a load aware hybrid channel assignment for multi-radio wireless mesh network
TRANSCRIPT
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
1/16
A Load Aware Hybrid Channel
Assignment for Multi-Radio
Wireless Mesh Network
Tran Minh Trung
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
2/16
Multi-channel, Multi radio
Mesh router Mesh router:Multiple interfaces
Each interface can workon multiple channels
Challenges
How to assign channel for each interface?How to decide when to transmit packets
and which interface will be used?
Mesh
router
IF1
IF2
Mesh
router
IF1
IF2
Mesh
router
IF1
IF2
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
3/16
Channel assignment
Dynamic
StaticHybrid
Scheduling algorithm
CSMA/CD
TDMA
Existing approaches
Can utilize the
advantage of both
dynamic and static
mechanisms
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
4/16
Hybrid mechanism
Hybrid mechanism
Some interfaces fixed on a channel
Different nodes use different fixed channels
Other interfaces switch as needed Dynamic assignment
Mesh
router
IF1
IF2
Mesh
router
IF2
IF2
Mesh
router
IF2
IF2
c1
c2
c3
c4
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
5/16
Fixed interface contention problem
4
6
5
8
1
2
3
2
7
9
C(6)=1
C(7)=1
C(4)=1
9 links contending on a single channel
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
6/16
Net-X:
Equalize the # of fixed interfaces on each channel
Problem: Each node have different traffic load and
contention degree
Proposed solution:
Load aware channel assignment
Solution approaches
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
7/16
Load aware channel assignment
4
6
5
8
1
2
3
2
7
9
C(4) = 2
C(6) = 1
C(7) = 1
C(5) = ?
Channel ID # Fixed
Interface
Contention
Deg.
1 2 2
2 1 4
Net-X: FC(5)= 2
Proposed solution: FC(5)=1
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
8/16
Channel selection procedures
Step 1: Initializing
Nodes choose the same common channel
Broadcast hello message including channel status table
Step 2: Selecting channel Select channel basing on contention degree information
If contention degrees are equal -> select channel basing on thenumber of fixed interface on each channel
Step 3: Finalizing
Update channel status basing on new selected channel
Broadcast new channel status on common channel
Switch channel from common channel to selected channel
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
9/16
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
10/16
Simulation parameters (2)
param.topo maxx: 1000(m)
maxy: 1000(m)
nnodes: 36
type: [1:random 2:manual]
param.mac Slotted base
framesize: 10 (~20ms) slotsize: 1 (~2ms)
allocatetype: [1 2 3] 1: Hop based
2: Load based 3: Hybrid
param.phy txrange: 250 (m)
nchannel: 1-5
linkrate: 2 Mbps
swtime: 0.0500 (~0.1ms)
Pktsize = 512bytes
param.conn method: [1 2]
1: Random
type: [1 2]
1: CBR
param.route Type: [1] 1: Min-hops
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
11/16
Simulation result
The throughput of three different channel
assignment algorithms
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
12/16
Conclusions
Utilize both advantage of dynamic and static
mechanisms
Avoids co-ordination issues, deafness problems
Retain flexibility of dynamic assignment
Easy for implementation (more realistic)
Modify existing 802.11 protocol
Can be implemented in user space daemon
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
13/16
References
1. Akyildiz, I.F., Wang, X. and Wang, W., ``Wireless Mesh Networks: A Survey,'' Computer
Networks Journal (Elsevier), March 2005
2. Pradeep Kyasanur and Nitin H. Vaidya, Routing and Interface Assignment in Multi-Channel
Multi-Interface Wireless Networks, in WCNC, 2005.
3. Richard Draves, Jitendra Padhye, and Brian Zill, Routing in Multi-Radio, Multi-Hop Wireless
Mesh Networks, in ACM Mobicom, 2004.4. Ashish Raniwala, Kartik Gopalan, and Tzi-cker Chiueh, Centralized Channel Assignment and
Routing Algorithms for Multi-Channel Wireless Mesh Networks, Mobile Computing and
Communications Review, vol. 8, no. 2, pp. 5065, April 2004.
5. Jungmin So and Nitin H. Vaidya, Multi-channel MAC for Ad Hoc Networks: Handling Multi-
Channel Hidden Terminals using a Single Transceiver, in Mobihoc, 2004.
6. P. Bahl, R. Chandra, and J. Dunagan, SSCH: Slotted Seeded Channel Hopping for CapacityImprovement in IEEE 802.11 Ad-Hoc Wireless Networks, in ACM Mobicom, 2004.
7. Shih-Lin Wu, Chih-Yu Lin, Yu-Chee Tseng, and Jang-Ping Sheu, A New Multi-Channe MAC
Protocol with On-Demand Channel Assignment for Multi-Hop Mobile Ad Hoc Net works, in
International Symposium on Parallel Architectures, Algorithms and Network (ISPAN), 2000
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
14/16
Appendix
Implementation
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
15/16
Implementation architecture
-
8/8/2019 A Load Aware Hybrid Channel Assignment for Multi-Radio Wireless Mesh Network
16/16
Channel selection procedure