EEC 687/787 - Mobile Computing (Fall 2011)


Instructor

Prof. Yu Chansu, e-mail: c.yu91@csuohio.edu, Office: SH 437, phone: 2584, Office hour: MW 2-4pm

Course Information

Download here (including syllabus, grading policy, labs, course schedule, etc.)

Reading Material for Midterm #2

  • IEEE 802.11 spec (1999), “PCF,” Ch. 9.3
  • IEEE 802.11 spec (1999), “MAC sublayer management entity,” Ch. 11.1~3

  • RFC 3344, IP Mobility Support for IPv4, C. Perkins, Ed., 2002, http://www.ietf.org/rfc/rfc3344.txt (Section 3.6 ~ 8)

  • Reference: H. Woesner, J.-P. Ebert, M. Schlager, and A. Wolisz, "Power-Saving Mechanisms in Emerging Standards for Wireless LANs: The MAC Level Perspective," IEEE Personal Communications, Vol. 5, Issue 3, pp. 40-48, Jun. 1998

  • Reference: C. E. Perkins, "Mobile-IP", in Communications Magazine, May 1997

Reading Material for Final Exam (Lecture notes must be covered)

  • Quizzes
  • MAC and carrier sensing mechanism (5 points): IEEE 802.11 spec (1999), “DCF & PCF,” Ch. 9.2 & 9.3
  • IEEE 802.11 MAC (10 points): IEEE 802.11 spec (1999), “DCF & PCF,” Ch. 9.2 & 9.3
  • IEEE 802.11 MAC Frame Format and Procedure (10 points): IEEE 802.11 spec (1999), “MAC Frame Formats,” Ch. 7.1
  • IEEE 802.11 MAC Management (5 points): IEEE 802.11 spec (1999), “Synchronization & Power Management,” Ch. 11.1 & 11.2
  • Performance anomaly in IEEE 802.11 MAC (15 points): Section II, http://academic.csuohio.edu/yuc/papers/PID999868.pdf
  • Mobile IP (20 points): C. E. Perkins, "Mobile-IP", in Communications Magazine, May 1997
  • MANET Routing (20 points): D. B. Johnson and D. A. Maltz, "Dynamic Source Routing in Ad Hoc Wireless Networks," Mobile Computing, edited by T. Imielinski and H. F. Korth, Kluwer Academic Publishers, 1996.
  • TCP in Mobile Networks (15 points): R. Caceres and L. Iftode, "Improving The Performance of Reliable Transport Protocols in Mobile Computing Environments," IEEE Journal of Selected Areas in Communications, pp. 850-857, June 1995.

Class projects

  • Amarnadh Oleti, Daljeet Singh, Praveen Reddy, Capture and Retransmit I/Q Data using GNU radio and USRP - Mid-report, Final report
  • Dan Levtonyuk, Emanuel Papp, Xiang Li, BER Performance of DSSS Technique under Periodic Jamming - Mid-report, Final report
  • Brian Krupp, Limei Hou, Ns2 SetDest Acceleration Enhancement - Mid-report, Final report
  • John Merchant, Kevin Kelsey, Scanner using GNU Radio - Mid-report, Final report
  • Asha Mariam Iype, Shashanka C. D., Video transmission using USRP - Mid-report, Final report
  • Rakesh Vanam, Varun Venkatraman, Implementation of Co-operative Communication using GNU-Radio - Mid-report, Final report

Previous class projects

Example class projects

 

Lecture notes and Announcements

  • Week 01 (Aug. 29): Lecture I: Overview of mobile computing
  • Week 01 (Aug. 31): Lecture II: Physical layer  
    • Bring your thumb drive larger than 5GB to copy the VMware image. If you wish to install by yourself, here are the version numbers: Ubuntu 10.04, Ns-2 2.34, and GNU Radio 3.30.
  • Week 02 (Sep. 7): Lab I: Mobile network simulation using ns-2
    • Files: ex6sta.tcl, fil.awk, fil2.awk, fil4.awk, fil6.awk
    • Lab I Report (Due Sep. 12):
      • PDR analysis: What is the overall PDR? What is the PDR for WT1-WT2, WT3-WT4 and WT5-WT6? Discuss the results.
      • Delay analysis: Send me delay.awk. What is the average packet delay? What is the packet delay for WT1-WT2, WT3-WT4, and WT5-WT6? Discuss the results.
      • Read: Mandatory reading’s
      • Read: Ns2 manual, “Mobile networking in ns,” Ch. 16 (http://www.isi.edu/nsnam/ns/doc/ns_doc.pdf)
      • Read: Ns2 manual, “Trace and Monitoring support,” Ch. 23
  • Week 03 (Sep. 12): Lecture III: Wireless propagation
  • Week 03 (Sep. 14): Lab II: Wireless propagation
    • Files: rate.tcl
    • Lab II Report (Due Sep. 19):
      • Run the simulations for all TX-rate. Obtain the aggregate CBR throughput for each run. And draw a chart drawing throughput versus TX-rate
      • Research: For the same data rate, change the capture threshold to see its effect on performance
      • Research: Modify mac-802_11.cc file so that the receiver gets a new packet (p) if Sp/IpktRx>CPThresh. Observe how it improves the performance. Do not forget to explain and discuss the results.
      • Read: WLAN: A. Kamerman and L. Monteban, “WaveLAN-II: A High-Performance Wireless LAN for the Unlicensed Band,” Bell Labs Technical J., pp. 118-133, Summer 1997.
  • Week 04 (Sep. 19): Lecture IV: Medium access control
  • Week 04 (Sep. 21): Lab III: GNU radio/ USRP software radio platform (Sample Report)
    • Files: base.py, base_gui.py (change the mode or attribute of the file to make it executable - "$ chmod 0755 base.py")
    • Lab III Report (Due Sep. 26)
      • Complete the experiment through step 17. Experiment the dial tone example and test with different values of source (frequency and magnitude).
        a) In step 10, how much can you drop the sample rate?
        b) In step 15, explain the parameters for the high pass filter.
        c) Add “Noise” block (where to add?) to see its effect on the sound and FFT.
      • Read “The Universal Handset,” IEEE Spectrum, April 2009 (http://spectrum.ieee.org/computing/embedded-systems/the-universal-handset) and “PPR: Partial Packet Recovery for Wireless Networks” to write one-page comment on the software radio.
  • Week 05 (Sep. 26): Lecture V: IEEE 802.11 (revised)
  • Week 05 (Sep. 28): Lab IV: BER performance with GNU radio & Lab procedure (Sample Report)
    • File: am_usrp710.zip
    • Lab IV Report (Due Sep. Oct. 3)
      • BER performance with different digital modulation schemes
        a) In step 2, explain the numbers 0.707, 0.630, 0.562, 0.501, 0.446, 0.398, 0.354, 0.316, 0.282, 0.251, and 0.224 which are used to test the case for SNR=0dB, 1dB, … , 10dB, respectively.
        b) Explain the symbol table for 4-ASK in step 4. What is the symbol table for QAM in step 5?
        c) Complete and explain the experiment for QAM.
        d) Plot the BER vs SNR curve for ASK, 4-ASK, and QAM (steps 2, 4, and 5).
        e) Explain and compare your observations with the scope and constellation display in steps 3, 4 and 5.
        f) Discuss the differences between BER and SER (symbol error rate).
        g) Discuss the differences between SNR and Eb/No, where Eb and No denotes energy per bit and noise per Hz.
      • AM receiver (an analog modulation scheme)
        h) Complete steps 6-10 to hear the AM station pre-recorded through a USRP.
        i) Explain Rational Resampler in step 11.
        j) What other stations (which frequency) do you hear in step 13?
        k) Send me the final grc file in step 14 with your report.
  • Week 06 (Oct. 3): Self study
  • Week 06 (Oct. 5): Midterm exam #1
  • Week 07 (Oct. 10): No class (Columbus Day)
  • Week 07 (Oct. 12): Lab V: MAC Performance (Sample Report)
    • File: cwfixed.tcl
    • Lab V Report (Due Oct. 17)
      • MAC
        a) Present the idea and explain why it improves network performance
        b) Explain how it is implemented in ns-2
        c) Present results (charts)
        d) Discussions and conclusions
      • Aloha
        d) Explain how it is implemented in ns-2
        e) Present results (maximum throughput)
        f) Comparison with 802.11 MAC
  • Week 08 (Oct. 17): Lecture VI: IEEE 802.11 Management
  • Week 08 (Oct. 19): Lab VI: Mobility and Traffic Scenarios in ns-2 & Lab procedure (Sample Report)
    • File: e2.tcl, fil2.awk, fil4.awk, fil6.awk
    • Lab VI Requirements (Due Oct. 24)
    • 1) Mobility scenario

    • a) Read ~/ndep-utils/cmu-scen-gen/setdest/setdest.{cc, h}

    • b) Report results of step 7 (PDR and plot).

    • c) In step 8, explain the statistics at the end of the generated mobility file.

    • d) Discuss the two versions of setdest in step 9. What is the problem with the first version of setdest? (Reference: Random Waypoint Considered Harmful, IEEE Infocom, 2003)

    • e) Complete and report step 10.

    • f) Discuss how you can implement the two UAV mobility models described in the paper entitled “Mobility models for UAV group reconnaissance applications,” IEEE ICWMC 2006 using setdest. They are Random mobility model and Distributed Pheromone Repel Mobility Model.

    • 2) Traffic scenario

    • a) Read ~/ndep-utils/cmu-scen-gen/cbrgen.tcl

    • b) A different seed in cbrgen.tcl produces different traffic pattern. Discuss what’s been changed (randomized)?

    • c) Complete and report step 13.

  • Week 09 (Oct. 24): Lecture VII: IP Networking
  • Week 09 (Oct. 26): Lab VII: Benchmark test with GNU Radio/USRP (Sample Report)
    • Lab VII Requirements (Due Oct. 31)
    • 1)      Read the document entitled “The USRP under 1.5X Magnifiying Lens!” (http://gnuradio.org/redmine/attachments/129/USRP_Documentation.pdf) to know more about the USRP hardware and to answer the following questions.

      a)      When running a gnuradio program, it often displays "O" "U" "u" "a" characters on the screen. What do they mean?

      b)      USRP does not have a boot ROM. How does it boot itself?

      c)       How can we change the FPGA configuration? Which tool can be used?

      2)      Browse the Ettus website (USRP manufacturer, http://www.ettus.com/) to know their products and to answer the following questions.

      a)      What is the difference between TXRX and RX2 in RFX2400 daughterboard?

      b)      Explain the Universal Hardware Driver (UHD)

      3)      Benchmark Test

      a)      Tune to 11 802.11b channels. (802.11g uses the same set of channels.) Could you identify the channels that are used in the vicinity? If yes, which channels are they? If no, why not?

      b)      With benchmark_tx.py running and the fft display, what is the optimal transmitter amplitude? According to the help ($ benchmark_tx.py --help), amplitude ranges from 0 to 1.

      c)       With benchmark_tx.py running and the fft display, what is the optimal receiver gain?

      d)      With benchmark_tx.py and benchmark_rx.py running, measure the packet error rate. Estimate the bit error rate? (To convert from PER to BER, you need to know the packet size.)

      e)      Plot a chart that shows BER versus transmit amplitude.

      f)       With benchmark_tx.py and usrp_fftp.py/oscope.py, explain your observations comparing different modulation schemes.

  • Week 10 (Oct. 31): Lecture VIII: Mobile IP
  • Week 10 (Nov. 2) Lab VIII: TUN/TAP interface with GNU Radio/USRP (Sample Report)
    • Lab VIII Requirements (Due Nov. 7)

      1) In non-contention scenario, measure RTT and compare it with RTT between PC and csuohio.edu via Ethernet. Measure error rate and compare. And discuss the ersults.

      2) Understand the CSMA implementation in tunnel.py

      3) Test results several carrier detect threshold in the code and discuss

      4) In contention scenarios, compare the result (RTT, error rate) with no-contention scenario

      5) Explain how you can implement the detection of collisions in the context of tunnel.py

      6) Read the following two papers and discuss issues including why it is difficult to implement CSMA in USRP/GNU Radio platform

      Enabling MAC Protocol Implementations on Software-defined Radios, G. Nychis, S. Seshan, P. Steenkiste, T. Hottelier, Z. Yang (CMU), NSDI '09.

      An Experimental Study of Network Performance Impact of Increased Latency in Software Defined Radios T. Schmid, O. Sekkat, and M. B. Srivastava, WinTECH 2007.

  • Week 11 (Nov. 7): Self-study
  • Week 11 (Nov. 9): Midterm exam #2
  • Week 12 (Nov. 14): Lecture IX: Mobile IP (the same lecture note as above)
  • Week 12 (Nov. 16): Lab IX: Mobile IP and variable tracing in ns-2 (Sample Report)
    • File: infra.tcl, fil_tcp.awk
    • Lab IX Requirements (Due Nov. 21)
    • 1) With infra.tcl & fil_tcp.awk, explain when and why throughput changes. Also, describe what you observed with nam animation.

      2) Repeat the same scenario of infra.tcl but with UDP traffic. Plot a chart that compares throughput of TCP, UDP (0.05), UDP (0.01) and UDP (0.005) and discuss the differences.

      3) With the TCP traffic in infra.tcl, trace the variable using the periodic probing method and variable tracing method. Plot the chart that shows both of them and explain the differences between the two methods.

      4) Write a 1-page discussion on “Parasitic computing” (Nature, 412: 894-897, 2001, by Barabasi et al.).

  • Week 13 (Nov. 21): Lecture X: Mobile Ad hoc Network (MANET)
  • Week 13 (Nov. 23): Lab X: MANET simulation using ns-2 & Lab procedure (Sample Report)
    • File: manet-test.tcl, manet-test2.tcl, manet-aodv.sh, manet-dsr.sh, mob, traffic
    • Lab X Requirements (Due Nov. 28)
    • 1) Comparison of MANET routing algorithms

      a) Answer questions in step 2: Where are initial positions of the three nodes? When do they start moving? Do they pause some time between movements? What are the three nodes’ first waypoints and their speeds? After reaching the waypoints, when do they move again? In “traffic”, which node is the source and which node is the destination? When does the traffic start? What is the packet size?

      b) Describe your observations in step 3 (DSDV). Do you observe that the traffic does not go through in the middle of the simulation but does it as time progresses? What else do you observe? Also, describe your observations with AODV and DSR in steps 5 and 6. Explain the differences.

      c) With DSDV, how often does node 0 send the message in step 4? Is this the same for other nodes? Are the message sizes the same? If not, why?

      d) Presents PDR, average packet delay, routing control overhead in terms of bytes, and normalized routing overhead of DSDV, AODV and DSR in steps 4, 5 and 6.

      e) According to DSR trace file format, which additional information about DSR does the trace tell you?

       2) Performance study in a (relatively) large-scale MANET

      a) Plot performance metrics for both DSR and AODV versus pause-times, for each CBR Load. State if any peculiar behavior is observed in steps 8 and 9.

       3) Confidence in your simulation results

      a) What is CI with 100% CL?

      b) What is the equation for CI corresponding to 99% CL?

      c) In step 10, what are the 10 seed numbers (including 1) you used and the 10 PDR values? What is the mean and standard deviation of PDR measurements? What is your CI with 95% CL? Discuss if this CI is satisfactory.

  • Week 14 (Nov. 28): Lecture XI: Transport control protocol (TCP)
  • Week 14 (Nov. 30): Lab XI: Mobile TCP in ns-2 (Sample Report)
    • File: tcp_simple.tcl, fil2tcp.awk, fil3tcp.awk
    • Lab XI Requirements (Due Dec. 5)
    • 1) Explain the wired network scenario. Show and discuss the results.

      2) Write a tcl script that simulates TCP traffic in a (static) wireless network. Plot a chart that shows throughput over time. Discuss the results.

      3) Do the same simulation using CBR traffic (UDP). Plot a chart that shows throughput over time. Discuss the differences between the throughput charts with TCP and CBR traffic.

      4) Write a tcl script that simulates TCP traffic in a (mobile) wireless network. Plot a chart that shows throughput over time. Discuss the results.

      5) Plot a chart that shows cwnd over time using the variable tracing method learned from a previous lab. Discuss the results.

      6) Do the similar simulation using CBR traffic (UDP). Plot a chart that shows throughput over time. Discuss the differences between the throughput charts with TCP and CBR traffic.

  • Week 15 (Dec. 5): Lecture XII: Mobile TCP
  • Week 15 (Dec. 7): Project presentation
  • Presentation must be based on powerpoint slides (~20 slides) and should be no more than 20 minutes excluding Q&A

  • Order of presentations

    • Amarnadh Oleti, Daljeet Singh, Praveen Reddy, Capture and Retransmit I/Q Data using GNU radio and USRP

    • Dan Levtonyuk, Emanuel Papp, Xiang Li, BER Performance of DSSS Technique under Periodic Jamming

    • Brian Krupp, Limei Hou, Ns2 SetDest Acceleration Enhancement

    • John Merchant, Kevin Kelsey, Scanner using GNU Radio

    • Asha Mariam Iype, Shashanka C. D., Video transmission using USRP

    • Rakesh Vanam, Varun Venkatraman, Implementation of Co-operative Communication using GNU-Radio

  • Week 16 (Dec. 12): Final exam (Please see the top of this page for coverage.)