Thomas Kunz
Systems and Computer Engineering
18
WWW for Mobile Devices
nApplication gateways, enhanced servers
–simple
clients, pre-calculations in the fixed network
–compression,
filtering, content extraction
–automatic
adaptation to network characteristics
nExamples
–picture
scaling, color reduction, transformation of the document format (e.g., PS to TXT)
–detail
studies, clipping, zoom
–headline
extraction, automatic abstract generation
–HDML
(handheld device markup language): simple language similar to HTML requiring a special browser
–HDTP
(handheld device transport protocol): transport protocol for HDML, developed by Unwired Planet
nProblems
–proprietary
approaches, require special enhancements for browsers
–heterogeneous
devices make approaches more complicated