The wristwatch as a mobile ICT device...
Increasingly, we are seeing convergence of functionality - one device to do all. Yet the bundling can make the devices less reliable.
WiFi not a good networking technology because it has a very short range but it can be supplemented by cellular communication networks.
Telecommunications Protocols
Primary: 2G, 3G - GPRMS, UMTS, WiMAX etc - give roaming access that merges voice and IP access.
Secondary: WiFi - cheaper, faster, and more reliable but need to be close to repeater station.
GPS
24 statellites in medium Earth orbit (20,000 km altitude) arranged in 6 orbital planes, each with 4 satellites. Satellites broadcast time-stamped messages to calculate time-difference between sending and recieving. You can then calculate distances to satellite if you know the satellites position. GPS uses distance rather than direction.
Each added function brings new possibilities:
Mic+camera+environmental sensors = baby monitor.
You can add network connectivity to personal devices to make them interpersonal. Even off-line devices can store information to be up-loaded to network later.
Bad Things are Happening!
Loss/damage/theft - if you keep all your personal information on your handy-dandy mobile computing device and you lose it - you lose everything. Not only this but the person who finds it finds everything. This is clearly a huge wind-fall for the cyberstalkers but not so good for you. Unless, of course, you wish to be cyberstalked. Actually, it is a windfall for regular stalkers as well...
Showing posts with label Chris Edwards. Show all posts
Showing posts with label Chris Edwards. Show all posts
2.2.10
The Deep Web (Class 18) - Chris Edwards
How do we browse those things that are non-browsable.
Deep/Invisible/Hidden/Dark Web
Centres around the notion of searchability - it is not indexed by search engines so it is unlikely to be found.
So, how do we find things on the dark web? Traditional browsing, social bookmarking, word of mouth, blogs.
Libraries as analogy. They are highly organised and can be browsed or found via an OPAC. Closed-stack with no OPAC is of little use to the public. Each website is like a library - with "shallow web" - that is publicly accessible with advertised existence - and "deep web" - not open/known to public this does not mean concealed, but simply obscure.
Organisation leads to usability because structure enables automation. Web indexes create a highly organised structure external to the content - this makes finding your stuff much quicker.
Why is it Hidden?
Intentionally - may require log-in, reputation may be good without indexing of deep content, may be technically difficult to provide the data needed.
Accidentally - laziness, carelessness, indifference, lack of knowledge.
Data and Metadata
Increasing level of abstraction but this goes along with increasing utility. Adding good quality metadata means you can make your data more findable. Metadata are usually concise, precise, well-specified, and uniform across a variety of content. Web authors can provide their own metadata (self-cataloguing).
Complement any search facility with a browsing interface. Avoid JavaScript - bots don't like them. Keep URLs distinctive (URL should determine content). Flickr as both searchable and browsable.
HTML IMG element requires ALT attribute (improves accessibility to vision-impaired users and enables images to be indexed by keyword).
Remember: not only humans are looking at your site-love your robot friends! (Or Clamps will initiate the clampage...)
Deep/Invisible/Hidden/Dark Web
Centres around the notion of searchability - it is not indexed by search engines so it is unlikely to be found.
So, how do we find things on the dark web? Traditional browsing, social bookmarking, word of mouth, blogs.
Libraries as analogy. They are highly organised and can be browsed or found via an OPAC. Closed-stack with no OPAC is of little use to the public. Each website is like a library - with "shallow web" - that is publicly accessible with advertised existence - and "deep web" - not open/known to public this does not mean concealed, but simply obscure.
Organisation leads to usability because structure enables automation. Web indexes create a highly organised structure external to the content - this makes finding your stuff much quicker.
Why is it Hidden?
Intentionally - may require log-in, reputation may be good without indexing of deep content, may be technically difficult to provide the data needed.
Accidentally - laziness, carelessness, indifference, lack of knowledge.
Data and Metadata
Increasing level of abstraction but this goes along with increasing utility. Adding good quality metadata means you can make your data more findable. Metadata are usually concise, precise, well-specified, and uniform across a variety of content. Web authors can provide their own metadata (self-cataloguing).
Complement any search facility with a browsing interface. Avoid JavaScript - bots don't like them. Keep URLs distinctive (URL should determine content). Flickr as both searchable and browsable.
HTML IMG element requires ALT attribute (improves accessibility to vision-impaired users and enables images to be indexed by keyword).
Remember: not only humans are looking at your site-love your robot friends! (Or Clamps will initiate the clampage...)
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