Bandwidth Allocation For Contingency Cellular Network

1

• ????????????????
• Bandwidth Allocation For Contingency
  Cellular Network

????????? ??????
2
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

3
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

4
Introduction

• ??????,??????????,???????
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5
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6
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8
??????????????

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• ???BSC/RNC?????(MSC)
• ????????
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• 921??
• ??????15?,????????
• 88??
• ????????3302?
• ??????????1800?
• 550?????????????

???? ??????????????
9
Golden 72 Hours

• ????,??72??????
• The survival rate is 90 within 24 hours
• 50 between 24 and 48 hours
• 20 between 48 and 72 hours.
• The chances of survival over 72 hours are quite
  rare.

???? http//baike.baidu.com
10
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11
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12
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

13
?????????????????

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• ??????????????????????????????????????????????????
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14
?????????????

• ?????(Walkie-Talkie)
• ???????????,??????
• ??????,???????????
• ?????????????????????????????????
• ??
• ??????,?????
• ???????????
• ????????????
• ??
• ??????????? (e.g. ??)
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15
?????????????

• ?????(Amateur radio)
• ????(Ham radio),????????,????????
• ??
• ???????????????????????????,?????????
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• ??
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• ?????,????????,???????????
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16
???????? ??????

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• ???????????????????,?????(MEO Medium-Earth
  Orbit)??500015000km,?????????(Odyssey)?????(LEO
  Low-Earth Orbit)??5001500km???,?Motorola???(Irid
  ium)
• ??
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17
???????? ??????

• ??????(Trunking radio)
• ?????????,?Project 25?TETRA
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18
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19
??????????MANET

• MANET(Mobile Adhoc Network )
• Ad hoc????????????????????,?????????????????????,?
  ???????,????????????
• P2Pnet
• ?????????????????????????????Multi-hop Ad-Hoc
  Network??????? MANET,?????Internet????????????VoIP
  ????????????
• ??
• ?????????????????????????,??????
• ???????????,????,????,?????????
• ??
• ????????????????,???????????
• ??????VoIP???????,????
• ??????,??????,???????????

20
????????
???? ??? ?? ??????? ??????? ????????? ??????? ???? ?????
Walkie- Talkie ? ???? ? ????? ????? ? ? ?
Amateur Radio ? ??????? ? ? ????? ? ? ?
?????? ?? ?? ? ? ? ? ? ?
?????? ? (??) ?? ?(?????) ? ????? ? ? ?
?????? ? (??) ?? ?(?????) ? ? ? ? ?
MANET ? ??????? ???? ? ? ? ? ?
21
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

22
CCN Introduction

• ???????????, CCN
• ????????????
• ????????????
• ????????????
• ????
• ????????????

23
CCN?????

• ??2G?3G??????
• ????????
• ??????????
• ???????
• Reuse?????
• ??????????
• ????????,?????
• ??????topology,?????
• ?????????????????
• ????
• ???????line-of-sight??
• ?????
• ?????????????
• ?????
• ?????????
• ????(?????)????,??????

24
CCN????

• Connected station(???)
• Isolated station(???)
• Contingency Recover Package(?????)
• Power module
• Inter-Cell Communications Module (ICC Module)
• Emulated Controller Module (EC Module)
• Satellite Communications Module (optional)

???
???
??????
???
(ICC Module)
???
25
CCN????
ICC Module
ICC Module
26
CCN???????

• ???????? (Damage Assessment Phase)
• ??????????? (CCN Planning Phase)
• ??????????????????
• ??????????? (CCN Deployment Phase)
• ??????????? (CCN Operation Phase)
• ??????

27
CCN????
???? ?? ?/??? ?/??? ?/??? ?? ??
S Signaling Traffic Base Station ? Radio Core Network ????control message??call setup ????control message??call setup
1 ???? ???? ? ??(?)?? ?????? ?????? ?????????? ??????????
2 ???? ???? ???? ?????? ? ? ? ?????? ?????? ?????? ???????????? ????????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? ???????????????????????????? ????????????????????????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? A ?????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? B ?????????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? C ???????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? D ????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? E ????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? F ????????????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? G ?????????????
3 ???? ?????? ?????? ?????? ??(?)?? ? ? ? ? ?????? ?????? ????/???? ?????? H ?????????
4 ???? ????/???? ????/???? ?????? ?????? ? ? ? ? ???? ????? ?????? ???????? ?????????????????????? ??????????????????????
28
CCN???????
CCN channel?? CCN channel??
??? ???????
???? ????
?? ????

• ???????????
• ????????????
• ?????????????
• ????????????
• ??????,?????
• ????????QoS

CCN ????channel?? CCN ????channel??
??????? ??????(Bandwidth/channel)
???? e.g.64K
???? e.g.16K
29
CCN????

• ????(Ordinary Mode)
• CCN????????CCN?????????
• ??????
• ???????????
• ???????(Walkie-Talkie Mode)
• CCN??????????????????
• CCN??????????
• ????????????????????
• ????????????????????
• ?????
• ?119?? (CCN-119)
• ??????????,?118
• ???????????????????

30
CCN????

• ??????(Priority Group Mode)
• ???????????
• ????????,??????????????
• ????????????,??????
• ??????,?????
• ????
• ?????,???????,?????
• ?????????????????
• ???,???????????????
• ???????????????
• ????
• CCN????????
• ????????,??12???1??????????
• ????

31
????????
???? ??? ?? ??????? ??????? ????????? ??????? ???? ?????
Walkie- Talkie ? ???? ? ????? ????? ? ? ?
Amateur Radio ? ??????? ? ? ????? ? ? ?
?????? ?? ?? ? ? ? ? ? ?
?????? ? (??) ?? ?(?????) ? ????? ? ? ?
?????? ? (??) ?? ?(?????) ? ? ? ? ?
MANET ? ??????? ???? ? ? ? ? ?
CCN ?????? ? ? ??? ??? ? ? ? ? ?
32
?? CCN ????????

• ????????
• ????????????????,?????????????????????????????????
  ??????
• ????
• ????????,????????,????????
• ????
• CCN???????????????,???????,??????????????????????,
  ??????,??????????,????????
• Intranet??
• ?????????????????????????,Intranet????????????????
  ????????????,????????????
• ???????
• ???????????????,????????,??????????

33
?? CCN ????????

• ??????
• ?????priority based admission control policy
• ?????
• ?????EC module???,??????????,??forwarding
  tree,????CCN??,??????,??????????
• ???CCN
• ??????????,???CCN???????

34
CCN?????????

• ?????????????????,??????
• ??????,??????
• ????????????,??????????

35
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

36
Bandwidth Allocation for CCN

• ????????????CCN????
• ???????
• Bandwidth allocation?????
• ??????
• ???QoS???????????
• ???????

37
Bandwidth Allocation for CCN????

• Bandwidth Allocation??
• ??????
• ????????????
• Circuit Switching
• ???????
• ?????QoS
• ?????
• ??Bandwidth Allocation?Channel Allocation??
• Topology????????,???,Reallocate

38
Bandwidth Allocation for CCNProblem Definition

• ????
• ????????,??
• ???????
• ???????
• ????(???, ??, ??)
• ????(???????????)
• ????
• ???
• ????
• ????????
• ??????

39
Bandwidth Allocation for CCNProblem Definition

• ????
• ??????
• ???????
• ???????
• Aggregate traffic????upstream link capacity
• Local traffic
• Forwarding traffic
• ??????????
• ?????????,?????local traffic?????channel?
• ??channel??????
• ????????

40
Model of Bandwidth Allocation for CCNCCN
forwarding tree

• Given CCN forwarding tree T(V,E), where
• , v1 is the
  root of T
• Cci i1,2,3,,n is the set of uplink
  capacity of vi
• ci the uplink capacity of vi
• ci cj , if vj is the parent node of vi

41
Model of Bandwidth Allocation for CCNCCN
channel class

• Bbj j1,2,3,,m is the set of bandwidth
  required per channel class
• bj the bandwidth required of channel class j

Channel class Bandwidth/Channel (bj)
1 e.g.64K
2 e.g.32K
3 e.g.16K
m e.g. ?K
42
Model of Bandwidth Allocation for CCNCCN profit
function for bandwidth allocation

• 
  is the set of the profit of channel assigned
• fij the profit of the first channel of class j
  assigned to vi
• g(k) the profit attenuation function of the
  k-th same channel class assigned to the same
  node, for example, g(k) ,

43
Model of Bandwidth Allocation for CCNCCN
channel assigned for basic needs

• is the
  set of the amount of basic channel needs
• dij the basic needs of channel class j
  assigned to vi

44
Model of Bandwidth Allocation for CCNCCN
channel assigned

• is the
  set of the amount of channel assigned
• aij the amount of channel class j assigned to
  vi

45
Model of Bandwidth Allocation for CCNObjective
function

• Our problem is to find aij A,
• such that
• is maximized
• subject to
• and
  
  
• is local
  bandwidth required of vi

46
Problem ComplexityKnapsack Problem

• 0-1 Knapsack Problem?N????????,??
• ??????W (w1, w2, , wn) ???P (p1, p2, , pn)
• ????????????C
• ???????????
• 0-1 Knapsack Problem is NP-Hard
• Richard M. Karp (1972). "Reducibility Among
  Combinatorial Problems. In R. E. Miller and J.
  W. Thatcher (editors). Complexity of Computer
  Computations. New York Plenum. pp. 85103.
• Garey, M. D. Johnson. Computers and
  Intractability A Guide to the Theory of
  NP-Completeness. 1979. ISBN 0-7167-1045-5.

47
Problem ComplexityBandwidth Allocation for CCN

• Bandwidth Allocation for CCN (CCN-BA)
• ???????(vi),?m?channel class?????,???uplink????,??
  
• ??Channel class???????? (b1, b2, , bm)??? (fi1,
  fi2, , fim)
• ??uplink????????(ci)
• ????channel???????
• Nested 0-1 Knapsack Problem
• CCN forwarding tree

BW of Channel class (b1, b2, , bm)
???(vi) ?? (fi1, fi2, , fim)
48
Problem Complexity Reduce CCN-BA to Knapsack
Problem

• ??????????

CCN-BA
0-1 Knapsack Problem

• T(V,E)
• V v1, E Ø
• C C
• B W
• F P
• D 0
• G 1

• C
• W
• P

49
Problem ComplexityNP-Hard

• Given an instance XC,W,P in 0-1 knapsack
  problem, we can find an instance
  YV,T,C,B,F,D,G in CCN-BA such that an optimal
  solution ay for Y is also an optimal solution for
  X. Let instance Y be a one level tree, where
  VTv1, CC, BW, FP, D0, and G1.
  Denote the total profit of a solution a for X and
  Y to be px(a) and py(a), respectively. Because
  FP, we can easily prove px(a) and py(a) are
  equal. For simplicity, both px(a) and py(a) are
  denoted as p (a).
• First, we prove ay is a valid allocation for X.
  Since BW, FP, and CC, any solution of Y
  whose total bandwidth must less than or equal to
  the given limit C so that ay must be a valid
  allocation for X.
• Since instance Y is a one level tree, for a
  similar argument, we can prove that any valid
  allocation ax for X is also a valid allocation
  for Y.

50
Problem ComplexityNP-Hard

• Next, we prove that an optimal solution ay for Y
  is also an optimal solution for X by
  contradiction. As we have proved, ay is also a
  valid allocation for X, whose total profit is
  p(ay). Assume ay is not an optimal allocation for
  X, there must be another allocation ax, whose
  total profit p(ax) is greater than p(ay). And any
  valid ax is also a valid allocation for Y, whose
  total profit is p(ax), which is greater than
  p(ay). This contradicts to the assumption that ay
  is an optimal solution for Y. As a result, ay
  must be an optimal solution for X. The reduction
  of CCN-BA to 0-1 Knapsack Problem is done. The
  proof of NP-hardness of CCN-BA is
  straightforward. Q.E.D.
• Bandwidth Allocation for CCN is a nested 0-1
  knapsack problem and NP-Hard

51
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

52
Heuristic Algorithm Design

• Bandwidth Allocation Greedy approach (BAG) Flow
  Diagram

profit densityF/bj
53
Heuristic Algorithm Design

• BAG algorithm pseudo code
• Greedy approach
• CCN-BA(T,C,B,F,D)
• Set A / the amount of channel class j
  assigned to vi/
• Set V /???channel?candidate node/
• initial A D
• initial V VT
• initial C C-(A B)
• if any ci lt minimum bj
• delete vi descent(vi) from V
• end if

54
Heuristic Algorithm Design

• BAG algorithm pseudo code
• Greedy approach (cont.)
• while V is not empty do
• sort F of V by profit density
• let fij g(k) be a highest profit density
  assign of F subject to min_ci(from
• vi to v1) bj
• plus 1 to aij
• minus bj from each ci(from vi to v1)
• update fij g(k1) to F
• if any ci lt minimum bj
• delete vi descent(vi) from V
• end if
• end while

55
CCN-BA BAG example

• Given

CCN forwarding tree
Bandwidth requirement of channel class
Channel class Bandwidth/channel (bj)
1 12K
2 7K
3 5K
Attenuation Function g(k)
Initial profit (fij)
Basic needs (dij)
channel class vi 12k 7k 5k
v1 16 13 5
v2 15 10 7
v3 25 20 10
v4 18 12 8
v5 29 23 15
channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 0 1 0
v4 0 1 0
v5 0 1 0
56
CCN-BA BAG example

• Initial

channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 0 1 0
v4 0 1 0
v5 0 1 0
Allocation (aij)
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 25 2.08 14.14 2.02 10 2.00
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 15 3.00
57
CCN-BA BAG example

• Allocate v5, 5k

channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 0 1 0
v4 0 1 0
v5 0 1 1
Allocation (aij)
12k 7k 5k
v5 0 1 1
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 25 2.08 14.14 2.02 10 2.00
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 15 3.00
58
CCN-BA BAG example

• Remove v2,v4,v5 from candidate node

BSC/RNC
channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 0 1 0
v4 0 1 0
v5 0 1 1
Allocation (aij)
c118
v1
c24
c323
v2
v3
c413
c58
v4
v5
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 25 2.08 14.14 2.02 10 2.00
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 10.61 2.12
59
CCN-BA BAG example

• Allocate v3, 12k

channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 1 1 0
v4 0 1 0
v5 0 1 1
Allocation (aij)
12k 7k 5k
v3 1 1 0
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 25 2.08 14.14 2.02 10 2.00
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 10.61 2.12
60
CCN-BA BAG example

• Allocate v3, 5k

channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 1 1 1
v4 0 1 0
v5 0 1 1
Allocation (aij)
12k 7k 5k
v3 1 1 1
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 17.68 1.47 14.14 2.02 10 2.00
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 10.61 2.12
61
CCN-BA BAG example

• Remove v1,v3 from candidate node

channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 1 1 1
v4 0 1 0
v5 0 1 1
Allocation (aij)
Profit of channel assigned
Channel Class Node 12k 12k 7k 7k 5k 5k
Channel Class Node profit Profit density profit Profit density profit Profit density
v1 16 1.33 9.19 1.31 5 1.00
v2 15 1.25 7.07 1.01 7 1.40
v3 17.68 1.47 14.14 2.02 7.07 1.41
v4 18 1.50 8.49 1.21 8 1.60
v5 29 2.42 16.26 2.32 10.61 2.12
62
CCN-BA BAG example

• No more candidate node ? Finished

Allocation (aij)
channel class vi 12k 7k 5k
v1 0 1 0
v2 0 1 0
v3 1 1 1
v4 0 1 0
v5 0 1 1
Total profit basic needs profit channel
assigned by profit density (1310201223
)152510 128
63
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

64
????

• ??????BAG??????
• ??????????????,????BAG??????????????
• ???
• ??????
• ???
• ??????
• ???
• ? ????
• ???????6?7?8?9?10?100
• ???10?????

65
BAG?????????
66
????

• ????????????,??????????,???????????(Normalization)
  ????(Deviations from optimum solution,??Deviation
  )
• 610????
• ?? (???-????) / (???-???)
• ???????????????Total Profit
• ???????????????Total Profit
• ????BAG?????Total Profit
• 100????
• ??? (????-????) / ( max(????,????) -????)
• ????10??????????Total Profit
• ????10??????????Total Profit
• ????BAG?????Total Profit

67
???????

• Link Capacity(ci)32100
• Initial Profit(fij)30100
• Attenuation Function(g(k)) ?
• Channel Class(bj)1632
• Forwarding Tree Size6?7?8?9?10?100
• ??????
• ???Intel(R) Core(TM)2 Duo CPU E7400 _at_ 2.80GHz ??
• ???2.00 GB
• ????32??Microsoft Windows XP SP3

?
68
????

• ???
• 50?????
• ????(Deviation)??010.68
• ???28?
• ?????????
• ?????2.50???4.46
• ?????98.21???96.71

69
????
6 nodes
7 nodes
8 nodes
9 nodes
10 nodes
70
????

• ???
• 50?????
• ????(Deviation)??014.03
• ???19?
• ?????????
• ????2.164.76
• ?????97.58???96.32

71
????
6 nodes
7 nodes
8 nodes
9 nodes
10 nodes
72
????

• ???
• 10?????
• BAG???????????
• ????????21.12 41.30,?????32.71

73
????
Amount of base station Experiment 1 Experiment 2 Average Deviation
6 2.50 3.14 2.82
7 2.58 3.87 3.22
8 2.95 2.16 2.55
9 3.55 4.18 3.87
10 4.46 4.76 4.61
Average Deviation 3.21 3.62 3.41

• BAG???????
• ???,????????3.21
• ???,????????3.62
• ??????????
• BAG??????????????,?????6?????2.82???10?????4.61
• ?????(???)?????,?8?????,????????12?????,?10?????,?
  ???7????
• BAG??????,?????????,????????????,????????

Amount of base station Experiment 1 Experiment 2 Total Number of Optimum Solution
6 6 3 9
7 7 4 11
8 6 6 12
9 5 3 8
10 4 3 7
Total Number of Optimum Solution 28 19 47
74
Outline

• Introduction
• Communication systems crash by natural disasters
• Requirements analysis of contingency
  communication system
• Related work
• Common contingency communication systems
• Contingency Cellular Network (CCN)
• Bandwidth allocation for CCN
• Concept
• Problem definition
• Model
• Algorithm design
• Evaluation
• Summary future work

75
Summary

• ?????????????????,?????????????????????????????,??
  ????????????,?????????????(Contingency Cellular
  Network,CCN)
• ????????????,?CCN???????????,???????????????,?????
  ??,??????
• ???????????,CCN?????????,????????????????
• ??????????????????????????,????CCN??????????????,?
  ??????????,????(??????)??????CCN??????
• ??????????,???????????????????????

76
Future Work

• CCN???????????
• ??????,????????????
• ?????????????????????
• ????????????
• Priority-based????

77
Q A
77