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Providing Integrated Ad Hoc Mobility

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Providing Integrated Ad Hoc Mobility Powered By Docstoc
					Research Challenges for Military
Networking

                    Ken Young
                    kcy@research.telcordia.com
                    (973) 829-4928

                    September 6, 2002
Talk Outline
 Background on military networking challenges
  – ARL CTA program
  – DARPA AJCN program
  – CECOM MOSAIC ATD
 Networking technologies
  – Node and domain autoconfiguration
  – Routing
  – Reliable transport
  – Other challenges
 Integration challenges
 Transition challenges
 Conclusions




                                                 Cornell Workshop 6 Sept 2002– 2
Current Battlefield Networks - Tactical Internet


                           Division TOC           Brigade TOC


                  MSE



                                                          Brigade TOC
                  NTDR
                          Upper Echelon                           Battalion
                                                                       TOC
    Brigade TOC

 Battalion
 TOC



             Battalion   EPLRS (Enhanced Position
                  TOC    Location Reporting System)


                                             SINCGARS (Single Channel
                                            Ground and Airborne System)

                                                        Cornell Workshop 6 Sept 2002– 3
             Future Battlefield Networking Concept




Sustaining
  Base




                                                            OTM Enclave




                                                     Sensor Nets


                    OTM Enclave



                                               Cornell Workshop 6 Sept 2002– 4
FCS Networking Implications
 Mobile ad hoc networks must smoothly blend heterogeneous
  physical layers
 Self-organizing and self-managing network operations
 Networking that accommodates directional antennas
 Network sessions must be maintained while on-the-move
 Network survivability with graceful degradation
 High throughput for collaborative C4ISR to support network-
  centric operations
 QoS for real-time traffic with dynamic network topologies
 Indirect routing and dynamic load balancing
 Mitigation of MAC/routing/transport layer vulnerabilities
 Topology control and predictive routing for mobile line-of-sight
  backbones




                                                       Cornell Workshop 6 Sept 2002– 5
Survivable Wireless Mobile Networks
 Objective: Dynamically self-configuring wireless network
  technologies that enables secure, scaleable, energy-efficient,
  and reliable communications
 Research challenges
  – Scalability to thousands of nodes
  – Highly mobile nodes and infrastructure
  – Severe bandwidth and energy constraints
  – Decentralized networking and dynamic reconfiguration
  – Accommodation of high bit-error-rate, wireless networks
  – Seamless interoperability
 Scientific barriers
  – Understanding of trade-offs under bandwidth, energy, processing
    capability, bit-error-rate, latency, and mobility constraints
  – Understanding of interactions between cross-layer algorithms
  – Limited modeling capability for scaling distributed algorithms



                                                          Cornell Workshop 6 Sept 2002– 6
  Node/Network Autoconfiguration

    BB             Config Database                  ACM
                                                     DCDP distributes
                             MySQL                   new configuration

Network GUI          Config Server                  Node
                            YAP low-bandwidth       DRCP configures
                            configuration reports   subnet interfaces
                                                      Preconfigured
 Local GUI                        Interface           node capabilities
 ACM:     Adaptive Configuration Manager
 DCDP:    Dynamic Configuration Distribution Protocol
 DRCP:    Dynamic and Rapid Configuration Protocol
 L-GUI:   Display of local node capabilities and configuration
 N-GUI:   Display of network topology and configuration
 YAP:     Configuration database maintenance and access protocol


                                                       Cornell Workshop 6 Sept 2002– 7
                               Node/Network Autoconfiguration Performance
                               18

                               16
Configuration Time (seconds)
                                                  dense
                               14                 sparse
                               12
                                                                                                                          Autoconfiguration
                               10
                                                                                                                                Time
                               8

                               6

                               4

                               2

                               0
                                    100   200   300   400   500   600   700              800               900   1000
                                                      Number of nodes                                    3500


                                                                                                         3000
                                                                              Bandwidth (bytes/second)


                                                                                                         2500                                                Subnet overhead (refresh=10s)
                                                                                                                                                             Subnet overhead (refresh=30s)
                                      Autoconfiguration                                                  2000
                                                                                                                                                             Network overhead (refresh=10s)
                                          Overhead                                                       1500                                                Network overhead (refresh=30s)


                                                                                                         1000


                                                                                                         500


                                                                                                           0
                                                                                                                 100    200   300   400   500   600   700   800   900
                                                                                                                                                                   Cornell Workshop 6 Sept 2002– 8
                                                                                                                               Number of nodes
Domain Autoconfiguration
 Objective: Autoconfigured domains for scalable, survivable and
  efficient routing, configuration, security and QoS in dynamic
  networks
 Research issues                                 Mountainous terrain
  – Dynamically selecting border nodes
  – Aggregating domain information
  – Algorithms to dynamically decide domain
    membership based on node mobility, roles,...             Unstable links
  – Scalable and robust protocols to create and
    maintain domains in dynamic networks
  – Isolating and resolving faults and intrusions
    using dynamic domain reconfiguration
 Approach                                                           Stable links
  – Hierarchical topological domains built from
    individual interfaces
  – Independent domains for each function
                                                    XX XXX




                                                    Flat terrain
                                                               Cornell Workshop 6 Sept 2002– 9
MANET Routing Hierarchy
                              Backbone Network        Conventional Routing




                              JTRS WNW Subnet                    MANET Routing




                              Dismount Radios                    MANET Routing



Gateway/Border Router Nodes

                      MANET Routing Examples
            • AODV      • OLSR        • FSR      • TORA
            • DSR       • TBRPF       • WARP     • FSLS
            • ZRP       • LANMAR      • DRD      • ....


                                                          Cornell Workshop 6 Sept 2002– 10
Dynamic Border Router

 Enhanced autoconfiguration
                                                  Mountainous terrain
  technology to create and
  maintain domains
  -   DBR automatically selected if node
                                                         Unstable links
      has interfaces in multiple domains
  -   Demonstration on small testbed
      (AODV/RIP & AODV/AODV)
  -   Transition to CECOM MOSAIC ATD
 Automatically selected by ACM                                   Stable links
  -   Developing algorithms to dynamically
      decide domain membership based on
      node mobility, roles, link stability...   XX XXX




                                                Flat terrain


                                                           Cornell Workshop 6 Sept 2002– 11
  Heterogeneous Domain Routing
 Objective: Develop scalable and efficient routing protocols in
  heterogeneous mobile wireless networks
 Approach
   – Configure/reconfigure the
                                     Domain instances     Static,
     network into more homogeneous
                                                          sparse
     routing domains                 Reverse route        domain
   – Design routing modules specific  notification
     to each domain for intra-domain                         Routing modules
     routing
                                                                Link failure
 Challenges                                                    notification
   – Characterizing performance of
                                                                           Highly
     routing strategies in dynamic                                        dynamic
     and Byzantine environments                                           domain
                                    Inter-domain
   – Interactions of routing protocols routing             Domain instances
     at the border nodes
                                                            Probabilistic
   – Developing inter-domain routing
                                                             broadcast
     protocols for routing among
     border nodes

                                             Domain specific routing
                                                            Cornell Workshop 6 Sept 2002– 12
Bandwidth Broker Functional Components
 IP-level topology
   • Config. Database dynamically updates
 Per Class Resource Information
   • Provisioned and available link capacity             Bandwidth Broker
 Call Status Information

 Domain wide QoS policy info                                                         Configuration
                                                        Policy Resource
    • DiffServ functions in nodes                      Database Database               Database
                                                                                          via
QoS Resource Management within domain                                                 YAP Server
     •   Database initialization and update
                                                        Admission Control            Other BBs
     •   QoS Resource configuration in nodes
                                                          & Resource
                                                                NEs
Admission Control into the domain                           Manager
     •   Based on network state, policy & requests                                Applications
     •   Also call/session events across domains                                       via
                                                                                Service Manager
                                                                                      (SM)
                                                     Network Nodes (Routers)
Reliable UDP communication
Reliable UDP avoids TCP congestion control
• Avoids in wireless environment
problems TCP congestion control problems



                                                                        Cornell Workshop 6 Sept 2002– 13
Some Comparative Performance Test Results
                                                  DiffServ/BB
                Single           No
 Service                                         107 VoIP calls
                Class         DiffServ
  Class                                      WRR                Priority

              PLR     Util   PLR    Util   PLR    Util      PLR              Util


AF4 - TCP             67%           0.9% 0.66%     70% 0.73% 80%

AF3 - VoIP 0.64%      80%    30%    56% 0.68%      80% 1.01%               80%

AF2 - Video     0% ~90%      30% ~50% 0.56% ~90% 0.43% ~90%
AF1 - UDP
128-byte        0% 100%      30%    70% 0.67% 100% 12%                     90%
BE - UDP
1024-byte     0.15%   96%    33%    65%    87%     65% 86%                 70%



                                                         Cornell Workshop 6 Sept 2002– 14
Reliable Transport
 Objective: Alternative transport protocols that increase end-to-end
  performance, survivability, and reliability of FCS applications
 Approach                                                            port
   – SCTP (RFC 2960) for FCS environment
                                                              Application
       Partial delivery for differentiated QoS of multiple                          132 (IANA)
        prioritized streams
                                                              SCTP
       Multi-homing and cross-stream data bundling to        IP                 ... IP addresses
        provide load balancing and path selection
       Denial-of-service-resistant connection                Link
        establishment
                                                                                       ...
   – Analyze empirically using SCTP reference      Physical
     implementations
   – Evaluate performance tradeoffs under different
     mobility conditions
   – Define visionary progress of SCTP for FCS
 Research Issues
   – Performance during failover/changeover
   – Performance/bandwidth impact of avoiding abort/restart transport connections
     that support longer term applications
   – Optimal flow control for providing different QoS for application streams using
     same transport connection

                                                                            Cornell Workshop 6 Sept 2002– 15
Improved Transport Layer Congestion Control

• Explore new transport layer
 alternatives for survivable
 wireless mobile networks
• Capitalize on opportunity to
 influence SCTP standard
• Split Fast Retransmit
 Changeover-Aware
 Congestion Control (SFR
 CACC) algorithm submitted
 as IETF Internet Draft
• Exploit transport layer multi-
  homing for uninterrupted
  end-to-end communication
• Significantly enhances transport layer’s ability to support
  persistent on-the-move sessions for FCS networks

                                                   Cornell Workshop 6 Sept 2002– 16
Other Networking Research Challenges
 Data Link Layer
   – Energy-efficient topology control and MAC
   – Self-organizing subnets
 Quality of Service
   – Estimating bandwidth and delay on individual links
   – Allocating bandwidth and delay to meet end to end objectives
   – QoS coordination across layers (physical to application)
 Multicast
   – With mobility, QoS, etc.
   – Reliable multicast
 Security
   –   Distributed dynamic trust establishment and key management
   –   Efficient, robust message authentication
   –   Intrusion detection and mitigation
   –   Vulnerability assessment
 Network Management
   – Fault detection and localization
   – Self-healing
   – ....


                                                                    Cornell Workshop 6 Sept 2002– 17
Integration Example – MOSAIC AMPS
                                               Protocol/
  Function        Subfunction                  Entity      Source              Code
                  Subnetwork                   DRCP        Telcordia           C++
  Configuration   Network                      DCDP        Telcordia           C++
                  Management                   ACM         Telcordia           Java
                                               SIP         Telcordia           Java
                  Location
  Mobility                                     DDNS        Linux               C
  Management                                   DMA         Telcordia           C
                  Continuous connectivity
                                               Mangler     Telcordia           Java
                  Unicast                      RIP         Zebra               C
                  Ad hoc unicast               AODV        Mad-hoc/NIST        C
  Routing         Multicast                    HLIM        Telcordia           C
                  Ad hoc multicast             MAODV       U. Maryland         C
                  Border router                DBR         Telcordia           C
  Reliability     Transport                    SCTP        Siemens             C
                  Reporting                    YAP         Telcordia           Java
  Visualization   Local                        L-GUI       Telcordia           Java
                  Network                      N-GUI       Telcordia           Java
                  Authentication, key exchange IKE         freeswan            C
  Security
                  Integrity, privacy           IPSec       freeswan            C
                  802.11                       SQC         Telcordia           C
  QoS             IP                           DiffServ    Telcordia           C
                  Management                   BB          Telcordia           Java

                                                               Cornell Workshop 6 Sept 2002– 18
     Transition Example - JTRS SCA 2.0 View
                                                                                                  Applications
                                                                                              Core Framework (CF)
                                                                                  OE           Commercial Off-the-Shelf
                                                                                                     (COTS)

     Non-CORBA                                           Non-CORBA                                           Non-CORBA
       Modem                                               Security                                             Host
                                                         Applications                 AMPS
                                                                                     AMPS                    Applications
     Applications                                                                    AMPS
                 Non-CORBA                               Non-CORBA                             Non-CORBA
RF               Modem API                               Security API                           Host API

       Modem      Modem      Link, Network       Security Security Security       Link, Network      Host     Host
     Applications Adapter     Applications       Adapter Applications Adapter      Applications     Adapter Applications
         Modem API           Link, Network API         Security API                 Link, Network API
                               Core Framework IDL (“Logical Software Bus” via CORBA)


         CORBA ORB &               CF                           CORBA ORB &                 CF
            Services            Services &                         Services              Services &
          (Middleware)         Applications                      (Middleware)           Applications
               POSIX Operating System                                   POSIX Operating System
       Network Stacks & Serial Interface Services             Network Stacks & Serial Interface Services
           Board Support Package (Bus Layer)                     Board Support Package (Bus Layer)

       Black (Secure) Hardware Bus                                                  Red (Non-Secure) Hardware Bus




                                                                                               Cornell Workshop 6 Sept 2002– 19
Transition Example - FCS




                           Cornell Workshop 6 Sept 2002– 20
Conclusions
 Networking challenges at multiple layers; interactions between
  layers key in wireless mobile networks
  – Data link
  – Network
  – Transport
 What’s most important? Current FCS LSI opinion is that highest
  risk areas are:
  – Mobility
  – Heterogeneous QoS
  – Scalability
 Also many interesting research issues in the “seams”
  – Integration
  – Transition




                                                     Cornell Workshop 6 Sept 2002– 21

				
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