IMOBILE: A PROXYBASED PLATFORM FOR MOBILE SERVICES

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IMOBILE A PROXY-BASED PLATFORM FOR MOBILE
SERVICES

• Author Chung-Hwa Herman Rao, Yih-Farn Robin
  Chen, Di-Fa Chang and Ming-Feng Chen
• NETWORK SERVICES RESEARCH CENTER, ATT LABS
• Presented by Pengpeng Lu

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OUTLINE

• OBJECTIVE
• INTRODUCTION
• ARCHITECTURE OF IMOBILE
• LET ENGINE AND USER/DEVICE PROFILES
• SUMMARY
• FUTURE WORK

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OBJECTIVE

• PROVIDE A PERSONAL AGENT ON THE NETWORK THAT
  ALLOWS MOBILE USERS TO ACCESS ALL SERVICES.
• - NO MATTER WHERE THEY ARE.
• - NO MATTER WHAT DEVICES.

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INTRODUCTION
DIFFERENT DEVICE AND PROTOCOLS DO NOT
COMMUNICATE EACH OTHER EASILY - Palm PDA
- Cell Phone - Email Devices -
Pocket PCs MOBILE USERS - DIFFERENT
NEEDS, MOTIVATION AND CAPABILITIES FROM
WIRELINE USERS - MULTI-TASKING MODE
- VERY TASK-ORIENTED
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INTRODUCTION
FIGURE 1. Accessing iMobile Services Through
Various Devices and Networks.
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ARCHITECTURE OF IMOBILE
FIGURE 2. Architecture of iMobile
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FIGURE 3. Architecture of iMobile
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DEVLET
A DEVLET PROVIDES A PROTOCOL INTERFACE TO A
DEVICE ON A PARTICULAR ACCESS NETWORK.
SUPPORT SMS protocol IMAP email protocol AIM
protocol ICQ protocol Telnet protocol WAP
protocol HTTP protocol
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DEVLET

• EACH DEVLET INTERACTS WITH THE LET ENGINE IN
• A STANDARD WAY
• RECEIVE EACH REQUEST AS A CHARACTER STREAM
• SEND THE CHARACTER STREAM, INTERPREDTED AS
• AN IMOBILE COMMAND AND ASSOCIATED
• PARAMETERS TO THE LET ENGINE
• RETURNS RESULTS IN A MIME TYPE ACCEPTABLE
• BY THE RECEIVING DEVICE (DETERMINED BY THE
• CORRESPONDING DEVICE PROFILE STORED AT THE
• LET ENGINE

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DEVLET
EACH COMMAND INVOKES AN APPLET THAT CORRESPONDS
TO A SERVICE WITH A SET OF SERVICE PARAMETERS

• EXAMPLES
• TO ACCESS THE STOCK PRICE OF ATT (T)
• quote T
• TO FORWARD THE RESULT TO herman_at_research.att.com
• forward mail herman_at_research.att.com quote T

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INFOLET
RETRIEVE OR WRITE TO AN INFORMATION SPACE
USING AN ACCESS PROTOCOL APPROPRIATE FOR THE
INFORMATION SOURCE AVAILABLE INFORMATION
SPACES - Stock quote, weather, flight
schedule, etc (Access websites) Example An
AIM client of YihFarn talks to an iMoible AIM
agent, issued the flight
008 command to get flight information on the
NorthWest airline and
received the concise output that includes time
and gate information of
each leg of the flight
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INFOLET

• Mapping from the flight command
• to the NorthWest airline
• Invoke necessary transcoding services
• to map to an appropriate format

FIGURE . Accessing Flight Info Through iMobile.
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INFOLET
INFORMATION SPACES (Continued) - Corporate
Database (Accessed through the JDBC and
ODBC interfaces) iMobile hosts a JDBC
infolet that allows mobile users to access
or update enterprise database information
(employee data, marketing/sales data, etc)
through SQL-like queries. -
Network/Infrastructure Resources (Accessed
through the CORBA interfaces)
iMobile hosts a CORBA infolet that allows mobile
users to request services from CORBA
objects.
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INFOLET
INFORMATION SPACES (Continued) - Mobile
Control of X10 Home Network Devices iMobile
hosts an X10 infolet that controls home network
devices connected to its server machine. -
Emailson Mail Servers iMobile supports and
IMAP infolet called inbox that can query and
view a users email account.
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APPLET
IMPLEMENT BUSINESS OR APPLICATION LOGIC BY
PROCESSING CONTENTS FROM DIFFERENT SOURCES AND
RELAYING RESULTS TO VARIOUS DESTINATION
DEVICES An Applet may simply sends a message
from one device to another without using any
information sources
OR Have complex interaction with other
infolets.
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LET ENGINE

• RECEIVE COMMANDS FROM DEVICES, TRANSLATE
• THE COMMANDS ACCORDING TO USER ALIASES AND
• PROFILES, AND THEN FORWARDS THE SERVICE
• REQUEST TO THE RIGHT APPLET OR INFOLET
• INVOKE THE APPROPRIATE TRANSCODING SERVICE
• TO CONVERT RESULTS RETRUNED FROM INFOLETS
• OR APPLETS TO A FORMAT APPROPRIATE FOR THE
• TARGET DEVICE
• ALL DEVLETS, INFOLETS, AND APPLETS MUST BE
• REGISTERED AT THE LET ENGINE FIRST BEFORE
• COMMUNICATIONS WITH OTHER AGENTS CAN
• OCCUR

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DEVICE PROFILE
EVERY DEVICE MUST REGISTER ITS PROFILE
INFORMATION WITH THE LET ENGINE FIRST DEVICE
NAME protocolacct_id A DEVICE PROFILE IS A
LIST OF ATTRIBUTE-VALUE PAIRS
dev.format.accept determine what MIME type the
device is
allowed to accept e.g. dev.format.acceptte
xt/plain dev.page.size230
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DEVICE PROFILE (CONTINUED)
EVERY DEVLET IS MODELED AS A SPECIAL DEVICE IT
REQUIRES MORE INFORMATION IN THE DEVICE PROFILE
TO TELL IMOBILE HOW AND WHEN TO ACCESS THIS
DEVICE. e.g. mail.store.checktime10000
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DEVICE to USER MAPPING
EACH DEVICE HAS TO BE MAPPED TO A REGISTERED
IMOBILE USER. REASONS - LIMITING ACCESS TO
LEGITIMATE IMOBILE USERS ONLY - PERSONALIZE
A SERVICE BASED ON THE USER PROFILE A typical
device-to-user map sms 886936731826herman
sms 19087376842chen maildchang_at_researc
h.att.comdifa aimwebciaochen
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USER PROFILE
A typical iMobile user profile nameRobin
Chen Passwordxf2gbH3
command aliases defaultmail.1
sms.cmd.qquote my
addresses
sms.cmd.snsitenews sms.1sms19087376842
address aliases mail.1mailchen_at_rese
arch.att.com sms.addr.ccaimchrischen mail.2m
ailimobile_at_mobile.att.net mail.allmail.1,
mail.2 aim.1aimwebciao
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• SUMMARY
• IMIBILE INTRODUCES THREE ABSTRACTIONS ON TOP OF
  AN AGNET-BASED PROXY
• DEVLET TO INTERACT WITH VARIOUS
• ACCESS DEVICES AND PROTOCOLS
• INFOLETS TO ACCESS MULTIPLLE
• INFORMATION SPACES
• APPLETS TO IMPLEMENT APPLICATION AND
• SERVICE LOGIC
• THE LET ENGINE ARBITRATES THE COMMUNICATIONS
  AMONG DEVLETS, APPLETS, AND INFOLETS, IT
  MAINTAINS USER AND DEVICE PROFILES, WHICH ARE
  USED TO PROVIDE PERSONALIZED SERVICES AND TO
  PERFORM TRANSCODING BEFORE RETURNING CONTENTS TO
  RECEIVING DEVICES.

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FUTURE WORK INTEGRATE IMOBILE WITH LOCATION
SERVICES TO FURTHER REDUCE THE PARAMETERS (ZIP
CODE, LONGITUDE, LATITUDE, ETC.) THAT A MOBILE
USER IS REQUIRED TO ENTER TO ACCESS USEFUL
INFORMATION EXPERIMENT WITH VOICE XML
TECHNOLOGOES TO PROVIDE A VOICE-BASED DEVLET FOR
INFORMATION RETRIEVALS