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Programmable Handoff in Mobile Networks

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Programmable Handoff in Mobile Networks Powered By Docstoc
					Accelerating Service Creation
       and Deployment
     in Mobile Networks




        Michael E. Kounavis
          COMET Group,
        Columbia University
    Our position:

 mobile networks will become
  programmable!
 migration paths to new technologies
  needed
    – e.g., software radios create wireless physical layers
      dynamically

   we extend programmability to the
    signaling plane and MAC layer
  Example of a new service


   GSM access                 IEEE 802.11
     network                  Wireless LAN

              beacons that
              identify the
             access network
              architecture

„programmable‟
   PCS phone
Example of a new service


GSM access          IEEE 802.11
  network           Wireless LAN




               PCS phone
              moves to the
             wireless LAN
Example of a new service


GSM access              IEEE 802.11
  network               Wireless LAN




  access network injects
IEEE 802.11 software radio
   and mobile IP support
Example of a new service


GSM access             IEEE 802.11
  network              Wireless LAN




        PCS phone becomes
     a wireless Internet host!
Example of a new service


GSM access       IEEE 802.11
  network        Wireless LAN




   Reflective Handoff
    Approach

   we propose a programmable
    architecture that consists of:
    – a binding model.
    – a service creation environment.

   applications:
    – „multi-handoff‟ access networks
    – reflective handoff
    – programmable MAC
    Binding Model

                                  beaconing systems
                                  beaconing systems
  handoff control is
decomposed into basic          measurement systems
                                 beaconing systems
      functions
                               detection algorithms
                                 beaconing systems

  adapters separate              handoff adapters
                                  beaconing systems
handoff detection from
  handoff execution                                   mobility
                             session
                            session       session
                                         wireless       session
                            rerouting    rerouting      state
                                                       rerouting
                           rerouting    transport
                                                     management

  software radios „open         physical/data link layers
                               physical/data link layers
  up‟ the physical layer
    Service Creation Environment

   composes mobile network services
    – CORBA-based
    – MAC layers constructed from dynamic link libraries

   profilers
    – generate service scripts automatically

   service controllers
    – compile scripts
    – resolve object bindings
    – create mobile network services
  Dynamic Binding

                                                beaconing systems
                                                beaconing systems
                       service
                      service
                     controllers
                    controllers
                                             measurement systems
                                               beaconing systems
             profiling         binding
              scripts           calls        detection algorithms
                                               beaconing systems

                       service
 profilers
profilers             service
                     controllers               handoff adapters
                                                beaconing systems
                    controllers



                                           session      session     mobility
                                                                      session
                                          session      wireless
                                          rerouting    rerouting      state
                                                                     rerouting
                                         rerouting    transport
                                                                   management
                       service
                      service
                     controllers
                    controllers
                                              physical/data link layers
                                             physical/data link layers
A Profiling Script
# part 1: service declarations
new_service    beaconing_system;
new_service    measurement_system;
new_service    detection_algorithm;
new_service    handoff_execution_interface;
new_service    mobility_management_system;

# part 2: variable declarations
access_points = {“cymbal.comet.columbia.edu”, “voice.comet.columbia.edu”};
mobility_agent = “cvn1.comet.columbia.edu”;
beacon_interval = 100;
query_interval = 300;
max_requests = 500;

# part 3: object activation
load_object “BeaconProducer” $beaconing_system $access_points $beacon_interval;
load_object “MeasurementProducer” $measurement_system $access_points $query_interval;
load_object “MAHO_APSNRMonitor” $measurement_system $access_points $max_requests;
load_object “MAHO_DetectionAlgorithm” $detection_algorithm $access_points $max_requests;
load_object “HandoffExecutionInterface” $handoff_execution_interface $access_points;
load_object “MAHO_Adapter” $handoff_execution_interface $access_points;
load_object “MobilityAgent” $mobility_management_system $mobility_agent $max_requests;
load_object “AP_Datapath” $mobility_management_system $access_points $max_requests;
load_object “AP_MobileRegistrationDB” $mobility_management_system $access_points $max_requests;

# part 4: object bindings
bind_objects “MAHO_APSNRMonitor”@$access_points => “MAHO_DetectionAlgorithm”@$access_points;
bind_objects “MAHO_APSNRMonitor” @$access_points => “MeasurementProducer”@$access_points;
bind_objects “MAHO_DetectionAlgorithm”@$access_points => “HandoffExecutionInterface”@$access_points;
bind_objects “HandoffExecutionInterface”@$access_points => “MAHO_Adapter”@$access_points;
bind_objects “MAHO_Adapter”@$access_points -> “MobilityAgent”@mobility_agent;
bind_objects “MAHO_Adapter”@$access_points -> “AP_Datapath”@$access_points;
bind_objects “MAHO_Adapter”@$access_points -> “AP_MobileRegistrationDB”@$access_points;
end;
    „Multi-handoff‟ Access network

   supports multiple styles of handoff
    control simultaneously
    – Mobile Controlled HandOff (MCHO)
    – Mobile Assisted HandOff (MAHO)
    – Network Controlled HandOff (NCHO)
 connects a wide range of mobile
  devices
 built upon open programmable access
  points and switches/routers
    Handoff Detection

   mobile controlled handoff
    – mobile device takes measurements and detects mobility

   mobile assisted handoff
    – mobile device takes measurements only
    – access network detects mobility

   network controlled handoff
    – access network takes measurements and detects mobility
    Handoff Execution

   session rerouting
    – managed by „mobility agent‟ objects
    – open programmable switches allow the establishment,
      removal, rerouting, or adaptation of user flows
   wireless transport
    – „datapath objects‟ dispatch value-added QOS algorithms
      in wireless access points on-demand
   mobility state
    – namespace allocations
    – QOS adaptation profiles
    – wireless transport preferences
     Distributed Algorithms

                 NCHO_DetectionAlgorithm                    MAHO_DetectionAlgorithm                                   MCHO_DetectionAlgorithm

                                                                            (b -5) measureReport ()
 (a -5) reportMobileSNR ()

                                                                                               (b -3) measureON ()                (c-2) get
                                                                       (b -2) detectHandoff () (b -6) measureOFF ()
        (a -3) getMobileSNR() (a-2) detectHandoff ()                                                                              APSNR()
      NCHO_APSNRMonitor                                     MAHO_APSNRMonitor MAHO_MDSNRMonitor                        MCHO_MDSNRMonitor




     (a -4) queryBeaconInfo ()                                         (b -1) queryBeaconInfo() (b -4)queryBeaconInfo ()           (c-1) query
                                 (a-1) queryBeaconInfo ()                                                                          BeaconInfo()

     MeasurementProducer                                     MeasurementProducer MeasurementProducer                   MeasurementProducer




 neighboring
                          access point                            access point            mobile device                      mobile device
access points

            (a) network                                                      (b) mobile                                     (c) mobile
             controlled                                                       assisted                                       controlled
              handoff                                                         handoff                                         handoff
Reflective Handoff
                                    mobile IP enabled
     home agent              host    internetwork

                                        gateway #2

                       gateway #1
       access                            access
     network #1                        network #2



              access                   access
               point                    point

loading a signaling module
    Design

   we use beacons as a common signaling
    channel
    – beacons carry unique identifiers characterizing access
      networks
   mobile devices maintain signaling
    module caches
    – if a module is not cached it is loaded dynamically
   module loaders
    – schedule the transmission of signaling modules over the
      air interface and provide security
    Experimental Environment

   multi-handoff access Network has been
    developed on the Mobiware testbed
    –   four ATM Switches,
    –   four wireless access points, all 300 MHz pentium PCs,
    –   2 Mbps WaveLAN radios
    –   high speed notebooks
   reflective handoffs have been tested across
    the Mobiware and Cellular IP access networks
    – Cellular IP testbed:
       • three wireless base stations, all 300 MHz pentium PCs,
       • interconnected with the Mobiware testbed via 100 Mbps
          ethernet LAN
   mobility emulator used for scalability analysis
    Implementation Issues

   multi-handoff access network
    – „oneway‟ CORBA calls increase the level of parallelism in
      object interactions
    – call aggregation techniques reduce handoff latency

   reflective handoff
    – signaling module loading latencies
    – forwarding delay at the new access network compensates
      for the handoff completion time
    – soft state module caches
Multi-handoff Access Network
Performance

                wireline     wireless    measurement      total
               connection   connection    collection    latency
                 latency      latency      latency      (msec)
                 (msec)       (msec)        (msec)


    mobile      22  1       19  1          _          41  1
  controlled
   handoff

    mobile      21  1       20  1       709  65     750  65
   assisted
   handoff

   network      22  1       20  1       641  59     683  59
  controlled
   handoff
Handoff Latency with Call
Aggregation, 6 handoffs/sec
Handoff Latency with Call
Aggregation, 2 handoffs/sec
 Reflective Handoff Results




Cellular IP to Mobiware   Mobiware to Cellular IP
    Related Work

   Virtual radios (MIT)
    – Programmability of the physical layer

   Mobiware Toolkit (Columbia)
    – Programmable support for adaptive mobile networking

   Active Wireless Networks (U. Kansas)
    – Active protocol classes for wireless networks
    People

 Michael E. Kounavis (Columbia U.)
 Andrew T. Campbell (Columbia U.)
 Gen Ito (NEC, Japan)
 Giuseppe Bianchi (U. Palermo)
    References

   M. E. Kounavis, A. T. Campbell, G. Ito, and G. Bianchi,
    “Programmable Handoff in Mobile Networks”, ACM/Baltzer
    Mobile Networks and Applications, to be published

   G. Bianchi, and A. T. Campbell, “A Programmable MAC for
    Adaptive Quality of Service Control”, IEEE Journal on
    Selected Areas in Communications, March 2000.

   Mobiware Mobility Emulator Source Code Distribution:
    http://comet.columbia.edu/mobiware/emulator
Thanks for listening!

				
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posted:10/26/2011
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