M.Tech Project Stage One Presentation

1
M.Tech ProjectStage One Presentation

• Scheduling and Call Admission Control (CAC) in
  IEEE 802.16 Mesh Networks
• Presented by
• Jeevan B. Chalke (06329011)
• under the guidance of
• Prof. Anirudha Sahoo
• Department of Computer Science and Engineering
• Indian Institute of Technology

2
Outline

• Introduction
• Motivation
• Literature Survey
• Work Done
• Problem Definition
• Conclusion

3
Introduction

• IEEE 802.16 WiMax
• Greater coverage area
• Supports P2P, PMP and Mesh modes
• Mesh networks
• Importance
• Routing, Scheduling and Call Admission Control

4
Motivation

• WiMax mesh - a new technology
• Lot of literature available for PMP
• Currently, negligible mesh support (since
  optional)
• Not much work done in mesh
• Need efficient routing, scheduling and admission
  control mechanism

5
Literature Survey

• Overview of IEEE 802.16 Mesh Networks
• Scheduling in Mesh
• Routing Algorithms
• Scheduling Algorithms
• Call Admission Control

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Overview of 802.16 Mesh Networks

• Area divided in meshes and managed by MBS
• SS to SS transmission within mesh
• Mesh Frame
• 256 minislots
• Network control and Data subframes

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Scheduling in Mesh

• Distributed Scheduling
• One hop and two hop neighborhood
• Coordinated
• Transmit its own schedule on a PMP basis to all
  its neighbors
• Not rely on BS
• Collision free control messages
• Uncoordinated
• Direct request/grant mechanism
• Control message may collide

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Scheduling in Mesh (contd)

• Centralized Scheduling
• Transmission schedule is defined by mesh BS
• BS determines the flow assignments from the
  resource requests of the SS

Fig. 3 Mesh MSH-CSCH flow usage example (source
1)
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Routing Algorithms

• Should be scalable for larger networks
• Routing issues
• Link failure
• Interference
• DOS attacks
• Routing Algorithms
• Interference aware routing
• Blocking Metric, B(k)
• Routing for throughput maximization
• B(k), with traffic consideration
• Fixed routing for supporting QoS
• Resource reservation along fixed path

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Scheduling Algorithms

• Goals
• To achieve high system throughput
• To increase spatial reuse
• To provide fair access to SS
• Scheduling Algorithms
• Interference aware scheduling
• Concurrent transmission
• Centralized scheduling
• Provides per flow QoS guarantee to real-time and
  data applications
• Fair and efficient uplink scheduling
• Spatial reuse

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Call Admission Control

• Functions
• Accept or reject new flow as per the QoS
  requirement
• Maintaining database of accepted flow
• CAC for multihop wireless networks with QoS
• Admits subset of connections with QoS guarantee
• Admits all connections with degradation of QoS
  requirements

Delay D(si, ?i, Ki), for all i, z ... Delay
Constraint Where, D(si, ?i, Ki) is a function of
burst, rate and hope count for connection i, in
direction z Example Delay si / ?i Ki L /
?i, L size of packet
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Work Done

• Intel Pro/Wireless 5116 broadband interface
• Classification of functions to be implemented
• Designing CAC
• Dynamic services to provide QoS

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Bandwidth Stealing CAC

• Characteristics
• Equal bandwidth for all SS (fairness among SS)
• Each flow within SS can steal bandwidth to its
  maximum limit defined (fairness among flows)
• No bandwidth stealing from higher priority flow
• Simple and easy to implement
• Maintains accepted connections database for
  scheduler
• Limitations
• Predefined delay is assumed for given flow
• Need prior knowledge of number of SSs

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Dynamic Services

• Dynamic Services
• Addition (DSA)
• Change (DSC)
• Deletion (DSD)
• Message transfer between SS and BS
• Parsing and creating messages
• Data structure example

typedef struct sDsxRspData struct sDsxRspData
next char msgType UINT16 transactionId char
confirmationCode UINT16 cid tDsxRspData
Fig. 5 DSA message flow (source 1)
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Problem Definition

• Designing Efficient Scheduling and/or Call
  Admission Control in IEEE 802.16 Mesh Networks
• Which has
• Simple implementation (No complex routines and
  computations)
• Able to admit more number of connections per
  frame
• Provide QoS guarantees

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Timeline

• Plan
• Stage II
• Closely related routing, scheduling and admission
  control
• Designing scheduler and/or CAC
• Stage III
• If hardware available, implementing proposed
  algorithm on hardware
• Validating proposed algorithms

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Conclusion

• Designing algorithm for multihop network is
  always considered to be complex
• Routing is closely coupled with scheduling and
  call admission control
• It would be interesting to design and implement
  efficient algorithms which can admit more flows
  (with QoS guarantees) per frame

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References

• 1 IEEE. IEEE Standard for Local and
  metropolitan area networks Part 16 Air Interface
  for Fixed Broadband Wireless Access Systems,
  IEEE standard, October 2004.
• 2 H. Shetiya and V. Sharma, Algorithms for
  Routing and Centralized Scheduling to Provide QoS
  in IEEE 802.16 Mesh Networks, in WMuNeP 05
  Proceedings of the 1st ACM workshop on Wireless
  multimedia networking and performance modeling,
  New York, NY, USA, 2005, pp. 140-149, ACM Press.
• 3 Seungjoon Lee, Girija Narlikar, Martin Pal,
  Gordon Wilfong, Lisa Zhang., Admission Control
  for Multihop Wireless Backhaul Networks with QoS
  Support, IEEE WCNC 2006, Las Vegas NV, April
  2006
• 4 M. Cao, V. Raghunathan, and P. R. Kumar., A
  tractable algorithm for fair and efficient uplink
  scheduling of multi-hop wimax mesh networks, In
  Proceedings of 2nd IEEE Workshop on Wireless Mesh
  Networks (WiMesh 2006), September 2006.
• 5 H. Wei, S. Ganguly, A. Izmailov, and Z. Haas,
  Interference-Aware IEEE 802.16 WiMax Mesh
  Networks, in Vehicular Technology Conference,
  2005. VTC 2005-Spring. 2005 IEEE 61st, Vol. 5
  3102-3106.
• 6 F. Jin, A. Arora, J. Hwang, and H.-A. Choi,
  Routing and Packet Scheduling for Throughput
  Maximization in IEEE 802.16 Mesh Networks,
  submitted for publication.
• 7 J. Tao, F. Liu, Z. Zeng, and Z. Lin,
  Throughput Enhancement in WiMax Mesh Networks
  Using Concurrent Transmission, in International
  Conference on Wireless Communications, Networking
  and Mobile Computing, Sep 2005, pp. 871-874.
• 8 IEEE P802.16-REVd/D5-2004. Air Interface for
  Fixed Broadband Wireless Access Systems

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References (contd)

• 9 I. F. Akyildiz, X.Wang, andW.Wang, Wireless
  Mesh Network A Survey, January 2005.
• 10 Y. Yuan, H. Yang, S. Wong, S. Lu, W.
  Arbaugh, ROMER Resilient Opportunistic Mesh
  Routing for Wireless Mesh Networks, in
  Proceeding of IEEEWorkshop onWireless Mesh
  Networks (WiMesh), 2005.
• 11 R. Draves, J. Padhye, and B. Zill, Routing
  in Multi-radio, Multihop Wireless Mesh Networks,
  in ACM MobiCom, Philadelphia, PA, September 2004.
• 12 Chandra and A. Sahoo. An Efficient Call
  Admission Control for IEEE 802.16 Networks,
  Technical Report, Available http//www.it.iitb.ac
  .in/research/techreport/reports/30.pdf
• 13 Wang H., LiW. and Agrawal D.P. Dynamic
  admission control and QoS for 802.16 wireless
  MAN,Wireless Telecommunications Symposium, 2005,
  vol. no.pp. 60-66, 6-7 April 2005.
• 14 Intel Corporation. Intel Pro/Wireless 5116
  Broadband Interface, Available
  http//www.intel.com/network/connectivity/products
  /wireless/307327.pdf

20
Thank You
21
Backup Slides
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Model Assumptions

• Random routing proposed in IEEE 802.16 standard
• Fixed path from SS to MBS
• A node cannot send or receive simultaneously
• At any given time only one transmitter and
  receiver is active

• Link failure?

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Identification of Decisions yet to be made

• Problem turns out to be too difficult
• Scheduling and/or CAC
• Designing both will require little bit more time.
• Approach is that, first go for Scheduling and
  then CAC
• Problem turns out to be too easy
• Extension possible in these areas
• Routing algorithm instead of random routing
• Link failures
• Can mobility supports
• Variable routing paths