IEEE 802'11 Standards Comparison

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IEEE 802.11 Standards Comparison

• Mobile learning with ScholionWB
• Stadlhuber Gregor
• Wind Markus

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Subject area IEEE 802.11 Standard Comparison

• Diverse cable-free technologies
• Bluetooth
• Infrared
• GSM Technologies
• Wireless LAN
• Increased flexibility than terrestric networks
• Mobility achieves more importance daily
• i.e. public hot spots, meetings,...
• Various types of wireless network topologies
• Ad-Hoc
• Infrastructure Basic Service Sets
• Extended Basic Service Sets
• Wireless bridges
• Temporary and fixed networks

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Subject area IEEE 802.11 Standard Comparison

• Different standard specifications
• 802.11, 802.11a, 802.11b, 802.11g, 802.11h
• Region
• Rate
• Wave band
• Enhanced alogithms
• i.e. Frequency hopping
• Security
• Wired Equivalence Privacy (WEP)
• Shared meduim
• No guarantee of security

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Platform-specific content representation
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Level of detail senses

• Different knowledge representation
• Level of detail 1
• Presentation-like content overview
• Repeating already learned content
• Sample presentation
• Including illustrating content
• Level of detail 2
• Main learning core
• Book-like content representation
• Detailed information
• Including illustrating content
• Level of detail 3
• Virtual quiz game
• Knowledge check
• Knowledge rating
• Fun factor

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Platform-specific implementation

• Level of detail 1
• Textual content is shown on all platforms equally
• Rich representation on a PC
• Medium rich representation on a PDA
• Simplified pictures
• Omitting very detailed pictures
• Limited representation on Mobile Phones
• i.e. Omitting some pictures
• Level of detail 2
• Rich representation on a PC
• Medium rich representation on a PDA
• Each paragraph is displayed on a new screen
• Feeling of success
• Mobile phone screen resolution too little

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Platform-specific implementation

• Level of detail 3
• Virtual quiz game
• Displaying question and possible answers
• Showing answers on request
• Rating of right answers
• Suggested implementation technologies
• PC and PDA
• JavaScript
• Supported by the most common browsers
• IExplorer, Mozilla, Web Browser
• Mobile phone
• No wide-spread JavaScript support
• Use of XLink
• No rating mechanism includable

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Design considerations

• Blocks to avoid continuous text
• Text formatting options in Scholion
• Chapter path
• Headlines on a mobile phone
• Separated files for the different LODs
• Table of contents and linking of the document
• Chapter names in the tree

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Blocks to avoid continuous text
The intensive and structured usage of blocks
prevents continuous texts and makes the document
more comfortable to read.
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Text formatting options

• The Scholion tags allow only little formatting
• The tags have semantic meanings, this could cause
  problems
• Classic options like font sizes or bold texts are
  desirable
• Elements like line feeds or blank lines would
  improve the layout

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Title and path
The title of the current content (Phone) and the
shown path of the current page (PDA and Phone)
point to the actual position within a learning
unit.
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Separate units for the LODs
If both LODs are combined in one learning unit,
the one that was not rendered is displayed in the
tree as well. Furthermore the blocks of this LOD
are shown with their headers only.
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Navigating

• Navigating strategy is essential for keeping the
  overview in Level of Detail 2
• PC media
• Tree view
• PDA media
• Directory required
• Directory entries link to the content pages
• Each content pages includes a return link to the
  directory
• Links implemented with XLink
• Page numbers
• On LOD2 for PDA and mobile phone essential
• Enhances overview ? motivation enhancement

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Navigating

• Concerns all LODs on rendering level 1
• Length of tree elements is limited strongly
• Decreases transparency in navigation
• Especially with page numbers at the line end
• Strengthens the wish for page numbers directly on
  each content page