Transcript What is mobility?

COM594: Mobile Technology
Lecture Week 1
Introduction to Mobility
2
What is mobility?
Moving, in
motion
Migrating,
changing
location
Immobile
Mobile
Changing
roles
1.3
Highway Scenario
GSM, 3G, WLAN,
Bluetooth, ...
PDA, laptop, cellular phones,
GPS, sensors
Mobility Market
Growth in Mobile versus Fixed Broadband Subscribers
The Internet is not Mobile..!
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Unfortunately the Internet does not support ‘native-mobility’
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The TCP/IP stack was not designed with mobility in mind.
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Much has been achieved, but the approach has been by the
development of ‘Tunneling Protocols’
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Tunneling means essentially using existing IP packets as
‘wrappers’, and running everything over the existing structure.
The Internet is not Mobile..!
•
However, we shall see that seamless, real-time mobility requires that
‘sessions stay alive’ when devices move between different types of
access networks and across networks belonging to different
operators.
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What is required is the capability to implement what has become
known as ‘Session-mobility’.
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This is a very tough challenge;
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However, if it can be achieved, the potential benefits for
communications is enormous.
The Internet is not Mobile..!
•
To understand the problem we need a detailed understanding of
the way that the Internet works.
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We need to appreciate the limitations of current Mobility ‘solutions’;
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Then we can begin to consider new approaches to building a truly
‘Mobile Internet’
The Future of Mobile Markets
 Device Divergence
 Network Convergence with cellular transition to “all-IP”?
 IP Everywhere
 Fixed and Cellular (Mobile) Networks: IP is the ‘fundamental
Building Block’
Wireless Residential
Gateway
(Access Point)
WiFi
Enabled
Tablet
Convergence between fixed and
cellular networks
DSLAM
Broadband
Network
Gateway
IP/Ethernet
Transport
Network
Home
ENB
Internet
DSLAM (Digital Subscriber
Line Access Multiplexer)
ENB (Enhanced Node B)
Cellular
Smartphone
Macro
ENB
Packet Data
Network/
Serving
Gateway
Correspondent
Node
Towards an ‘Always-On’ scenario:
Current cellular network standards allow mobile data-enabled devices
to Be attached to a cellular network without allocating them an IP
address.
Legacy cellular networks are typically configured to automatically deallocate a device’s IP address after a period of inactivity.
The new generation of cellular standards are designed only to
support always-on behaviour, and so, for example, when a device
attaches to an all-IP LTE network, it must, by default, receive an IP
address and be automatically enabled to send and receive IP
packets.