Transcript Basic Operations of the SIP-Based Mobile Network

IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 56, NO. 6, NOV. 2007
Design and Implementation of a SIP-Based
Mobile and Vehicular Wireless Network
With Push Mechanism
Yu-Chee Tseng, Jen-Jee Chen, and Yu-Li Cheng
National Chiao Tung University, Taiwan
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Outline
• Introduction
• System Architecture and Motivation
• Basic Operations of the SIP-Based Mobile Network
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MH Joining the Mobile Network
Session Setup Procedure and CAC and RM Mechanisms
Handoff Procedure
MH Leaving the Mobile Network
• Proposed Push Mechanism
– Sleep Procedure
– Wake-Up Procedure
• Experimental Results and Comparison
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Our Prototype
Call Setup Time and Maximum Num ber of Supported Calls
Handoff Delay
Performance of the Push Mechanism
Comparison of Signaling Cost
• Conclusion
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Introduction
• Extensive research has focused on how to maintain the
global reachability of a device without interruption even when
it is moving around.
• However, these host mobility management schemes manage
the mobility and connectivity of mobile devices in an
individual manner.
• Supporting host mobility when users exhibit group mobility
causes significant costs.
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Introduction (cont.)
• MIPv6-NEMO
– IETF network mobility working
group
– “Network Mobility Basic Support
Protocol” RFC 3963
• SIP-NEMO
– C.-M. Huang, C.-H. Lee, and J.R. Zheng, “A novel SIP-based
route optimization for network
mobility,” IEEE J. Sel. Areas
Commun., vol. 24, no. 9, pp.
1682–1691, Sep. 2006.
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Introduction (cont.)
• Both MIPv6-NEMO and SIP-NEMO have
shortcomings
– Do not consider how to manage wireless resource.
– Incurs unnecessary charges and energy consumption for
the external wireless interfaces.
– For SIP-NEMO, additional servers are required.
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Introduction (cont.)
• SIP-based Mobile Network Gateway (SIP-NMG)
– The only component that required.
• No modification required to the end nodes.
– Support multiple external interfaces.
– When there is no Internet activity, the SIP-NMG
disconnect the wireless interfaces to save energy and cost.
– SIP session control feature is exploited and a push
mechanism is proposed.
• A push server is required.
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System Architecture and Motivation
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System Architecture and Motivation
(cont.)
• Design motivations
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Saving charges of Internet access
QoS guarantee
Push mechanism
An added service for public transportation operators
Backward compatibility
Reducing handoffs
Saving the power consumption of MHs
Decreasing the complexity of MHs
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Basic Operations of
the SIP-Based Mobile Network
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MH Joining the Mobile Network
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Session Setup Procedure and
CAC and RM Mechanisms
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Handoff Procedure
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MH Leaving the Mobile Network
• The MH may detect other networks and update its
contact information by sending a SIP REGISTER
message.
– If there is an ongoing session, it can be resumed by SIP
re-INVITE.
• Since the MH does not deregister with the SIP-MNG,
the allocated resource will never be released.
• The authors suggest setting a timer for each session
and integrating the SIP-MNG with the underlying
routing protocol in MANET
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Proposed Push Mechanism
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Sleep Procedure
SIP-MNG id, status,
MSISDN, and IP address
SIP URI, SIP-MNG id, and
registration expiration time
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Wake-up Procedure
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Session Transfer Process
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Experimental Results and
Comparison
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The Prototype
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SIP-NMG (IBM T42) is implemented over FC4
– iptables and libipq are used for NAT and SIP-ALG
– External wireless interfaces
• Nokia card (GSM) phone
• PHS WiWi Card MC-P300/P-Card MC-6550 and Huawei E612 WCDMA PCMCIA card
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Push server (ASUS note book) is implemented by C++ on Microsoft Windows XP
MHs are IBM X23 with ASUS WL-167G usb WLAN adapters
– OS: Windows XP
– SIP client: Windows messenger 5.1
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Call Setup Time and Maximum Number
of Support Calls
• IP phone  MH2
– Support calls by single interface with
acceptable quality,
i.e. <1% packet dropping rate.
• A GPRS interface cannot provide enough bandwidth to
support even one single voice call
– the GPRS downlink bandwidth is only 28.8 kb/s, and the uplink
bandwidth is even less
• Via cellular > via 802.11
– Internet PSTN cellular network  MANET
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Handoff Delay
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Performance of the Push Mechanism
• IP phone  MH2
• Call setup time consists of two major components:
short message transmission time
+ wireless interface reconnection time
• The call setup time is not short.
– This is why we design our push server to temporarily answer an
incoming call to keep the session alive, or the caller may hang up
before the call is established.
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Comparison of Signaling Cost
(when handoff)
• The offline case
– SIP-MNG has no SIP signaling cost
– MIPv6-NEMO has to track network signaling and update
with its HA (costHABU)
• The online case
– SIP-MNG  N x costSIP-reregistration + S x costSIP-reINVITE
• N is the # of MHs in the mboile network
• S is the # of sessions
– MIPv6-NEMO  costHABU + M x costBU
• M is the # of CNs
• assume that the routing optimization approach based on binding
update for network prefixes is used
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Conclusion
• A SIP-based mobile network architecture to support
networking services on the roads
– Multiple wireless interfaces
– Dynamic bandwidth to internal users
– By interpreting SIP signaling, the RM and CAC
mechanisms inside the SIP-MNG can guarantee QoS for
users
– a push mechanism to allow the SIP-MNG to stay offline
– do not modify the current SIP client–server architecture
and protocol
• A prototype has been developed
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comments
• Simple, but maybe effective proposal
• The handoff detection on SIP-NMG still rely on lower
layer.
– May not be efficient enough
• When basing on Mobile IP(v6), if address translation
is used, the cooperation with upper (application)
layer should be considered.
– e.g., Using SIP.
• Implementing a prototype is interesting but requires
manpower and time.
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