bandwidth balancing in multi- channel ieee 802.16 wireless mesh networks claudio cicconetti, ian f....
DESCRIPTION
Introduction_ (1) There are two coordination mode in WiMax mesh network Centralized Distributed In the distributed mode,SSs can communicate to their neighbors directlyTRANSCRIPT
Bandwidth Balancing in Multi-Channel IEEE 802.16 Wireless Mesh networks
Claudio Cicconetti, Ian F. AkyildizSchool of Electrical and Computer Engineering
Georgia Institute of Technology, Atlanta
Luciano LenziniDipartimento di Ingegneria dell’Informazione
University of Pisa
IEEE INFOCOM 2007
Outline
Introduction Fair end-to-end bandwidth allocation Performance Evaluation Conclusion
Introduction_802.16(1)
There are two coordination mode in WiMax mesh network Centralized Distributed
In the distributed mode ,SSs can communicate to their neighbors directly
Introduction_802.16(2)
The frame in mesh mode consists of a control subframe and a data subframe
Introduction_802.16(3)
The amount of bytes conveyed by a slot depends on the Modulation and Coding Scheme (MCS)
Every node dynamically adapts the MCS from neighbor to neighbor
Data transmission in MSH-DSCH is coordinated by the following procedure Requester asks a neighbor node, granter, to allocate some
bandwidth the granter advertises a set of slots as ‘granted’ to the
requester the requester confirms that it will actually use that set of
slots (or part thereof) to transmit data
Request<slot,frame,channel>Confirm
Introduction_802.16(4)
Fair end-to-end bandwidth allocation
There are some assumptions The network topology is fixed Each node has a single radio interface Each node can dynamically switch to
one channel at a time The “fairness” is a desirable
property for any MAC protocol
Fair end-to-end bandwidth allocation
Define 1 (traffic flow): A traffic flow is a stream of IP datagrams from a source to a destination node
Fair end-to-end bandwidth allocationNumber of
bytes that X has notified to YNumber of
bytes that X has confirmed to YNumber of bytes awaiting transmission at
X toward YNumber of bytes that Queue i could’t consume
Number of bytes that Y has
notified to XNumber of
bytes that X has granted to Y
The set of all active traffic flows served by this node
An indicator function which equals 1 if j is
under at queue i
The number of bytes that queue I could’t consume
granting queue is inactive, since X granted the byte requested by Y
Fair end-to-end bandwidth allocation
the requesting queue is inactive
The request demands can’t fulfilled by the granter
Fair end-to-end bandwidth allocation
The grant horizon ,at time t , in units of frame ,can be expressed as
Request
<slot,frame,channel>
t t+ t+
Fair end-to-end bandwidth allocation
Fair end-to-end bandwidth allocation
Simulation _Environment
Simulation is implement in the ns2 network simulator
Channel bandwidth is 10 MHZ Frame duration is 4 ms Nodes employ the 16-QAM-1/2 MCS Each traffic flow had a separate
100kB buffer
Simulation _(1)
A fair index n denotes the number of traffic flow Xi the throughput of the i-th traffic flow
Flow 1 2
Flow 2 2
Flow 3 2
(2+2+2)^2 / 3* (4+4+4) =36/36=1
EX:
Simulation _(2)
Simulation _(3)
Simulation _(4)
Simulation _(5)
Conclusion
Presented a distributed algorithm for bandwidth (FEBA) balancing in multi-channel IEEE 802.16 WMNs