Unit 9 - Current Web Applications

CO22007 Web Development Methods Tom McEwan 30th April 2001

Current Web Applications

Coursework IssuesSecurityExample Application Areasbreak for 10 minutesPlug-in Documentation … and Why?Possible applications for NITSS

Current Web Applications

Unit Learning Outcomes Describe security issues relating both to web

content and web users Example Application Areas - Browser Suites,

Medicine & Music Create a release letter that documents

installation issues Differentiate between web material that is

copyright and/or protected and discuss the ethical issues in accessing different types

Current Web Applications

Module Learning Outcomes 2: Identify current and future application areas

for the world wide web

4: Download files from the world wide web.

5: Download plug-ins from the world wide web.

6: Create simple web-sites combining text and graphics.

7: Understand copyright considerations in relation to the world wide web

Coursework One

Average was … average (54%) Vast majority passing, but marks combined Many failed to read questions totally Spread slightly skewed to top end see

chartPlagiarism Guidance

Many online histories of the Internet/Web and they tend to steal from each other

Anyone may resubmit item 1 for max 4/10

Coursework 2

Ambiguity of submissions dateDue date extended to Monday week

13 (21st May)At tutorials - guidance on items

Cw1 Item 1 (average 56%)

For the benefit of the board of directors, write a short paper describing the history of the Web, how creating this site will benefit the business, and identifying the key issues for phase one

Many failed to go back to 1945, nor up to 1993 Lack of clear-cut benefits, and poor presentation Few justified prototype approach to stimulate

requirements gathering, and demonstrate web technology

Cw1 Item 2 (average 55%)

Define an outline specification of how the web-site might look and work, along with a framework for evaluation of each prototype.

Specifications often overly wordy/detailed Appearance is a matter for early discussion - choice

of fonts, colours, layout (sample screen), frames or not, all to be grounded in HTML standards - as well as actual font size, use browser font sizes

Framework based upon more than “your good taste”. Not everyone provided evidence to back up their design approach - few frameworks were clear

Cw1 Item 3 (average 50%)

Identify, from the various requirements, and comparison with existing suppliers, the functionality required.

... form of your choosing, ... of five different activities that users of the site might carry out… navigation diagram

Discuss the user’s conflicting requirements

Evaluate 5 competitor sites (or fewer better!)

PACT -> scenarios or sample activities

Many left unfinished

Security - some issues

Content Prevent unauthorized changes en route Prevent snooping Guarantee who supplied it

Users Protect confidential data Preserve anonymity Non-repudiation (for merchant’s benefit)

Activity

In groups of 2 or 3…What scare-stories have you heard

about information on the WWW?Do they have any foundation?How would you protect against

them?

Security

Check for the padlock (frames issue)Encryption - makes it hard for people

to see the file.Certification - guarantees who sent it.

Browsers can be configured to ask user to confirm when entering and leaving a secure a site, or when receiving files without certification (untrusted files).

Security - Military Spec

128-bit Encryption can be cracked by football-pitches full of super computers

People had downloaded it anywaySo the US government now permits its

exportPrevious classed as a military weapon!c.f. Japan & Playstation 2

Security - Spoof Sites

Like setting up a fake ATM on the high street

Search engines looking for “Buy BMW online” - links to a dodgy URL in South America

“Secure Site”, padlocks and all,

Security

Sign at Taipei International Airport: “Welcome to Taipei Arms smugglers will be executed”

Carrying data on a laptop into a country can be a criminal offence So can downloading it

EU tradition - data protection lawsUS tradition - site’s privacy policy

Security - Firewalls

Only 4 billion addresses, sad types hack at random.

Keeps the outside world out, and the inside world in, except when authorised

Detect whether information & commands coming in are valid

Industrial strength protection £1-2000, but free/cheap solutions for consumer

NCC Business Information Security Survey (1999)

Significant security breaches in 41% of companies with 10-99 employees.

Average cost per breach was £1,165. In smaller companies it was more

expensive, almost £3,000 per time.

Security - Home PC

ADSL & Cable Modem (once and while working!!) Permanent Live connection to Internet PcPro (Mar 2001) discussed attacks -

logged several a day on ADSL line, and none on the cable modem

Your fridge could be looted, your TiVO set to record the wrong programme, your online banking details set free!

Example Application Areas

Browsers integrated into larger tool-sets IE linked to Windows, Outlook, but also

networking, ActiveX, media player Netscape has Messenger, Composer, AOL

Instant Messenger, groupwareLike programming languages, uuthoring

tools like Director and Authorware can build browsing objects into larger applications

Example Application Areas

Music - http://www.digmedia.cc“Free software - free as in speech, not as

in beer” (Richard Stallman)Content owners starting to protect AND

promote online (useful to other industries) Limit free plays Free for a month Subscription

Example - Health and the Web

Two week wait for a doctor’s appointment five minutes to put your problems across need to prepare - or be very pushy :)

“Sinking feeling when the patient comes in with a pile of WWW printouts” If it’s on the Internet, it doesn’t make it true Australian government 1998 - 1400 quack sites

Example - Online Health

Several recent instances of people finding treatments or treatment centres from online sources

But “a little knowledge” can still be “a dangerous thing”. Would you be your own gas-fitter?

Online Health

American goverment portal to health sites www.healthfinder.org/ UK equivalent http://omni.ac.uk/ Dept of Health www.open.gov.uk/doh/dhhome.htm British Medical Journal www.bmj.com Pharmaceutical information www.pharmweb.net/ The Lancet www.lancet.com Reviews of other health sites www.jr2.ox.ac.uk/bandolier/ British Healthcare Internet Association http://bhia.org Medline - the database of medical research

http://medlineplus.nim.nih.gov/medlineplus Patient leaflets www.healthtouch.com NHSOnline

Intermission

Ten minutes

Release Letters

Why? To stop people asking you questions To get people to use your work To be able to update and maintain multiple

versions, adapted for multiple clientsWhat?

What’s asked for in the coursework Today - installation issues

Plug-in Documentation

Many companies are unwilling to consider using pages that require plug-ins

Why? In small groups write down some of the

reasons why

Plug-in Documentation

Long time to download Word and Acrobat both 8Mb plus

Take up a lot of disk space above - each expands to ~ 15Mb

Conflicts with existing working systemsMight not work with minority browsers

and emerging devices WebTV and PDAs might use HTML v 2.0

Plug-in Documentation

Your responsibility - be proactive about issues for the customer and their computers the end-users and their computers

Analyse the risksDocument the processes to install

and uninstall

Word

http://office.microsoft.com/2000/downloaddetails/wd97vwr32.htm

Note the size of the download! But also the effective tone and style of the

installation instructions. Many system administrators would prefer

a list of actual files installed date/timestamps and version numbers registry changes made.

This ensures that any potential conflicts can be analysed.

Acrobat

http://www.adobe.com/products/acrobat/readstep2.html (2001) describes the 8.8Mb download required to view Acrobat pages. Some will prefer to get this from magazine cover CDs!

If your end-user is an EU-based Palmpilot user they may find the following unpalatable to download their 5.5Mb plug-in:

“If you reside in the European Union, please indicate your consent that the personal information you have provided may be transferred and stored in countries outside the EU, including the United States. If you fail to provide your consent, you will not be permitted to download the beta software.”

The consequences of consenting are described at http://www.adobe.com/misc/privacy.html (2001).

Acrobat

Printing to file the contents of rs405eng.exe (the installation file for Acrobat 4.05): D:\essent\apps\Acrobat\rs405eng.exe Name Modified Size layout.bin 03/11/99 10:01 590 data1.hdr 03/11/99 10:01 32,468 data1.cab 03/11/99 10:01 469 ... AcroRd32.exe 03/11/99 09:38 2,333,184 Cooltype.dll 26/10/99 15:26 886,272 Movie32.api 22/10/99 10:24 111,616 etc...

Flash

Note: Flash animations are very much smaller than animated GIFs, and that Macromedia claim more PCs have Flash than Javascript

Plug-in is very small - 250k to download, but bundled with most OS and browsers

Flash.ini reveals that Reg Main Path=Communicator

Reg Relative Path=Plugins/Macromedia/Shockwave Flash

Version=4.60.0.98111

File0=npswf32.dll

Flash

De Facto standard for scalable, animated vector graphics on the web, but no longer part of the emerging W3C SVG standard http://www.macromedia.com/software/flash/open/faq/

(2001)

Alternative? http://www.adobe.com/svg/overview/svg.html (2001)

w3C working group on scalable vector graphics at http://www.w3.org/Graphics/SVG/Overview.htm8 (2001)

http://broadway.cs.nott.ac.uk/projects/SVG/flash2svg/ (2001) describes a Flash to SVG converter

Possible applications for Napier IT Skills-shop

If you were a customer would you want: Junk email? (spam)

Info on developments in your listed skills? Discounted books on subjects relevant to

your skill-set (or that others like you buy) To put samples of your code online for

prospective employers A link to your home page

Potential Areas

If you put code samples online then why not act as a software component exchange

You would want your work protectedYou would want contracts to assure

payment and to know the bona fides of your customers