evaluation
• Conclusions

3
Introduction

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm
• single path routing frequent interruption
• Best effort
• Multipath routing
• Multiple best-effort maximally disjoint paths
• Traffic distribution
• Video delivery with MDC

4
Introduction (contd)

• IETF drafts
• DSR Dynamic Source Routing

H
I
G
F
E
D
ABCD
A
C
B
A
AB
ABC
5
Introduction (contd)

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector

H
I
G
F
E
D
A C
A
C
B
A A
A B
6
Introduction (contd)

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector

H
I
G
F
E
D
A C
A
C
B
D B
A A D C
A B D D
7
Introduction (contd)

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm

H
I
G
F
E
D
A
C
B
8
Introduction (contd)

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm

H
I
D 1
D 2
G
F
D 2
E
D 3
D 1
D
D 0
A
C
B
D 3
D 2
D 1
9
Introduction

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm
• single path routing frequent interruption
• Best effort

10
Introduction

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm
• single path routing frequent interruption
• Best effort
• Multipath routing
• Multiple best-effort maximally disjoint paths
• Traffic distribution
• Video delivery with MDC

11
Multipath routing

• Multipath routing
• Multiple best-effort maximally disjoint paths

H
I
G
F
E
D
ABCD ABFGD AEFGD AEFID
A
C
B
A
AB
ABC
12
Introduction

• IETF drafts
• DSR Dynamic Source Routing
• AODV Ad hoc On-demand Distance Vector
• TORA Temporally-Ordered Routing Algorithm
• single path routing frequent interruption
• Best effort
• Multipath routing
• Multiple best-effort maximally disjoint paths
• Traffic distribution
• Video delivery with MDC
• No reservation

13
Introduction (contd)

• QoS routing
• CEDAR Core-Extraction Distributed Ad hoc Routing
• C. R. Lin JSAC 1999
• Multi-channel
• Single path
• C. Zhu infocom2002
• Single channel
• Single path

14
Introduction (contd)

• QoS routing
• CEDAR Core-Extraction Distributed Ad hoc Routing

D
C
B
A
15
Introduction (contd)

• QoS routing
• CEDAR Core-Extraction Distributed Ad hoc Routing
• C. R. Lin JSAC 1999
• Multi-channel
• Single path
• C. Zhu infocom2002
• Single channel
• Single path

16
Introduction (contd)

• QoS routing
• CEDAR
• C. R. Lin JSAC 1999
• Multi-channel
• The TSs available for both sending and receiving
  are the same
• Single path

0,1 2,3
F
2,3 4,5

D
E
A
B
C
4,5 6,7
6,7 0,1

Red used for sending information Blue used for
receiving information
17
Introduction (contd)

• QoS routing
• CEDAR
• C. R. Lin JSAC 1999
• Multi-channel
• Single path
• C. Zhu infocom2002
• Single channel
• Single path

0,1 2,3
F
2,3 4,5

D
E
A
B
C
4,5 6,7
6,7 0,1

Red used for sending information Blue used for
receiving information
Node B availaible for sending 0,1
available for receiving 2,3
18
Introduction (contd)

• Our scheme
• Single channel, frame-based ad hoc network
• Efficient bandwidth reservation
• Sequential multi-path set up

19
Link bandwidth measurement
0,1 2,3
F
2,3 4,5

D
E
A
B
C
4,5 6,7
6,7 0,1

Red used for sending information Blue used for
receiving information
What is the link bandwidth from node B to node C?
20
Link bandwidth measurement (contd)

• Some notations
• TK the set of time slots used by node K for
  transmission.
• RK the set of time slots used by node K for
  receiving.
• S the sample space of time slots.
• NK the set including all node Ks neighboring
  nodes.
• TStK the set of time slots available for
  transmission at node K. The transmission of node
  K in these time slots will not cause interference
  to other nodes current receiving.
• TSrK the set of time slots available for
  receiving at node K. The receiving of node K in
  these time slots will not be interfered by other
  nodes current transmission.

21
Link bandwidth measurement (contd)

• We have
• Then the link bandwidth from node i to node j is

TSij TSti ? TSrj
22
An example for the measurement
0,1 2,3
2,3 4,5
F

S0.. 7
D
E
A
B
C
4,5 6,7
6,7 0,1

TSrBS-TB-RB-TA-TE-TC0,1 TStBS-TB-RB-RA-RE-RC
2,3 TSrCS-TC-RC-TB-TD2,3 TSBC TStB ? TSrC
2,3
23
Bandwidth reservation over a path

• Information held on a node, node K
• TK, RK , TStK , TSrK , TSti , TSri , i? NK
• Initiated from destination
• Three cases
• Case 1 last link from source node, reserve on
  the link
• Case 2 the link next to the last reserve the
  timeslots not available on the last link
• Case 3 others, trying to reserve TSs not
  available on the links waiting for reservation

24
Bandwidth reservation algorithm
Algorithm When node i receives reservation
request from downstream node, node i-1 do
case 1 node i is source node m
reserve k timeslots from TSm,m-1 for link m?
m-1 END case 1   case 2 node i is the
node m-1

If S1gtk reserve k
timeslots in set S1 for link m-1?m-2 end case
2 else reserve timeslots in
S1 for link m-1?m-2 kk-S1 reserve k
timeslots for link m-1?m-2 from set
TSm-1,m-2 - S1 END case 2
25
Bandwidth reservation algorithm (contd)
case 3 other case let Pi be the set
containing node is neighboring nodes on path nm
to ni1 if
S1gtk reserve k timeslots
in S1 else
reserve all timeslots in S1, and let kk-S1

if S2gtk
reserve k timeslots in S2
else
reserve timeslots in S2 kk-S2
reserve k timeslots in
S3 END case 3
END do   disseminate the reservation information
to neighboring nodes node i passes the
reservation request to node i1 algorithm end.
26
An example for the algorithm
Demand reserve one timeslot on path A-B-C-D-E-F
0,1 2,3
TStA0,1,2,3,4,5 TSrA0,1,2,3,6,7 TStB2,3 T
SrB0,1 TStC4,5 TSrC2,3 TStD6,7 TSrD4
,5 TStE0,1 TSrE6,7 TStF0,1,2,3,6,7 TSrF
0,1,4,5,6,7
F
2,3 4,5

S0..7
(0,1)
D
(6,7)
E
(4,5)
A
B
(0,1)
C
(2,3)
4,5 6,7
6,7 0,1

27
An example (contd)
0,1 2,3
F
2,3 4,5
TSEF0,1 TSDE6,7 TSrB0,1 TSrD4,5

D
E
A
B
C
4,5 6,7
6,7 0,1

Step 1 node E reserve 1 TS for link E?F
Step1_1 choose TS not available on nodes B and D
for receiving, No Step 1_2 choose TS not
available on link D ? E 0,1 choose 0.
28
An example (contd)
0,1 2,3
F
0,2,3 4,5
TStB2,3 TSrB 0,1?1 TStE 0,1
?1 TSrE6,7 TStF 0,1,2,3,6,7
?1,2,3,6,7 TSrF 0,1,4,5,6,7 ?1,4,5,6,7
0
D
E
A
B
C
4,5 6,7
6,7 0,1

Step 1 node E reserve 1 TS for link E ? F
Step1_1 choose TS not available for nodes B and
D for receiving, No Step 1_2 choose TS not
available on link DE 0,1 choose 0. Step
1_3 disseminate this reservation.
29
An example (contd)
0,1 2,3
F
0,2,3 4,5
TSDE6,7 TSrC2,3
0
D
E
A
B
C
4,5 6,7
6,7 0,1

Step 1 node E reserve 1 TS for link EF TS
0 Step 2 node D reserves 1 TS for link DE
Step 2_1 choose TS not available on TSrC
6,7 choose 6
30
An example (contd)
0,1,6 2,3
F
0,2,3 4,5,6
0
TStD 6,7 ?7 TSrE6,7 ?7 TStF
1,2,3,6,7 ?1,2,3,7
D
E
A
B
C
4,5 6,7
6,7 0,1

Step 1 node E reserve 1 TS for link EF TS
0 Step 2 node D reserves 1 TS for link DE
Step2_1 choose TSs not available on TSrC
6,7 choose 6 Step 2_2 notify this
reservation
31
An example (contd)
0,1,6 2,3,4
TStA0,2,3,4,5 TSrA0,2,3,6,7 TStB3 TSrB0
TStC5 TSrC3 TStD7 TSrD5 TStE0 TSr
E7 TStF1,2,3,6,7 TSrF1,4,5,6,7
F
0,2,3 4,5,6
0
D
E
A
B
C
2,4,5 1,6,7
4,6,7 0,1,2
1
Step 1 node E reserves 1 TS for link EF TS
0 Step 2 node D reserves 1 TS for link DE TS
6 Step 3 node C reserves 1 TS for link CD TS
4 Step 4 node B reserves 1 TS for link BC TS
2 Step 5 node A reserves 1 TS for link AB TS 1
32
Reliability improvement

• Multiple maximally disjoint paths
• Erasure coding (Nn, m) for error recovery
• m slots per frame required, Km/n
• NgtK paths set up, each with n slots reserved
• Tolerate at most N-K paths breakdown

33
Sequential multipath setup

• Step 1 source S sends a flooding request to
  destination
• D only those links with
  sufficient bandwidth
• will forward the request
• Step 2 Node D chooses one path for reservation
• Step 3 Node S then initiates the second flooding
  to
• node D
• Step 4 Node D reserves bandwidth for the second
  path
• Step 5 go to step 3, until all N paths have been
  
• established

34
An example for multipath setup
H
I
0,1
6,7
2,3
G
F
7,8
E
2,6
0,1
D
4,5
1
4,5
A
0,1
1,2,3
C
B
Demand set up two paths from A? D, 2 timeslots
each path
35
An example for multipath setup
H
I
0,1
6,7
2,3
G
F
7,8
E
2,6
0,1
D
4,5
1
4,5
A
0,1
1,2,3
C
B
Demand Two paths from A-D, 2 timeslots each
path Step 1 Node A initiates flooding to node D
36
An example for multipath setup
H
I
0,1
6,7
2,3
G
F
7,8
E
6
0,1
D
4,5

4,5 4,5
A
0,1 0,1
1,2,3 2,3
C
B
Demand Two paths from A-D, 2 timeslots each
path Step 1 Node A initiates flooding to node
D Step 2 node D chooses path ABCD for
reservation (red reserved blue after
reservation)
37
An example for multipath setup
H
I
0,1
6,7
2,3
G
F
7,8
E
6
0,1
D
4,5

4,5
A
0,1
2,3
C
B
Demand Two paths from A-D, 2 timeslots each
path Step 1 Node A initiates flooding to node
D Step 2 node D chooses path ABCD for
reservation Step 3 node A sends the second
flooding
38
An example for multipath setup
H
I
0,1
6,7
2,3
G
F
7,8
E

0,1
D
4,5

4,5
A
0,1
2,3
C
B
Demand Two paths from A-D, 2 timeslots each
path Step 1 Node A initiates flooding to node
D Step 2 node D chooses path ABCD for
reservation Step 3 node A sends the second
flooding Step 4 node D chooses path AEHID for
reservation
39
Performance Evaluation

• Network simulator ns2
• Simulation area 720 m2 per node
• Frame 82ms, 50 timeslots
• Call arrival Poisson, 1 call per second
• Call holding time exponential, 20 seconds
• Each call 4 timeslots per frame required
• Erasure coding (6,4)
• Multipath 3 paths
• Simulation time 2500 seconds

40
Performance evaluation (contd)

• Moving pattern
• Random movement
• Initial position randomly chosen
• Random pause time
• For each node random destination, constant speed
  randomly chosen from 0, Max_speed
• Random pause at destination

41
Numerical results
Total number of connections supported versus max
speed Network size 20
42
Numerical results (contd)
average of interruptions per connection versus
max speed Network size 20
43
Numerical results (contd)
Probability of termination versus max
speed Network size 20
44
Numerical results (contd)
Total number of connections supported versus
network size Max speed 20 m/s
45
Numerical results (contd)
Average of interruptions per connection versus
network size Max speed 20 m/s
46
Numerical results (contd)
Probability of termination versus network
size Max speed 20 m/s
47
Conclusions

• Reliable QoS routing in ad hoc networks proposed
• Receiver initiated bandwidth reservation
• Sequential maltipath setup
• Bandwidth reservation minimize the impact to
  further reservation
• Not maximum bandwidth calculation
• Sequential multipath setup
• Avoid collision
• Longer path setup

48
Thank You