2. Mobile Computing
A simple definition could be: Mobile Computing is using a computer (of one
kind or another) while on the move
Another definition could be: Mobile Computing is when a work process is
moved from a normal fixed position to a more dynamic position
A third definition could be: Mobile Computing is when a work process is
carried out somewhere where it was not previously possible
Mobile Computing is an umbrella term used to describe technologies that
enable people to access services anytime and anywhere
3. Mobile Computing
Many other names/overlapping computing paradigms:
Pervasive Computing
Ubiquitous Computing
Wireless Systems
Internet of Things (IoT)
Embedded Computing
Nomadic Computing
Wireless Sensor Networks
(Mobile) Ad-Hoc Networks
Mesh Networks
Vehicular Networks
…
4. Mobile Computing
• Applications
• Location-awareness
• Mobility Support
• Security
• Resource Management
• Network Protocols
• Broadcast
• Technologies
• Standards
• Wireless Medium
Wireless Communication
Mobile Computing
5. Wired vs Wireless
Wired Networks
high bandwidth
low bandwidth variability
can listen on wire
high power machines
high resource machines
need physical access (security)
low delay
connected operation
Mobile Networks
low bandwidth
high bandwidth variability
hidden terminal problem
low power machines
low resource machines
need proximity
higher delay
disconnected operation
6. Why Go Mobile?
Enable anywhere/anytime connectivity
Bring computer communications to areas without pre-existing infrastructure
Enable mobility
Enable new applications
An exciting new research area
7. Evolution
Mobile computing can be categorized into seven major categories of focus
These categories are the basis for the technology that is used today in
research and design of mobile computing
Each category or section is a different area that was focused on making
mobile computing what it is today
These seven categories are: Portability, Miniaturization, Connectivity,
Convergence, Divergence, Apps, Digital Ecosystems
8. Portability
Reducing the size of hardware to enable the creation of computers that could
be physically moved around relatively easily
9. Miniaturization
Creating new and significantly smaller mobile form factors that allowed the
use of personal mobile devices while on the move
10. Connectivity
Developing devices and applications that allowed users to be online and
communicate via wireless data networks while on the move
11. Convergence
Integrating emerging types of digital mobile devices, such as Personal Digital
Assistants (PDAs), mobile phones, music players, cameras, games, etc., into
hybrid devices
12. Applications (Apps)
The latest wave of applications (apps) is about developing matter and
substance for use and consumption on mobile devices, and making access to
this fun or functional interactive application content easy and enjoyable
13. Mobile IP - Motivation
An IP address not only identifies a host but also a point-of-attachment
A host cannot change its IP address without terminating on-going sessions
Mobility is the ability of a node to change its point-of-attachment while
maintaining all existing communications and using the same IP address
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14. Mobile IP – The Gory Details
Mobile node can use 2 IP addresses
Static Home Address (identifies TCP connections)
Dynamic Care-of-Address (current point of attachment on the network)
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15. Mobile IP – Details (Contd.)
Mobile IP is a cooperation of 3 mechanisms
Discovering the care-of-address
Registering the care-of-address
Tunneling to the care-of-address
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16. Mobile IP – Details (Contd.)
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FA
FA Advertises Service
FA
FA
HA
Remote Redirect
17. Mobile IP – Details (Contd.)
Recap (Remote Redirect)
MH requests service from FA
FA relays request to HA
HA accepts the request (if possible) and its modifies routing table
FA relays this to ths MH
See anything missing?
Malicious node could cause HA to alter its routing table with erroneous COA
(DOS Attack?)
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18. Mobile IP – Details (Contd.)
Solution?
Digitally signed Remote Redirect (RR) messages
Would it work now?
What about replay attacks?
Solution?
RR messages could be made unique – How?
Timestamps with each message
Pseudorandom number with each message
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19. How will Mobile IP change with IPv6?
Stateless Address Autoconfiguration and Neighbor
Discovery precludes the need for Foreign Agents
Security
All IPv6 nodes implement strong authentication and
encryption features
Source Routing
Correspondent nodes no longer tunnel packets to MHs
Instead they use IPv6 routing headers (variation of IPv4
source routing option)
More …
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20. Ongoing Work and Open Questions
Routing inefficiencies
Triangle Routing
Security Issues
Ingress Filtering
Slow Growth in the Wireless LAN Market
Competition from other protocols
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