Kontextbewutes und interaktives Routing

1
Kontextbewußtes und interaktives Routing

• Sven Hanemann, Matthew Smith and Bernd Freisleben
• Department of Mathematics and Computer Science
• University of Marburg, Germany
• hanemann/matthew/freisleb_at_
• informatik.uni-marburg.de

2
Overview

• Introduction
• Cross-Layer Design
• Our Approach
• Results
• Future Work

3
Introduction

• Current Trend X-Aware Routing in ad hoc
  networks
• Energy-aware routing
• Bandwidth-aware routing
• Mobility-aware routing
• Location/position-aware routing
• Topology/Neighborhood-aware routing
• Fault/Robustness-aware routing
• Load/Communication-aware routing
• Security-aware routing
• Scalability-aware routing
• Device-aware routing
• Application/QoS-aware routing

Multi Level
4
Cross-Layer Design (1)
5
Cross-Layer Design (2)

• Substantial gains in throughput,
• efficiency, and QoS can be achieved
• by exchanging information like
• Topology information
• Known energy constraints
• Application requirements

Optimization options offered by using topology
information
6
Cross-Layer Design (3)

• Optimization benefits of cross-layer design

7
Our Approach A Context-Aware and Interactive
Routing Framework (1)
Application Real-/non real time services
Transport TCP/UDP/RTP
Network IP/IntSErv/Diffserv
Link Link quality,FEC/ARQ
Physical Channel conditions

• Current Aims
• Investigate cross-layer interactions between
  application layer and routing
• Investigate cross-layer interactions between link
  layer and routing

8
Our Approach A Context-Aware and Interactive
Routing Framework (2)

• Methods
• Simulations using our own simulator
• However, simulations are not flexible enough to
  identify the repercussions of cross-layer
  adaptations with real applications
• Design of an emulation environment

Enhanced emulation system
Virtual UML network
9
Our Approach A Context-Aware and Interactive
Routing Framework (3)

• Emulation of ad hoc nodes by using an adapted
  user mode Linux system (UML)

Virtual ad hoc network
Virtual node kernel
10
Our Approach A Context-Aware and Interactive
Routing Framework (3)

• Modification and enhancement of an existing
  emulator (MobiEmu) for testing cross- layer
  adaptations with existing applications

Statistical Evaluation Information
11
Results 2003

• An Emulation Environment for Studying
  Cross-Layer Design

Adaptation
Application Layer

• Proactive Distance-Vector Multipath Routing for
• Wireless Ad Hoc Networks
• (Proceedings of IASTED International
  Conference
• Communication Systems and Networks (CSN
  2003),
• Result Load distribution, Reduced Link
  average link break
• time

Adaptation
Transport Layer

• Update Message Delay An Approach for Improving
• Distance Vector Routing in Wireless Ad Hoc
• Networks
• (Proceedings of IEEE Symposium on
  Communications and
• Vehicular Technology (SCVT 2003),
• Result Routing message reduction up to 15

Adaptation
Network Layer
Adaptation
Mac/Link Layer

• Reducing Packet Transmission in Ad Hoc Routing
• Protocols by Adaptive Neighbor Discovery
• (Proceedings of the International Conference
  on
• Wireless Networks 2003 (ICWN03)
• Result Constant mean error rate by dynamic
  adaptation

Adaptation
Physical Layer
12
Proactive Distance-Vector Multipath Routing for
Wireless Ad Hoc Networks

• Aim
• Equip proactive routing with the capability of
  using multiple paths to each target by using
  already available topology information
• Benefits
• Load distribution, bottleneck avoidance, fairness
  and
• less communication breaks

Ohne Mehrwege
Mit Mehrwege
TERA mit Mehrwege TERA ohne Mehrwege
Last in
Last in
Communication breakdown length sec
Gitterhöhe
Gitterhöhe
Gitterbreite
Gitterbreite
Movement speed in m/s
Without multipath
With multipath
Improved average link breakage duration
13
Update Message Delay An Approach for Improving
Distance Vector Routing in Wireless Ad Hoc
Networks

• Aim
• Improving bandwidth and energy consumption by
  reducing
• unnecessary updates
• Benefits
• Routing message reduction up to 15

Number of required messages (180 meters
transmission range)
Reachable destinations (180 meters
transmission range)
14
Reducing Packet Transmission in Ad Hoc Routing
Protocols by Adaptive Neighbor Discovery (1)

• Aim
• Minimize bandwidth consumption according to user
  requirements by adjusting neighbor detection
  accuracy
• Benefits
• Constant average error
• rate by dynamic adaptation
• Adaptive neighbor detection
• algoritm
• Maximal service availability with
• minimal bandwidth consumption

Scheme of a single node
15
Reducing Packet Transmission in Ad Hoc Routing
Protocols by Adaptive Neighbor Discovery (2)

• Constant average error rate by dynamic
  adaptation

Bandwidth consumption with constant average error
rate
Evaluation of algorithm behavior
16
Future Work

• Enhancement of the emulation environment for
  improved evaluation
• Further optimization through cross-layer
  functionality
• Adaptive routing based on current link, network
  and traffic conditions
• Integration of MAC/Link layer adaptations (multi
  class queuing, prioritization, interference
  conditions)
• Throughput / delay / load / energy tradeoffs
• What information should be passed between layers
  and how should they interact?
• Do reconfigurable, application-tailored protocol
  stacks (at runtime) make sense?
• Should layering be considered harmful? ? Protocol
  heap idea?