slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
G53SEC PowerPoint Presentation
Download Presentation
G53SEC

Loading in 2 Seconds...

play fullscreen
1 / 30

G53SEC - PowerPoint PPT Presentation


  • 94 Views
  • Uploaded on

G53SEC. Mobile Security GSM, UTMS, Wi-Fi and some Bluetooth. 1. G53SEC. Today’s Lecture: Security in the mobile world GSM 3GPP / UTMS Mobile IPv6 Wi-Fi Bluetooth. 2. G53SEC. Introduction: Mobile computing one of the fastest growing segments of the PC market

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'G53SEC' - kyrene


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

G53SEC

Mobile Security

GSM, UTMS, Wi-Fi and some Bluetooth

1

slide2

G53SEC

  • Today’s Lecture:
    • Security in the mobile world
    • GSM
    • 3GPP / UTMS
    • Mobile IPv6
    • Wi-Fi
    • Bluetooth

2

slide3

G53SEC

  • Introduction:
      • Mobile computing one of the fastest growing segments of the PC market
    • What is a mobile network?
      • Changing physical / geographical location
      • Changing network topology
      • Attached somewhere to a fixed network
      • Wireless communication

3

slide4

G53SEC

  • Introduction:
    • What is different about mobile networks?
      • Low bandwidth – minimise message size and volume
      • Increased risk of eavesdropping
      • Security issues
        • Authentication
        • Privacy
        • Charging

4

slide5

G53SEC

  • Introduction:
    • Mobile services pose new challenges
      • Some derive from technology
      • Some from applications
    • Physical access – no longer a barrier to network
      • - Wi-Fi access to corporate networks

5

slide6

G53SEC

  • Introduction:
    • Current most active mobile technologies
      • GSM
      • 3GPP/UTMS
      • Mobile IP
      • IEEE 802.11
      • Bluetooth

6

slide7

G53SEC

  • Introduction:
    • Other areas of mobile networks with security implications
      • WAP – Wireless Application Protocol
        • Malicious scripting, Infrastructure issues
      • SMS – Short Messaging Service
        • Spam, spoofing, viruses
      • MANETs – Mobile Ad-hoc Networks
        • - Rogue nodes, Security only at academic stage

7

slide8

G53SEC

  • GSM – 220 000 Cell Towers:

8

slide9

G53SEC

  • GSM:
    • 1st Generation Cell Phones
      • Charge fraud – simple authentication
      • Alibi creation – call forwarding
    • GSM – Improvement from 1st generation
      • Good voice quality
      • Cheap end-systems
      • Low running costs
      • etc..

9

slide10

G53SEC

  • GSM:
    • Creation affected by political influences
      • Differing national regulations and attitudes towards cryptography
      • Law enforcement requested ability to wiretap
    • GSM security goals
      • Protection against charge fraud
      • Protection of voice and signal traffic
      • Phone theft tracking

10

slide11

G53SEC

  • GSM:
    • Components
      • GSM user – subscriber in home network
      • Where service requested – serving network
      • Mobile station comprises
        • Mobile equipment
        • Subscriber Identity Module (SIM)
      • SIM card – smart card chip
        • Performs cryptographic operations
        • Stores keys
        • Stores personal data

11

slide12

G53SEC

  • GSM:
    • IMSI – International Mobile Subscriber Identity
      • Unique subscriber identification
    • TMSI – Temporary Mobile Subscriber Identity
      • Used to avoid location tracking
      • Served when device joins a new subnet
    • IMSI catchers
      • Device authenticates to network but not vice versa
      • Catcher masquerades as a base station
      • Collects IMSI numbers

12

slide13

G53SEC

  • GSM:
    • Cryptography
      • Uses symmetric cryptography
      • 3 algorithms
        • A3 – authentication (Provider specific)
        • A5 – encryption (Standardised)
        • A8 – key generation (Provider specific)
    • No official publication of algorithms exists
    • Cryptanalytic attacks do exist

13

slide14

G53SEC

  • GSM:
    • Location Based Services
      • GSM network records location information of mobile equipment
      • Used for various services (e.g. traffic info)
      • Used for emergencies (Medical, Police, etc…)
      • Obligatory in some countries (e.g. the US)
      • Privacy implications

14

slide15

G53SEC

  • GSM Summary:
    • GSM does not transmit secrets in the clear
    • Voice traffic encrypted over radio but not after base station
    • Some privacy protection through TMSI
    • but IMSI catchers exist to avoid TMSI
    • Law enforcement has access to recorded location data

15

slide16

G53SEC

  • GSM Summary:
  • Criticism:
    • Cryptographic algorithms not made public
    • Unilateral authentication
      • Only mobile equipment authenticates to the network
  • Fraud:
    • Revenue flow attacked
    • Roaming fraud
    • Premium rate fraud

16

slide17

G53SEC

  • 3GPP/UTMS:
    • Universal Mobile Telecommunications System
    • Next generation of GSM
    • Besides technical advancements, contains some security enhancements
    • Security architecture similar to GSM
    • Avoids IMSI Catchers
      • - Due to mutual authentication of mobile equipment to the network and vice versa

17

slide18

G53SEC

  • 3GPP/UTMS:
    • Authentication
      • Support for mutual authentication
    • Privacy
      • Increased key sizes
      • Support for securing core network signalling data
      • Enhanced user identity confidentiality
    • Other
      • Integrity of signalling
      • Cryptographic algorithms made public

18

slide19

G53SEC

  • Mobile IPv6:
    • GSM & UTMS have problems with access control due to lack of pre-established relationship
    • In IP if nodes move around:
      • - When IP address kept, data will not reach node at new location
    • - When IP address changes, communication has to be terminated and restarted
    • Mobile IP deals with these issues

19

slide20

G53SEC

  • Mobile IPv6:
    • Mobile node has two addresses
      • permanent Home Address
      • Care of Address – associated with network the node is visiting
    • Addresses consist of location as well as interface identification

20

slide21

G53SEC

  • Mobile IPv6:
    • Home agent – nodes with permanent address within agent's network
    • Foreign agent – nodes visiting network
    • When a node wants to communicate with another node, it uses its home address
    • Packets sent are intercepted by Home agent
    • Home agent uses care-of address advertised by Foreign Agent to communicate with destination node

21

slide22

G53SEC

  • Wi-Fi:
    • Wireless technology generally based on a set of standards called IEEE 802.11
    • A number of standards (a,b,g,n) exist depending on speed and technological improvements
    • A number of security protocols proposed
      • WEP
      • WPA
      • WPA2

22

slide23

G53SEC

  • WiFi:

23

slide24

G53SEC

  • Wi-Fi:
  • Wi-Fi Increasingly used at home and as part of businesses
  • New uses emerge frequently
    • City wide Wi-Fi
    • BT FON

24

slide25

G53SEC

  • Wi-Fi:
    • Many Issues:
      • Incorrectly setup Access Points
        • Encryption
        • Access control
      • Wi-Fi not included in security policies in many institutions
      • - Weak encryption standards used
      • - Rogue Access Points
      • - War-driving

25

slide26

G53SEC

  • Wi-Fi:
    • WEP
      • Key size a major security limitation
      • Algorithm is susceptible to a cryptanalysis attack
      • It uses the RC4 stream cipher algorithm
      • WEP allows certain packet parts to be reused
      • This allows attacker to obtain some known text
      • The rest is only a matter of statistical analysis

26

slide27

G53SEC

  • Wi-Fi:
    • WEP
      • Original attack required hours of collected data to successfully find encryption key
      • 2007 – WEP cracked under 60 seconds by researchers from Germany
    • WPA
      • A quick preliminary solution to WEP issues
      • However vulnerable to a password guessing attack

27

slide28

G53SEC

  • Wi-Fi:
    • WPA2
      • A complete redesign of WLAN security mechanisms
      • Stream cipher RC4 replaced by AES
      • but WPA2 requires new hardware
    • To Remember:
      • For Wi-Fi access points only use WPA2 or in worst case WPA
      • WEP is totally broken!

28

slide29

G53SEC

  • Bluetooth:
    • Technology for wireless ad-hoc networks
    • For short range communications
    • e.g. for keyboards, headsets, etc..
    • Contains cryptographic mechanism for traffic protection between devices
    • Application level attacks exist
      • Bluesnarf exploits flawed implementations of access control – retrieves personal information
    • Viruses are beginning to appear
      • http://www.f-secure.com/weblog/archives/archive-072007.html

29

slide30

G53SEC

  • Summary:
    • Security in the Mobile environment
    • Current mobile technologies

30