Transcript Beyond WAP

Beyond WAP
By Zhongyin J. Daye
Han-Chung Lee
Agenda
• Introduction
– WAP Protocol Stack
– Future Wireless Environment
– Problem Facing WAP
• Application Layer
• Transport Layer
• Conclusion
WAP Protocol Stack
• WAP has layer-to-layer
communication.
• Wireless Datagram
Protocol (WDP) runs on
top of different network
bearer.
• Wireless Transaction
Protocol operates on top of
WDP.
Future Wireless Environment
Platform
Networking
System
Cost per Base
Station
Cost per
Operator
CDPD
HSCSD
GPRS
EDGE
TDMA
GSM
GSM
GSM
Circuit Switched
Circuit Switched
Packet Switched
Packet Switched
$500-1000
$4000
$20,000
$70,000
IS-136+
TDMA
$20,000
IS-95B
1XRTT
CDMA
CDMA
Circuit/Packet
Switched
Packet Switched
Packet Switched
$3-6 million
$20-30 million
$50-120 million
$300-600
million
$50-120 million
W-CDMA
GSM/PD
C
TMDA
Packet Switched
N/A
Packet Switched
$70,000
CDMA
Packet Switched
N/A
IS-136HS/UWC136
CDMA2000
Generation
First
Second
2.5
Third
Attributes
Analog
Digital, 9.6kbps
Digital, 57.6-384kbps
Digital, 384kbps-2Mbps
Source: Merill Lynch, WAP Forum, & Beyond WAP Group
$20,000
$70,000
Maximum Data
Transmission
Rate
32kbps
57.6kbps
115kbps
384kbps
64kbps
$50-120 million
$300-600
million
N/A
64kbps
144kbps
$300-600
million
N/A
384kbps
Applications
Basic Voice
Advanced Voice, SMS
SMS, Internet
Video, Internet, Multimedia
2Mbps
144kbps
Problems Facing WAP
• WAP only support simple graphic and text
in one specific format and is not compatible
with the Internet.
• 3G wireless applications will be dominate
by streaming multimedia, which WAP does
not support.
Agenda
• Introduction
• Application Layer
–
–
–
–
iMode
Java (Accessory Application Support)
Mobile Markup Language (MML)
WAP 2.0
• Transport Layer
• Conclusion
iMode
Current Service Comparison:
Imode
cHTML
Packet switched
Colored gifs
Application and applet
downloads
WAP
WML
Circuit switched
Wireless (uncolored) bmp
Server-centric
application
NTT DoCoMo & Java Alliance
- enhanced security
- game downloads
- vector-driven client-generated graphics
Source: Eurotechnology Japan K. K., NTT DoCoMo, & Beyond WAP Group
Java
Java™ 2 Platform, Micro Edition (J2ME)
- allows dynamic download of new applications over wireless networks
- vector-driven client-generated graphics ensures viability of real-time games such
as Tetric and 3D Maze
K virtual Machine (KVM)
- provides highly optimized runtime environment for small hand-held devices
- offers multithreading and garbage collection
- compatible with Java 2 Platform, Standard Edition (J2SE) & Java 2 Platform,
Enterprise Edition (J2EE)
Mobile Information Device (MID) profile offers APIs facilitating user
interface, persistent storage, security and messaging on wireless devices.
Source: Sun Microsystems, Inc.
Java (Continued)
JavaPhone provides direct
telephony control, datagram
messaging, address book and
calendar information, user profile
access, power monitoring, and
application installation.
Source: Sun Microsystems, Inc.
Mobile Markup Language(MML)
Subset Principle: uses different application environment package for different
devices
S-MML
12 letters by 4
lines display
No Images
Tables not
indicated
M-MML
¼ VGA display
Full MML
PC display
Images support
Tables not indicated
Images support
Tables
indicated
Source: MOBIDY & Beyond WAP Group
MML (Continued)
MML is built chiefly upon the
SMS system, but is also
applicable to both the packet
and circuit switch platform
Source: MOBIDY & Beyond WAP Group
MML (Continued)
MML’s Advantage over WAP
A. Support of HTML 4.0:
guarantees HTML convergence
later on.
B. Subset Concept: Allows
device differentiation while
maintaining same language
support
Source: MOBIDY, J-Phone, & Beyond WAP Group
WAP 2.0
•WAP envisions the
convergence of WAP
and XHTML.
•XHTML is the next
generation HTML that
seeks to separate
content from
transmission.
Source: Phone.com, Lehman Brothers, & Beyond WAP group
Agenda
• Introduction
• Application Layer
• Transport Layer
–
–
–
–
–
WAP Transport Layer
Alternative Transport Protocols
ESRO, VMTP, and MNCP
TCP
Suggestion on Transport Layer
• Conclusion
WAP Transport Layer
• WDP is replaced by UDP when the
underlying network bearer is IP.
• WTP is built on top of a datagram service.
• WTP is transactional based.
• WTP has no congestion control.
Alternative Transport Protocols
ESRO, VMTP, and MNCP
• Both ESRO and VMTP are transactionbased protocol built for RPC.
• WDP used ESRO and T/TCP as its design
model.
• MNCP is another proxy service similar to
WAP.
TCP
• TCP has too much overhead for wireless
links.
• TCP assumes all packet loss is due to
congestion.
• TCP does not provide layer to layer
communication.
Suggestion on Transport Layer
• Use TCP for streaming applications and
keep WTP for transactional applications.
• Improve TCP overhead by using Delayed
Dupack and SACK.
• Implement layer-to-layer communication in
TCP as an option.
• Adjust TCP window size to fit high latency,
high bandwidth wireless links.
Conclusion
• Application Layer
– WAP, iMode, & MML will coexist
– WAP will dominate within the next few years
due to its multi-bearer support
– iMode will dominate afterwards with its
unmatchable function supports
• Transport Layer
– Transport Layer converges to TCP.