1

Using Network Coding for Dependent Data Broadcasting

in a Mobile Environment

Chung-Hua Chu De-Nian Yang and

Ming-Syan Chen

IEEE GLOBECOM 2007

Reporter Lzu Lin Wang

2

Outline

INTRODUCTION PROBLEM FORMULATION GENERATING A BROADCAST PROGRAM EXPERIMENTAL RESULTS CONCLUSION

3

INTRODUCTION-Network coding

Network Coding Instead of simply forwarding data intermediate

node encodes several input packets into one output packet

INTRODUCTION-Network coding

Linear network coding The number of retrieved packets has to at least larger than the

number of original packets otherwise there are several linearly dependent equations

Random network coding The probability of selecting the linearly dependent combinations

of the data items can be ignored even in small field sizes

The traditional network coding does not leverage the data items stored in mobile users to encode all data items and thereby the unnecessary encoding of data items leads to more access delay

4

5

INTRODUCTION

DOP (Demand-Oriented Encoding Problem) The problem is to minimize the average access

time with maximizing the number of the demanding users

Determine the optimal linear combination of the data item in the multiple channels environment

Demand-Oriented Pairing (DOP) algorithm selects the data items such that the linear combination of the selected items can satisfy the maximal number of the mobile users

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

2

Outline

INTRODUCTION PROBLEM FORMULATION GENERATING A BROADCAST PROGRAM EXPERIMENTAL RESULTS CONCLUSION

3

INTRODUCTION-Network coding

Network Coding Instead of simply forwarding data intermediate

node encodes several input packets into one output packet

INTRODUCTION-Network coding

Linear network coding The number of retrieved packets has to at least larger than the

number of original packets otherwise there are several linearly dependent equations

Random network coding The probability of selecting the linearly dependent combinations

of the data items can be ignored even in small field sizes

The traditional network coding does not leverage the data items stored in mobile users to encode all data items and thereby the unnecessary encoding of data items leads to more access delay

4

5

INTRODUCTION

DOP (Demand-Oriented Encoding Problem) The problem is to minimize the average access

time with maximizing the number of the demanding users

Determine the optimal linear combination of the data item in the multiple channels environment

Demand-Oriented Pairing (DOP) algorithm selects the data items such that the linear combination of the selected items can satisfy the maximal number of the mobile users

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

3

INTRODUCTION-Network coding

Network Coding Instead of simply forwarding data intermediate

node encodes several input packets into one output packet

INTRODUCTION-Network coding

Linear network coding The number of retrieved packets has to at least larger than the

number of original packets otherwise there are several linearly dependent equations

Random network coding The probability of selecting the linearly dependent combinations

of the data items can be ignored even in small field sizes

The traditional network coding does not leverage the data items stored in mobile users to encode all data items and thereby the unnecessary encoding of data items leads to more access delay

4

5

INTRODUCTION

DOP (Demand-Oriented Encoding Problem) The problem is to minimize the average access

time with maximizing the number of the demanding users

Determine the optimal linear combination of the data item in the multiple channels environment

Demand-Oriented Pairing (DOP) algorithm selects the data items such that the linear combination of the selected items can satisfy the maximal number of the mobile users

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

INTRODUCTION-Network coding

Linear network coding The number of retrieved packets has to at least larger than the

number of original packets otherwise there are several linearly dependent equations

Random network coding The probability of selecting the linearly dependent combinations

of the data items can be ignored even in small field sizes

The traditional network coding does not leverage the data items stored in mobile users to encode all data items and thereby the unnecessary encoding of data items leads to more access delay

4

5

INTRODUCTION

DOP (Demand-Oriented Encoding Problem) The problem is to minimize the average access

time with maximizing the number of the demanding users

Determine the optimal linear combination of the data item in the multiple channels environment

Demand-Oriented Pairing (DOP) algorithm selects the data items such that the linear combination of the selected items can satisfy the maximal number of the mobile users

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

5

INTRODUCTION

DOP (Demand-Oriented Encoding Problem) The problem is to minimize the average access

time with maximizing the number of the demanding users

Determine the optimal linear combination of the data item in the multiple channels environment

Demand-Oriented Pairing (DOP) algorithm selects the data items such that the linear combination of the selected items can satisfy the maximal number of the mobile users

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

6

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

7

PROBLEM FORMULATION-Notation and Definition

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

8

PROBLEM FORMULATION-Notation and Definition

The problem is to minimize the average access time with the maximizing

where represents the number of user members in 1048647

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

9

PROBLEM FORMULATION-Derivation of Access Time

Average access time

The number of complete broadcast cycles for a mobile user ui to retrieve the encoded data

The length ofbroadcast cycle

The number of remaining timeslots that the interested user needs to download after waitingfor cycle i cycles

z data sizeb Bandwidth of broadcast channel

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

10

PROBLEM FORMULATION-Derivation of Access Time

The number of channel =2 User i stored data is BK Query data items is AD L is equal to 3 ( ) is equal 1 ATT is equal to

In the same time slot

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

11

PROBLEM FORMULATION-Derivation of Access Time

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

GENERATING A BROADCAST PROGRAM

- Demand-Oriented Pairing (DOP) algorithm

1 DOP creates Table DT (Demanding Table)

2 DOP creates Demanding Graph

3 DOP will delete the user members in Table DT if the encoding data can be decoded correctly by the data items stored in users

4 Add the user members to Table DT whose query data items correspond to new stored data items

12

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

GENERATING A BROADCAST PROGRAM- DOP creates Table DT (Demanding Table)

13

Encoding Data Demanding members

Encoding Data Demanding members

21 dd 31 dd 41 dd 51 dd 61 dd 32 dd 42 dd 52 dd

62 dd 43 dd 53 dd 63 dd 54 dd 64 dd 65 dd

2u

1u 2u

1u

4u3u

3u

1u1u 2u3u3u2u

6u 7u6u 7u

8u 10u9u 10u 11u

5u

8u4u 9u11u8u 9u7u5u7u 9u4u

8u 11u4u 5u

0

0

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

GENERATING A BROADCAST PROGRAM- Demanding Graph

14

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

GENERATING A BROADCAST PROGRAM- Matching

15

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

GENERATING A BROADCAST PROGRAM

- Matching

16

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

1d 2d 3d 4d 5d 6d

14 3

2 4 2

5

3

3 43

23

31

1 16

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

17

GENERATING A BROADCAST PROGRAM- Algorithm DOP

E1

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

18

EXPERIMENTAL RESULTS

Simulation Model

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

19

EXPERIMENTAL RESULTS

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay

20

CONCLUSION

Author proposed a novel data broadcasting framework that adopts network coding with leveraging the data items stored in users to reduce the average access time

The algorithm selects the data items to be encoded according to the data items stored in users to satisfy maximal number of mobile users and reduce access delay