Transcript Application Layer Mo..

Application Layer Mobility
Management Scheme
for Wireless Internet
Mohamed Elkanzi
Contents
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Introduction
3G IP Architecture
Mobility Management
Wireless IP Hand-off
Registration
Configuration & Dynamic Address Binding
Proposed Tier
Experiments
Conclusions
Introduction
• As the number of wireless devices connecting to
the internet is increasing, more work needs to be
done to standardize the all the IP wireless
networks.
• IETF, 3GPP and MWIF
• The focus is to merge the wireless and the wireline
networks.
• MIP provides some solutions but creates some
problems too.
• SIP as an alternative for MIP
3G IP Architecture
Domain Control
Agent
Domain Control
Agent
Regional IP Net
Internet
Radio Access
Network (RAN)
Regional IP Net
Radio Access
Network (RAN)
Mobility Management
• Mobility management requirements:
– Availability
– Global roaming
– Supports real time (telephony) and non-realtime (mobile web access) services.
– Supports TCP applications
– Supports multicast connections
– Handles registration, configuration, dynamic
binding, and location management
Wireless IP Hand-off
• The procedure is divided into three logical
layers:
– Cell hand-off
– Subnet hand-off
– Domain hand-off
Registration
• Newly joining MS sends registration
• The network performs:
– Accounting
– Authorization
– Auditing
• When a MS moves between subnets
appropriate registration is carried out by
intermediate servers or SIP agents.
Configuration & Dynamic Address
Binding
• As MS changes networks it requests a new
IP and the network’s subnet information
• The DNS should be updated automatically
• Dynamic Address Binding is for an MS to
maintain an address during its session no
matter which network it belongs to.
• Location management is maintained and
updated frequently
Proposed Tier: Terminal Mobility
• Multimedia traffic is categorized as realtime
and non-realtime by loss and delay factors.
• Different protocols are used to transport the
categorized traffic.
• RTP/UDP is for realtime traffic
• TCP is for non-realtime traffic
Terminal Mobility for Real-Time
application
• For real-time applications delay and loss are
the major concern
• Triangular routing and packet
encapsulation should be avoided
• Hand-off must be efficient
• SIP is used to support subnet and domain
handoff, while cell hand-off is taken care by
the link layer
Non-real-time Applications
• SIP signaling is used to transport TCP
packets.
• Each MS has a SIP agent that maintains its
TCP connections
• The agent also maintains the MS’s original
and current IP addresses.
Service & Personal Mobility
• This aspect assures that the user is able to
maintain and obtain services.
• The server’s ability to control the user’s
sessions and services. These properties
could be transferred during hand-off and
SIP registration
• SIP’s URI provides the user with the ability
to make use of the services anywhere
anytime.
Test-bed
Experiments
• Customized version of University
Columbia’s SIP client sipc and SIP server
sipd
• Two clients over IEEE 802.11 environment
• A lighter DHCP version was used DRCP
Conclusions
• The proposed architecture provides an
alternative for a wireless internet enabled
services
• SIP provides a flexible protocol to maintain
and obtain services while being mobile.