CS415 Minithreads Project 5 Overview

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CS415 Minithreads Project 5 Overview

• Adrian Bozdog (Adi)
• adrianb_at_cs.cornell.edu

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What you have to do

• Implement Ad-hoc networking layer
• a version of Dynamic Source Routing alg
• Communication layers should use
  miniroute_send_pkt instead of network_send_pkt
• Routing layer can use network_send_pkt
• A new network_handler routine should deal with
  all packets
• There may be packets (control routing packets,
  packets for other machines) that are not for the
  current machine
• Forwards packets that contain data for the
  current machine to the old network handler

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Routing layer

• Data may be sent through intermediate nodes
• A source uses a routing path to every destination
• Processes three types of routing packets
• Data packets
• Route Discovery packets
• Route Reply packets

User application
TCP-like protocol
UDP-like protocol
Routing
Network
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Routing packets (1)

• Data packets
• Contain the path to the destination
• The intermediate nodes should not involve
  communication layers (i.e TCP, UDP layers)
• Route Discovery packets
• Establish routes from sources to destinations
• Flood the network until the destination is
  reached
• Every packet is flooded for at most
  MAX_ROUTE_LENGTH 1
• Every machine adds itself to the route path
  before broadcasting the network

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Routing packets (2)

• Route Reply packets
• Used to give route information to the sources
• Send by destinations back to the sources
• Flooded through the network until they are
  broadcasted MAX_ROUTE_LENGTH times or reach the
  sources
• Do not change the routes established by the Route
  Discovery packets

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Routing cache

• Avoid discovering a route to the destination for
  every sent packet
• Keeps SIZE_OF_ROUTE_CACHE routes to destinations
• A cached route is used only if it is not older
  than 3 seconds
• Otherwise run the route discovery protocol to get
  the route to destination

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Code change/addition

• Changes to network.h
• Set BCAST_ENABLED to 1
• Set BCAST_ADDRESS
• 192.168.1.255 for ad-hoc network (see
  instructions for setting an ad-hoc network)
• x.y.z.255 for CSUGLAB
• For debugging purposes
• Set BCAST_TOPOLOGY_FILE
• Provide a topology file (see project description)
• Used only in CSUGLAB (not on Jornada/Tablets)
• Add miniroute.h and miniroute.c to your project

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Implementation hints

• There must be at most a single routing discovery
  process for any destination at any time
• Multiple threads should not trigger multiple
  routing discovery processes for the same
  destination
• Only one cache entry for each destination
• Use the route reply packets with the latest
  information (use seq_no for this)
• Use the structures and data-types provided in
  miniroute.h
• Allow other machines that run other students
  code to participate in the routing protocol

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Test Cases

• Use any test from previous steps (project 3 and
  4)
• Write new tests reading application data from the
  terminal
• Add read.c, read.h and read_private.h
• Include read_private.h to minithread.c
• Add miniterm_initialize to minithread_system_initi
  alize
• Test cases should use miniterm_read() to read
  data from the terminal

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Tablets

• Can compile and run tests like CSUGLAB desktops
• Can compile code for Jornada
• Can synchronize with Jornada using ActiveSync
• Run tests between Jornada and the Tablet
• Specify the TCP/IP properties for the Tablet in
  the same way as for Jornada for ad-hoc network
• Specify an Ip address based on your group
• Set Subnet Mask to 255.255.255.0
• Set Gateway to 192.168.1.254
• Install the software used to compile code for
  Jornada ( see Tips for running programs on
  Jornada on CMS)
• Install Handheld PC 2000 SDK

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Project 5 presentation

• Demo slots
• Tuesday April 15 between 6 and 9 pm
• Wednesday April 16 between 6 and 9 pm
• Every group has a slot of 10 minutes
• A test of my choice
• should be compiled and run between Jornada
  machines / Tablet
• should be compiled and run on CSUG desktops
• Set a DEBUG option in the routing layer used to
  print information about messages received by the
  routing layer
• You can sign for a slot on a sign-up sheet
  starting from Thursday afternoon (4119 Upson)