PERSONAL FIREWALL IN MOBILE PHONE

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PERSONAL FIREWALL IN MOBILE PHONE

• Edina Arslanagic

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Agenda

• Background
• Problem Statement, Limitations
• Solution Useful functions in personal firewall
• Approach Personal firewall essence
• Methods Implementation, Filtering and mobile
  phone functionality
• Conclusion

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Background

• This master thesis is given by Ericsson AS and
  gives an evaluation of a need for personal
  firewall in mobile phone
• In todays commercial products, personal firewall
  in mobile phone does not exist
• Need for personal firewall is real, especially
  during Internet connectivity and in downloading
  Java applications

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Problem statement

• Proposal of which personal firewall functions for
  PC (Windows and Linux) that could be useful in
  mobile phone
• The essence of personal firewall in mobile phone
• Different connection types
• Personal firewall implementation
• Filtering of packets
• Mobile phone underlying functionality

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Solution

• Following functions are proposed to be useful in
  personal firewall
• Monitor incoming traffic, filtering and blocking
• Monitor outgoing traffic
• Detection intrusion attempts
• Port scan detection and logging

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Solution cont.

• Active Content nuisance
• Time Control and Account manager
• Trusted IPs
• Forwarding
• JavaScript Pop-Up blocker
• Updating function for a new version

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Approach

• Personal firewall with its useful functions is
  essential
• Prevent attacks from the network
• Prevent from malicious software Personal firewall
  with integrated AV gives best protection against
  malicious software
• Prevent so called billing attack

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Approach cont.

• Support mobile phone standard functions, specific
  functions and P2P services over IP
• Protect mobile phone during Internet connectivity
  and in downloading applications
• Protect devices in different connections types

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Approach cont.

• Personal firewall is essential in the scenario of
  multihoming when information is forward between
  different connections (e.g., IP forwarding
  between Internet and Intranet)

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Method 1 Implementation of personal firewall

• Personal firewall can be implemented in two
  possible ways
• As software in mobile phone (suitable for all
  connection types), configured by user and
  requires upgrade of software for all mobile phone
  types (except PDA) in the case of updating for a
  new version
• In GGSN and mobile phone (best suitable for
  GPRS/UMTS), (pre) configured by user and does not
  require upgrading in the case of updating

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Method 1 cont.

• If personal firewall is implemented in mobile
  phone, it has to provide certain functionality
• Servers, applications and IPs mobile phone trusts
• Support pop-ups filters
• Updating for a new version
• Support application authentication
• Recognition if the application will start client
  or server

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Method 1 cont.

• If personal firewall is implemented in GGSN and
  mobile phone, operators offer services in
  personal firewall, and user can extend these
  rules. Mobile phone must support TFT in GGSN.

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Method 2 Filtering of packets

• Filtering of packets can be done
• In IP layer (Network) fast since filtering is
  based on header information, less secure
• At application layer (Application) slow but more
  secure since filtering is based on the whole
  packet content

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Method 2 cont.

• In personal firewall that includes a part of IP
  stack responsible for filtering faster since
  filtering is done in personal firewall but still
  less secure

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Method 3 Mobile phone underlying functionality

• Must support filtering functions in IP and at the
  application level
• Must support that applications are filtered based
  on checksum

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Method 3 cont.

• Mobile phone must support
• Socket interface
• Personal firewall is informed each time new
  socket is created
• Trusted applications, servers (sites) and IPs

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Conclusion

• I have found out that the need for personal
  firewall with its proposed functions in mobile
  phone is essential. Even if implementation can be
  difficult, it is better than no protection at all.