s15 - computer science and engineering department, iit kanpur
TRANSCRIPT
Wireless Technology
Computing and communication evolution
Communication
Computing
Single User OS
Batchprocessingsystems
Timesharing WorkstationLANs
Internet
2G 3G
80s 90s 2000
1GMobileTelephony
Laptop users
Telephony
Millions
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
1,400
1,200
1,000
800
600
400
200
0
Mobile Internet Outlook
More handsets than PCs connected to the Internet not
too far in the future!
Projectedcellularsubscribers(Nokia 1999)
Projected PCsconnected tothe Internet(Dataquest 10/98)
Projected Webhandsets(Nokia 1999)
* Source: Nokia presentation at IAB workshop 2000
What makes mobile computing different ?
Telephony
Computing
Single User OS
Batchprocessingsystems
Timesharing WorkstationLANs
Internet
1G 2G 3G
80s 90s 2000
MobileTelephony
Laptop users
Mobility Wireless Battery power3 fundamental differences
Mobility
Mobility: Requirements
Auto configuration Secure Remote access from anywhere anytime Access to information resources (web) E-mail, Notification Access continuity
The technical problem
3 key concepts name address routing
home network
M
foreign network
directoryservice
name
address
name to address mappingis dynamic
M
Two possible solutions
Update name to address mapping
home network
Mforeign network
directoryservice
M
Fix the routing layer
name ->new address
new address
Developments: 1992- 2002
DHCP
Dynamic DNS
PPP
Web
POP/IMAP
NAT/Firewalls
New developments
IP address == name Adaptive applications
graceful adaptation to network disruptions access from anywhere
Focus has shifted from device mobility to user mobility single user and multiple devices
New applications are emerging location aware context aware
X
Mobile user requirements
Auto configuration
Remote access
Web access
E-mail, notification
Anytime anywhere yes
Access continuity ?
What makes mobile computing different ?
Telephony
Computing
Single User OS
Batchprocessingsystems
Timesharing WorkstationLANs
Internet
1G 2G 3G
80s 90s 2000
MobileTelephony
Laptop users
Mobility Wireless Battery power3 fundamental differences
Wireless
Cellular data rates - hype and reality!
> 600 171.2 kbit/s + V.42 Bis CompressionEncrypted and already compressed data (images) do not compress
171.2 8 Timeslots x 21,4 kbit/s, CS-4 This is theorethical maximum for carrier capacity
149.8 7 Timeslots x 21.4 kbit/s, CS-4 1 timeslot reserved for signalling
115.2 8 Timeslots x 14,4 kbit/s, CS-2 First network implementations support CS-1 and CS-2
100.8 7 Timeslots x 14.4 kbit/s, CS-2 1 timeslot reserved for signalling
43.2 3+1 Timeslot mobile, CS-2First terminal implementations will be at most 3+1 (3 downlink TSs, 1 uplink). Uplink data rate 14,4 kbit/s
34.6 -20 % protocol overhead Assumed 80-20 payload-protocol ratio
31.1 -10 % retransmissions Retransmission rate depends on carrier quality
10-30 Simulations Simulation results for user data rate
kbit/sHow calculated Comments
Note: Radio path is a shared media: Carrier capacity Data rate seen by individual user6
/19
99
* Source: Nokia presentation at IAB workshop 2000
Bandwidth management issues
More efficient use of the link Application specific compression Compression methods must be able to cope with the growth of applications
Coping with extremely high level of contention QoS differentiation and pricing
corenetwork
What makes mobile computing different ?
Telephony
Computing
Single User OS
Batchprocessingsystems
Timesharing WorkstationLANs
Internet
1G 2G 3G
80s 90s 2000
MobileTelephony
Laptop users
Mobility Wireless Battery power3 fundamental differences
Cellular telephony: current picture
ANSI-41 core
IS-95
Europe North America
GPRS
CDPD
GSM core
GSM AMPSIS-136
ANSI-41 core
TDMA200 KHz
TDMA30 KHz
CDMA1.25 MHz
What is 3G ?
Higher rate 114 Kbps or higher in vehicular traffic 384 kbps for pedestrian traffic 2 Mbps or higher for indoor communication Variable rate traffic
Interoperability/roaming Geographic position determination capability
3G vision
AMPSIS-136
ANSI-41 core
IS-95
Europe North America
CDPD
WC
DM
A
UMTS core
GPRS
GSM core
GSM
5 MHz
3G reality
ANSI-41 core
AMPSIS-136
ANSI-41 core
IS-95
Europe North America
CDPD
WC
DM
A
UMTS core
GE
RA
N
CD
MA
2000
EvolvedIS-41 core
3G.PP 3G.PP2
HD
R
GPRS
GSM core
GSM
5 MHz 200 KHz
1.25 MHz
3G participants
IMT-2000
ETSI
3G.PP
Consortium &Partnerships
StandardsDevelopment Organizations
3G.PP2
T1
TTC (J)
TTA (K)
TIA
ARIB (J)
CWTS (c)
3G: the bigger picture
3G.IP MWIF
Mobile IP (macro mobility)
SeaMoby (micro mobility)
WC
DM
A
UMTS core
GE
RA
N
CD
MA
2000
EvolvedIS-41 core
3G.PP 3G.PP2
HD
R
What makes mobile computing different ?
Telephony
Computing
Single User OS
Batchprocessingsystems
Timesharing WorkstationLANs
Internet
1G 2G 3G
80s 90s 2000
MobileTelephony
Laptop users
Mobility Wireless Battery power3 fundamental differences
Battery power