1. COS 413 Day 21

2. Agenda Assignment 6 is Due Lab 6 Corrected –1 A, 4 B’s, 1 C, 2 D’s and 1 non submit LAB 7 write-up not corrected –Missing two Assignment 7 Posted –Due Nov 14 Quiz 3 on Nov 14 –Chap 12, 13 & 14 –Same format as before Lab 8 (con't ) in OMS November 12 –Hands-on project 11-1 through 11-4 –We will be working in teams –Write up due Nov 19 Discussion on Cell phone and Mobile Device forensics

3. Rest of Semester Lectures –Nov 7 Chap 13 Assignment 6 Due –Nov 11 Veteran’s Day – No class –Nov 14 Quiz 3 Chap 12, 12 & 13 Assignment 7 Due –Nov 18 Chap 14 –Nov 21 Chap 14 Assignment 8 Due –Nov 25 Chap 15 –Dec 2 Chap 15 Assignment 9 Due –Dec 5 Chap 16 –Dec 9 Chap 16 Assignment 10 Due –Dec 12 Quiz 4 Chap 13, 14 & 15 Labs –Nov 5 - LAB 8 network forensics LAB 7 due –Nov 12 – No lab Lab 8 due –Nov 19 – Final lab part 1 – Kidnapping case –Nov 28 – thanksgiving break –Dec 3 – Final lab part 2 – Kidnapping case –Dec 10 – Final lab part 3 – Kidnapping case Final lab will count as two labs (lab 9 &10) Write-up will be due Dec 12 Capstone presentations –Dec 19 @ 1 PM

4. Guide to Computer Forensics and Investigations Third Edition Chapter 13 Cell Phone and Mobile Devices Forensics

5. Guide to Computer Forensics and Investigations5 Objectives Explain the basic concepts of mobile device forensics Describe procedures for acquiring data from cell phones and mobile devices

6. Guide to Computer Forensics and Investigations6 Understanding Mobile Device Forensics People store a wealth of information on cell phones –People don’t think about securing their cell phones Items stored on cell phones: –Incoming, outgoing, and missed calls –Text and Short Message Service (SMS) messages –E-mail –Instant-messaging (IM) logs –Web pages –Pictures

7. Guide to Computer Forensics and Investigations7 Understanding Mobile Device Forensics (continued) Items stored on cell phones: (continued) –Personal calendars –Address books –Music files –Voice recordings Investigating cell phones and mobile devices is one of the most challenging tasks in digital forensics

8. Guide to Computer Forensics and Investigations8 Mobile Phone Basics Mobile phone technology has advanced rapidly Three generations of mobile phones: –Analog –Digital personal communications service (PCS) –Third-generation (3G) 3G offers increased bandwidth Several digital networks are used in the mobile phone industry

9. Guide to Computer Forensics and Investigations9 Mobile Phone Basics (continued)

10. Guide to Computer Forensics and Investigations10 Main components used for communication: –Base transceiver station (BTS) –Base station controller (BSC) –Mobile switching center (MSC) Mobile Phone Basics (continued)

11. 6-11 © 2007 Prentice-Hall, Inc How Cellular Works Network of cell sites distributed over a wide area –Radio transceiver –Base station controller –Tower and antennas Mobile telecommunications switching office (MTSO) is a cellular switch that places calls from land-based telephones to wireless customers System identification code (SIC or EISN) Controlled channel Phone transmits a registration request MTSO keeps track of the phone’s location in a database

12. 6-12 © 2007 Prentice-Hall, Inc How Cellular Works (Cont’d) MTSO finds you and your phone in the database MTSO picks up frequency that your phone will use in that cell MTSO tells your phone over the control channel which frequencies to use When your phone and the tower switch to those frequencies, the call is connected

13. 6-13 © 2007 Prentice-Hall, Inc Cellular Telephony B E H D I G L K F C M A J N P Handoff O PSTN Mobile Telephone Switching Office 1. Automatic Handoff Between Cellsites O to P as Phone Travels Between Cells

14. Guide to Computer Forensics and Investigations14 Inside Mobile Devices Mobile devices can range from simple phones to small computers –Also called smart phones Hardware components –Microprocessor, ROM, RAM, a digital signal processor, a radio module, a microphone and speaker, hardware interfaces, and an LCD display Most basic phones have a proprietary OS –Although smart phones use the same OSs as PCs

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16. Guide to Computer Forensics and Investigations16 Inside Mobile Devices (continued) Phones store system data in electronically erasable programmable read-only memory (EEPROM) –Enables service providers to reprogram phones without having to physically access memory chips OS is stored in ROM –Nonvolatile memory

17. Guide to Computer Forensics and Investigations17 Inside Mobile Devices (continued) Subscriber identity module (SIM) cards –Found most commonly in GSM devices –Microprocessor and from 16 KB to 4 MB EEPROM –GSM refers to mobile phones as “mobile stations” and divides a station into two parts: The SIM card and the mobile equipment (ME) –SIM cards come in two sizes –Portability of information makes SIM cards versatile

18. Guide to Computer Forensics and Investigations18 Inside Mobile Devices (continued) Subscriber identity module (SIM) cards (continued) –Additional SIM card purposes: Identifies the subscriber to the network Stores personal information Stores address books and messages Stores service-related information

19. Guide to Computer Forensics and Investigations19 Inside PDAs Personal digital assistants (PDAs) –Can be separate devices from mobile phones –Most users carry them instead of a laptop PDAs house a microprocessor, flash ROM, RAM, and various hardware components The amount of information on a PDA varies depending on the model Usually, you can retrieve a user’s calendar, address book, Web access, and other items

20. Guide to Computer Forensics and Investigations20 Inside PDAs (continued) Peripheral memory cards are used with PDAs –Compact Flash (CF) –MultiMedia Card (MMC) –Secure Digital (SD) Most PDAs synchronize with a computer –Built-in slots for that purpose

21. Guide to Computer Forensics and Investigations21 Understanding Acquisition Procedures for Cell Phones and Mobile Devices The main concerns with mobile devices are loss of power and synchronization with PCs All mobile devices have volatile memory –Making sure they don’t lose power before you can retrieve RAM data is critical Mobile device attached to a PC via a cable or cradle/docking station should be disconnected from the PC immediately Depending on the warrant or subpoena, the time of seizure might be relevant

22. Guide to Computer Forensics and Investigations22 Understanding Acquisition Procedures for Cell Phones and Mobile Devices (continued) Messages might be received on the mobile device after seizure Isolate the device from incoming signals with one of the following options: –Place the device in a (empty) paint can –Use the Paraben Wireless StrongHold Bag –Use eight layers of antistatic bags to block the signal The drawback to using these isolating options is that the mobile device is put into roaming mode –Which accelerates battery drainage

23. Guide to Computer Forensics and Investigations23 Understanding Acquisition Procedures for Cell Phones and Mobile Devices (continued) Check these areas in the forensics lab : –Internal memory –SIM card –Removable or external memory cards –System server Checking system servers requires a search warrant or subpoena SIM card file system is a hierarchical structure

24. Guide to Computer Forensics and Investigations24 Understanding Acquisition Procedures for Cell Phones and Mobile Devices (continued)

25. Guide to Computer Forensics and Investigations25 Understanding Acquisition Procedures for Cell Phones and Mobile Devices (continued) Information that can be retrieved: –Service-related data, such as identifiers for the SIM card and the subscriber –Call data, such as numbers dialed –Message information –Location information If power has been lost, PINs or other access codes might be required to view files

26. Guide to Computer Forensics and Investigations26 Mobile Forensics Equipment Mobile forensics is a new science Biggest challenge is dealing with constantly changing models of cell phones When you’re acquiring evidence, generally you’re performing two tasks: –Acting as though you’re a PC synchronizing with the device (to download data) –Reading the SIM card First step is to identify the mobile device

27. Guide to Computer Forensics and Investigations27 Mobile Forensics Equipment (continued) Make sure you have installed the mobile device software on your forensic workstation Attach the phone to its power supply and connect the correct cables After you’ve connected the device –Start the forensics program and begin downloading the available information

28. Guide to Computer Forensics and Investigations28 Mobile Forensics Equipment (continued) SIM card readers –A combination hardware/software device used to access the SIM card –You need to be in a forensics lab equipped with appropriate antistatic devices –General procedure is as follows: Remove the back panel of the device Remove the battery Under the battery, remove the SIM card from holder Insert the SIM card into the card reader

29. Guide to Computer Forensics and Investigations29 Mobile Forensics Equipment (continued) SIM card readers (continued) –A variety of SIM card readers are on the market Some are forensically sound and some are not –Documenting messages that haven’t been read yet is critical Use a tool that takes pictures of each screen Mobile forensics tools –Paraben Software Device Seizure Toolbox http://www.paraben-forensics.com/handheld_forensics.html –BitPim http://www.bitpim.org/

30. Guide to Computer Forensics and Investigations30 Mobile Forensics Equipment (continued) Mobile forensics tools (continued) –MOBILedit! –SIMCon Software tools differ in the items they display and the level of detail

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33. Guide to Computer Forensics and Investigations33 Mobile Forensics Equipment (continued)

34. Guide to Computer Forensics and Investigations34 Summary People store a wealth of information on their cell phones Three generations of mobile phones: analog, digital personal communications service (PCS), and third- generation (3G) Mobile devices range from basic, inexpensive phones used primarily for phone calls to smart phones

35. Guide to Computer Forensics and Investigations35 Summary (continued) Data can be retrieved from several different places in phones Personal digital assistants (PDAs) are still in widespread use and often contain a lot of personal information As with computers, proper search and seizure procedures must be followed for mobile devices

36. Guide to Computer Forensics and Investigations36 Summary (continued) To isolate a mobile device from incoming messages, you can place it in a specially treated paint can, a wave-blocking wireless evidence bag, or eight layers of antistatic bags SIM cards store data in a hierarchical file structure Many software tools are available for reading data stored in mobile devices