Routing Functional Components

1
Routing Functional Components

• Steven D. Jones (JHU/APL)
• Chunyue Liu (CCNY)
• Tarek Saadawi (CCNY)
• I-Jeng Wang (JHU/APL)

2
Motivation and Objectives

• Develop a component-oriented framework for design
  and analysis of routing protocols
• Most protocols can be constructed by common key
  components and many share fundamentally the same
  mechanisms/algorithms for specific components.
• Analysis and comparisons based on simulation of
  entire protocols provide inadequate
  characterization of performance.
• Component-oriented approach can provide insights
  into key aspects of protocols that lead to
  specific performance.
• New techniques can be developed for specific
  component to address the new challenges arise in
  applications
• Establish a framework for dynamic component
  configuration to support heterogeneous routing
• Component-wise reconfiguration provides more
  flexibility and can support the wider spectrum of
  operating conditions for tactical network

3
Routing Functional Components
Primary Functions
Supporting Functions
Packet Forwarding
Route Representation Determination
Dynamic Route Management
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Route Representation and Packet Forwarding

• Route Representation Determination
• Distributed information necessary to compute
  routes and the underlying algorithms
• Mechanisms
• Source routes
• Link state
• Routing table
• General next-hop utility
• Packet Forwarding
• Mechanism to forward data packet based on route
  information
• Largely driven by route representation
• More significant when multiple routes are
  available

5
Neighbor Discovery and Maintenance

• Dynamically maintain the knowledge of necessary
  neighborhood information
• Information from link layer
• Hello messages
• Information from information dissemination in
  support of routing
• Information from data transmission
• Might include information beyond the 1-hop
  neighbors for some protocols
• For example, multi-points relays for OLSR

6
Route Information Initialization

• Properly initialize route information under
  relevant constraints when a network is deployed
  or a new routing domain is configured
• Constraints can include time, overhead, energy,
  stealth
• Prior information useful and resources required
  to configure initialization is typically
  available when a tactical network is deployed
• Mechanisms
• Partial or complete
• Using route discovery driven by traffic models
  derived from IER

7
Dynamic Route Management Route Maintenance and
Failure Response

• Route Maintenance
• Properly update route information to address
  dynamics
• Mechanisms
• Triggering conditions
• Event-driven time-out, threshold on route
  quality, demand-driven
• Periodic
• Specific actions
• Route discovery
• Information dissemination
• Failure Response
• Respond to the detected loss of a link due to
  failure, mobility, or jamming
• Mechanisms
• Active properly update the route information to
  repair affected routes or compute alternative
  routes (TBRBF).
• Passive remove invalid route information due to
  the failure (AODV or DSR).
• Mixed

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Mapping Protocols to Functions
Route Representation Packet Forwarding Neighbor Discovery Maintenance Route Information Init. Route Maintenance Failure Response
AODV Routing Table At most one entry for each dest. Timer Sequence Table entries Not explicit On-demand w/ route discovery Timer-based deletion for stale routes Notify all sources using failed link via RERR
DSR Source Routes possibly multiple routes in cache min-hop route salvaging Not explicit On-demand w/ route discovery Notify source node following the reverse route when the packet meet the failed link) Gratuitous repair
TBRPF Reportable source tree Link state Rely on partial topology Hop-by-hop Hello Differential Hello Modified Dijkstras alg. Periodic updates Differential updates Report in differential updates
Ant Routing Next-hop utility Multiple routes utility can reflect general qualities of the route Max-utility next hop Hello message No explicit periodic update with randomized agents on-demand update modify utility via backward agents Local repair to salvage the packets
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Plan for the Remaining Year

• Develop clear definition of routing functional
  components
• More detailed mapping of protocols to components
• Incorporate multicast protocols
• Define interfaces among components and with other
  layers
• Characterize the impact of component designs to
  critical routing performance metrics
• Define key mechanisms and design parameters for
  each components
• Identify routing performance metrics that are
  highly correlated to each component
• Identify specific operating conditions under
  which specific component designs are required for
  satisfactory performance
• Based on existing results, analytical techniques
  and focused simulation of existing protocols