Embed Size (px)
Citation preview
A Survey of Application Protocols for Wireless Devices
Éric Lesage
2000-12-04 Éric Lesage 2
Introduction
• SMS
• HDML
• I-mode
• WAP
• LEAP
• Summary
• Conclusion
2000-12-04 Éric Lesage 3
SMS (Short Message Service)
• Used to send messages from one device to another
• Gateways from and to Internet e-mail
• Very popular, particularly in Europe
2000-12-04 Éric Lesage 4
HDML (Handheld Device Markup Language)
<HDML version="3.0" markable="true">
<CHOICE name="main" key="pgtarg">
<ACTION type="accept" task="go" dest="/redirs_hd3.hdml?pgtarg=$(pgtarg)"><ACTION TYPE="SOFT1" LABEL="ABOUT" task=gosub dest="/hd3/about.hdml"><ACTION TYPE="help" task=gosub dest="/hd3/help.hdml?help=index"><LINE>INFOSPACE<ce task="go" dest="/hd3/my.hdml?&r=25569" REL=NEXT>My InfoSpace<CE task="go" dest="#direc">Directories<CE value="invi">Finance <CE value="spti">Sports<CE value="funst">Entertainment <CE value="nwsi">News<CE value="weat">Weather <CE value="ylwdir">Directions</CHOICE><CHOICE name="direc" key="pgtarg"><ACTION type="accept" task="go" dest="/redirs_hd3.hdml?pgtarg=$(pgtarg)"><ACTION label="DONE" type="soft1" task="go" dest="#main"><WRAP>DIRECTORIES<CE value="ppli">White Pages <CE value="ylwi">Yellow Pages<CE value="pplrl">Reverse Lookup<CE task="go" dest="http://yp.infospace.com/hd3/yel/finders.hdml?yp_f=N&r=25569"> Finders</CHOICE></HDML>
2000-12-04 Éric Lesage 5
I-mode
<html><head><META http-equiv="Content-Type" content="text/html; charset=x-sjis"><META name="CHTML" content="yes"><META name="description" content="欧州､国際ﾋﾞｼﾞﾈｯｽ "><title>( ｶ ) ﾕｰﾛﾃｸﾉﾛｼﾞｰ </title></head><body bgcolor="#ffffff" text="#000000"><center> ﾕｰﾛﾃｸﾉﾛｼﾞｰ <br>eurotechnology<br></center><hr>● メニュー： <br><A HREF="http://eu-japan.com/i/index.html" accesskey="1">驪</A>欧州のページ <BR><A HREF="eurotechnologyj.html" accesskey="2">麗</A> 会社案内 <BR><A HREF="eurotechnologye.html" accesskey="3">黎</A>English<BR><hr><center><A href=mailto:@docomo.ne.jp?body=http://www.eurotechnology.com/i/index.html> 友達に紹介 </a><br> ©2000 ﾕｰﾛﾃｸﾉﾛｼﾞｰ<BR></center></body></html>
2000-12-04 Éric Lesage 6
WAP (Wireless Application Protocol)
• The most widely-known solution (but not the most widely used)
• Works on practically any bearer (including non-IP)
• Complete protocol stack (not just application level)
• Heavily criticized
2000-12-04 Éric Lesage 7
LEAP (Lightweight and Efficient Application Protocol)
• “Underdog effort”: unlike WAP, no massive corporative support
• Focus on messaging solutions• Works using a binary remote procedure call
protocol (ESRO: efficient short remote operation protocol)
• Using EMSD (Efficient Mail Submission and Delivery Protocol), sending a short message requires 3 transmission, instead of at least 9 using TCP and SMTP.
2000-12-04 Éric Lesage 8
LEAP Protocols
IP
UDP or equivalent
ESRO
EMSD EHTD …
Bearer
2000-12-04 Éric Lesage 9
Summary
i-mode WAP LEAP Specifies transfer method No (closed) Yes Yes Specifies content format Yes (cHTML) Yes (WML) No Compatible with HTML Yes No Unknown Compatible with XML No Yes Unknown Primary application Web Web Messaging Currently in use Yes Yes No Underlying protocol Unspecified Many IP and UDP Navigation model Hyperlinks Cards Unknown Scripting and application Java (future) WMLScript Unknown Openness of protocols Mostly closed Open (licensing
issues) Open
2000-12-04 Éric Lesage 10
Conclusions
• 3G (UMTS, GSM GPRS, etc.) networks are IP based; is the WAP proxy model still justified?
• WAP: XHTML and maybe TCP in next version… protocol stack slowly starting to erode.
• LEAP: good idea, but no real taker so far.• i-mode: based on HTML; future lies in XML;
however, much richer experience (video on 3G; Java games, etc.)
