Upload
joseph-dsouza
View
222
Download
0
Embed Size (px)
Citation preview
8/10/2019 Intro Mobilecomputing
1/46
Introduction to MobileComputing
CEN 5531
Sumi Helal, Ph.D.Associate Professor
Computer & Information Science & Engineering Department
University of Florida, Gainesville, FL 32611
Phone: (352) 392-6845
8/10/2019 Intro Mobilecomputing
2/46
Fantastic BreakthroughTechnology
Wireless communication networks multiple networks covering the globe wold-wide deregulation and spectrum auctions
standard communication systems and air link
interfaces Portable information appliances
laptops, notebooks, sub-notebooks, and MNCs
hand-held computers
PDAs and smart phones
Internet: TCP/IP& de-facto application protocols
ubiquitous web content
8/10/2019 Intro Mobilecomputing
3/46
New Forms of Computing
Wireless Computing Nomadic Computing
Mobile Computing
Ubiquitous Computing
Pervasive Computing
Invisible Computing Metamorphic Computing
Distributed
Computing
(Client/Server)
8/10/2019 Intro Mobilecomputing
4/46
8/10/2019 Intro Mobilecomputing
5/46
Nomadic, Mobile & Ubiquitous
No
Network
Mobile ComputingNomadic Computing
Wireless
Network
(B)
Fixed
Network
Wireless
Network
(A)
FixedWireless
Network
Ubiquitous Computing
8/10/2019 Intro Mobilecomputing
6/46
Another View of UbiquitousComputing
Mark Weisers views
http://www.ubiq.com/hypertext/weiser/UbiHome.html
8/10/2019 Intro Mobilecomputing
7/46
Impressive WirelessInfrastructure!
Satellite
Macro-CellMicro-Cell
Urban
In-Building
Pico-Cell
Global
Suburban
In-Room
(BlueTooth)
8/10/2019 Intro Mobilecomputing
8/46
Wireless Communication
Technology
(IMT-2000)
8/10/2019 Intro Mobilecomputing
9/46
GSM Base Stations in Europe
Nokia PrimeSite
Ericsson RBS 2000
8/10/2019 Intro Mobilecomputing
10/46
Wireless Network Overlay
Satellite
Macro-Cell
Micro-Cell
Urban
In-Building
Pico-Cell
Global
Suburban
8/10/2019 Intro Mobilecomputing
11/46
Wireless Network Convergence2G/3G Mobility-Bandwidth Trade-off
Mobility
Bandwidth
10K 100K 1M 10M 100M 1G
Room
Global GSM
D-AMPS/IS-95
DECTDECT
DECT
WLAN
UMTSNational
Regional
Metropolitan
Campus
Office
1-7 GHz
0.1-2 GHz
0.1-2.3 GHz
2-4 GHz
2-7 GHz
>2 GHz
20-50 GHz
8/10/2019 Intro Mobilecomputing
12/46
UMTS: Universal Mobile Telecomm.Standard
Global seamless operation in multi-cell
environment (SAT, macro, micro, pico) Global roaming: multi-mode, multi-band,
low-cost terminal, portable services & QoS
High data rates at different mobile speeds:144kbps at vehicular speed (80km/h), 384kbps at pedestrian speed, and 2Mbps indoor(office/home)
Multimedia interface to the internet
Based on core GSM, conforms to IMT-2000. Deployment as early as 2002.
UMTS
ETSI
SMG
ITU
IMT-2000FPLMTS
IMT
8/10/2019 Intro Mobilecomputing
13/46
Motorola Marco
8/10/2019 Intro Mobilecomputing
14/46
Motorola Envoy
8/10/2019 Intro Mobilecomputing
15/46
The Palm
8/10/2019 Intro Mobilecomputing
16/46
The Pocket PC
8/10/2019 Intro Mobilecomputing
17/46
The Nokia 9000 Communicator
8/10/2019 Intro Mobilecomputing
18/46
The Sharp Zaurus
8/10/2019 Intro Mobilecomputing
19/46
The Vadem Clio
8/10/2019 Intro Mobilecomputing
20/46
Fujitsu Stylistic 2300/3400
8/10/2019 Intro Mobilecomputing
21/46
Sub-Notebook
8/10/2019 Intro Mobilecomputing
22/46
Notebook
8/10/2019 Intro Mobilecomputing
23/46
The First Wrist PC: Ruputer
8/10/2019 Intro Mobilecomputing
24/46
Japans PHS Phone, Year 2001
8/10/2019 Intro Mobilecomputing
25/46
8/10/2019 Intro Mobilecomputing
26/46
8/10/2019 Intro Mobilecomputing
27/46
8/10/2019 Intro Mobilecomputing
28/46
The Power Ring
8/10/2019 Intro Mobilecomputing
29/46
NTT Key Fingers
8/10/2019 Intro Mobilecomputing
30/46
The Projection Keyboard
http://www.canesta.com
8/10/2019 Intro Mobilecomputing
31/46
Portable Information Appliances
Subscriber Identification
Module (SIM)
Car Stereo-Phone
8/10/2019 Intro Mobilecomputing
32/46
Beneficiaries of Ubiquitous
Computing
Commuters
Travelers
Stock traders
Medical
Law enforcement
Package delivery
Education
Insurance
Emergency
Trucking
Intelligence Military
Clients
Adhoc network
Servers
Intranet
Internet
8/10/2019 Intro Mobilecomputing
33/46
Limitations of the MobileEnvironment
Limitations of the Wireless Network heterogeneity of fragmented networks
frequent disconnections
limited communication bandwidth
Limitations Imposed by Mobility
Limitations of the Mobile Computer
8/10/2019 Intro Mobilecomputing
34/46
Frequent Disconnections
Handoff blank out (>1ms for most cellulars) Drained battery disconnection
Battery recharge down time
Voluntary disconnection (turned off to
preserve battery power, also off overnight)
Theft and damage (hostile environment)
Roam-off disconnections
8/10/2019 Intro Mobilecomputing
35/46
Limited CommunicationBandwidth
Orders of magnitude slower than fixed network Higher transmission bit error rates (BER)
Uncontrolled cell population
Difficult to ensure Quality of Service (QoS)
Asymmetric duplex bandwidth
Limited communication bandwidth exacerbatesthe limitation of battery lifetime.
8/10/2019 Intro Mobilecomputing
36/46
8/10/2019 Intro Mobilecomputing
37/46
Caesar and Brutus
8/10/2019 Intro Mobilecomputing
38/46
Limitations Imposed by Mobility
Lack of mobility-awareness by applications
inherently transparent programming model (object-,components-oriented, but not aspect-oriented)
lack of environment test and set API support
Lack of mobility-awareness by the system network: existing transport protocols are inefficient to use across
heterogeneous mix of fixed/wireless networks
session and presentation: inappropriate for the wireless
environment and for mobility operating systems: lack of env. related conditions and signals
client/server: unless changed, inappropriate and inefficient
8/10/2019 Intro Mobilecomputing
39/46
Research Roadmap
Wireless: MAC + Air Link Protocol
Mobile: DHCP,Mobile IP, Ad-Hoc Routing
Transport: Optimized TCP
OS Services: Loc. Sensitive
Naming, File Systems, others
Mobile
Computing Models
Transactions
Apps
8/10/2019 Intro Mobilecomputing
40/46
Mobile and Wireless
Networking Issues
Mobile IP
Wireless Transport
Ad-Hoc Networks
Location Management
Wireless Network Benchmarking
Ad-Hoc Network Simulation Wireless Link Simulation
8/10/2019 Intro Mobilecomputing
41/46
8/10/2019 Intro Mobilecomputing
42/46
Mobile file and DatabaseSystems
Wireless File System Access Disconnected File Systems
Mobile Access to C/S or Distributed Databases
Ad-Hoc Database Systems Checkpointing
Database recovery
Mobile Database Deisgn
8/10/2019 Intro Mobilecomputing
43/46
Mobile Transaction andWorkflow
ACID Relaxation Mobile Transaction Models
Optimistic Data Replication
Semantic-based Conflict Resolution
Consensus in Mobile Environment
8/10/2019 Intro Mobilecomputing
44/46
Wireless and MobileApplications and Services
Application Design for Wireless networks
Application Design for Mobility
Wireless WWW Access
Active Badges (Teleporting)
Wireless Classroom (Wireless Campus!)
Mobile Groupware
Location-sensitive Yellow Service
Pervasive Computing and Smart spaces
. . . . .
8/10/2019 Intro Mobilecomputing
45/46
Performance and QoS
QoS Measures in Wireless and MobileEnvironments
QoS Guarantees
Simulators and Emulaors of Wireless Links
Simulators of Mobile and Ad-hoc Networks
Wireless Networking Benchmarking
8/10/2019 Intro Mobilecomputing
46/46
Emerging Standards
The 802.11b
The BlueTooth Standard
The Wireless Application Protocol (WAP)
The CompactHTML The Network Computer Reference Specification
Telecom Standards: UMTS