Personal Server Model for Real-Space Networking

Shirou WAKAYAMA shirou@sfc.keio.ac.jp

KEIO University Japan.

Motivation

Attain Computing Environment using information in Real-Space Active Bat (Location-aware system using RF) GUIDE(Location-aware system using Wireless LAN) Oxygen(Location-sensing and using embedded

computers around the user)

Can not utilize various sensors in each system → Limited system availability and sensor

variationWe want to use various sensors in more Wide-

area

Sample Applications

Autonomous information obtainment current location name of the person standing before the

user

Autonomous health-care support Call ambulance automatically, when

user’s physical condition change suddenly

Autonomous diary generation Log user’s daily activity automatically

Assumed Environment

Pervasive/Ubiquitous Computing environment Users can be unaware of computers and devices Surrounding environment should care Centralization to Distribution!

Users move in wide-area Outside of lab, campus, town, everywhere

Various public sensors are setup everywhere Sensors differ depending on places Sensors nearby user will sense and inform The Internet is used to connect sensors each other

Problem statement

Sensor information Management Modelis required

No common interfaces between each research/sensors Each research has own Sensor information

managers and models No work has done to provide

interoperability

No model to make use of various sensors while moving anywhere No overarching model

Model Requirements

Sensor information be obtained anywhere Location Independent

Various sensor-devices be utilized Sensor-type Independent

Information be shared between people requested Only authorized people could request

Existing model consideration

1. Aggregate/Manage all sensor information to one Central Server

Less scalability

2. Manage sensor information by servers corresponding to each sensor

As users move, surrounding sensors will change accordingly

Other users may not know where to request sensor information of specific user

Personal Server Model(1/2)Manage Sensor information by servers corresponding to each user Manager can be set anywhere on the

Internet Manager can aggregate/manage

information from various sensors bound to each user

Other users can request sensor information by user specifiedLocation/Sensor-type Independency

in Pervasive Computing environment provided

Personal Server Model(2/2)

B

Real-Space

Virtual-Space Personal Server= Sensor information manager

Globally Unique ID‘GUID’

A

A B C

C

MiddleSensor Layer

Sensors

Experimentation

Experimentation 2002 Sep. , with 274 people , 4days 3night In the WIDE Project meeting

Sensor information Location-information from RF-ID and IP address Temperature information of electric hot-water

pot

Information service via Web interface Locate a person List people in a room specified Temperature information of pot

PSPS

System overview

HTTPD PS

A

B

PS = Personal Server

OtherApplication

HTTP

SQL

RF-ID IP AddressPot

Users

Location Sensing by RF-ID

RF-tag Sensor

Send Sensor Information to Personal Server of GUID ownerTo Personal

Server

Antenna

Ethernet

RS-232C

AntennaCable

Sensor device(1/3)

RFBase Stations

All User had RF-tag, that

Send GUID through RF.

RF Base Station

Coverage

Sensing by IP Address

IP address for location sensing IPv6 segment(prefix) differ per room DB has binding of prefix and room

name

Location information of Note PC per roomcan be provided

Sensor device(2/3)

Pot　 (Temperature Information)

Micro Node

Temperature Sensor

Sensor Device(3/3)

Locating a personService(1/2)

Locate your friend

Find out from GUID

Find out from NameFind out from

Organization

Listing people in a room specified

Click the room,

List people

Service(2/2)

Sensed Movement

BOF1BOF2BOF3

LOBBY1LOBBY2LOBBY3LOBBY4

PLENARY1PLENARY2

NOC

Actual Movement

Sensed Movement

0:00 12:00 24:00

Location Informationfrom RF-ID and IP addr.

BOF1BOF2BOF3

LOBBY1LOBBY2LOBBY3LOBBY4

PLENARY1PLENARY2

NOC

0:00 12:00 24:00

IP addrRFID

DivideOne large room

to Two

Future Work

Test scalability of Personal Server Model Not evaluated about Scalability with large

number of Personal Servers and users Not evaluated about Scalability of

mechanism that resolves IP address of Personal Server from GUID

Privacy Protection Secure communication between Sensor

and Personal Server Secure user authentication

ConclusionPersonal Server Model Personal Server manage sensor information per user

Personal Server Model realizes Location independency Sensor-type independency Pervasive Computing environment Sharing information between people

Experimentation Multiple sensor devices used for information

acquisition Web interface used

Personal Server Model can apply to the everyday use