 |
 Carousel Bookcase with three rotating tiers $200.00 Time Remaining: 39m Buy It Now for only: $400.00 |
 Mahogany Three Tier $150.00 Time Remaining: 5d 3h 21m Buy It Now for only: $150.00 |
 Alera Three Tier Rolling Cart in Black ALESW543018BA $99.75 Time Remaining: 25d 11h 57m Buy It Now for only: $99.75 |
 Three Tier Black TV Stand for TVs up to 32 $62.55 Time Remaining: 29d 8h 16m Buy It Now for only: $62.55 |
 Honey Can Do Three Tier Bamboo Shoe Rack in Natural Bamboo SHO 01601 $25.99 Time Remaining: 22d 9h Buy It Now for only: $25.99 |
 Winsome Milan Storage Long Three Tier Shelf Or Bookcase $139.98 Time Remaining: 26d 23h 7m Buy It Now for only: $139.98 |
 Three Tier TV Stand by Convenience Concepts $64.48 Time Remaining: 9d 2h 47m Buy It Now for only: $64.48 |
 Glass Three Tier Table by Convenience Concepts $60.57 Time Remaining: 9d 2h 47m Buy It Now for only: $60.57 |
 Three Tier Storage Shelves Rack With Without Casters $39.99 Time Remaining: 12d 16h 56m Buy It Now for only: $39.99 |
 Maitland Smith Three Tier Black and Gold Lacquered Occasional Table $539.00 Time Remaining: 1d 17h 57m Buy It Now for only: $539.00 |
 BRASS THREE TIER TABLE Vintage PLEASE ASK ABOUT SHIPPING $474.99 Time Remaining: 4d 3h 20m Buy It Now for only: $474.99 |
 OIA Three Tier Shoe Rack in Black 97223 $49.99 Time Remaining: 7d 1h 42m Buy It Now for only: $49.99 |
 Winsome Milan Storage Three Tier Shelf Or Bookcase $100.00 Time Remaining: 26d 23h 27m Buy It Now for only: $100.00 |
 Sierra Contemporary Solid Wood Three Tier Bed Side End Table Nightstand $335.34 Time Remaining: 3d 10h Buy It Now for only: $335.34 |
 A Frame Black Wood Three Tier Book Storage Shelf $81.82 Time Remaining: 11d 21h 2m Buy It Now for only: $81.82 |
 Winsome Basics 39 H Black Folding Three Tier Bookshelf 20896 $61.99 Time Remaining: 8d 17h 55m Buy It Now for only: $61.99 |
 Winsome Studio Three Tier Bookshelf $109.09 Time Remaining: 21d 21h 7m Buy It Now for only: $109.09 |
 Brand New Expresso 48 H Three Tier Bookcase For Sale $159.00 Time Remaining: 19d 17h 13m Buy It Now for only: $159.00 |
 Glass Three Tier Round Table by Convenience Concepts $69.99 Time Remaining: 9d 2h 47m Buy It Now for only: $69.99 |
 International Concepts Mission 36 H Three Tier Bookshelf SH 3630M $108.88 Time Remaining: 1d 7h 58m Buy It Now for only: $108.88 |
 CHINTALY SMOKE GLASS THREE TIER COCKTAIL TABLE 7280 CT $339.38 Time Remaining: 22d 4h 52m Buy It Now for only: $339.38 |
 Antique English Walnut Three Tier Table Dumbwaiter Buffet Table Stunning $1,399.00 Time Remaining: 14h 12m Buy It Now for only: $1,399.00 |
 Rolodex Mesh Three Tier Desk Shelf 22341 TN $6.60 Time Remaining: 1d 2h 46m |
 30 Tall Brown Three Tier Pedestal Accent Table Poplar Wood Cottage Style Stand $238.00 Time Remaining: 3h Buy It Now for only: $238.00 |
 Beautiful Three Tier Ornate Elm Stand Not An Antique $119.00 Time Remaining: 10d 19h 18m Buy It Now for only: $119.00 |
 Honey Can Do Three Tier Chrome Storage Shelves $72.98 Time Remaining: 16d 21h 22m Buy It Now for only: $72.98 |
 Cyan Design 03073 Bamboo Three Tier Stand In Gold $395.00 Time Remaining: 16d 8h 32m Buy It Now for only: $395.00 |
 Beringer Three Tier Motion Glass Coffee Table $649.99 Time Remaining: 13d 21h 49m Buy It Now for only: $649.99 |
 Brand New Basics 39 H Antique Walnut Folding Three Tier Bookshelf For Sale $189.00 Time Remaining: 6d 21h 58m Buy It Now for only: $189.00 |
 ZEVI VINTAGE 1970s ITALIAN CHROME GLASS ETAGERE THREE TIER SIDE TABLE $1,016.28 Time Remaining: 24d 20h 34m Buy It Now for only: $1,016.28 |
 Northfield Three Tier Bookshelf by Convenience Concepts R4 0113 $196.00 Time Remaining: 1d 18h 8m Buy It Now for only: $196.00 |
 European Three Tiered Step Table $218.00 Time Remaining: 21d 20h 48m Buy It Now for only: $218.00 |
 CHINTALY THREE TIER MOTION GLASS COCKTAIL TABLE 8049 CT $756.91 Time Remaining: 22d 5h 2m Buy It Now for only: $756.91 |
 Honey Can Do Three Tier Canvas Shoe Rack in Charcoal SHO 01818 $34.99 Time Remaining: 7d 14h 14m Buy It Now for only: $34.99 |
 Solid Iron Rustic Industrial Three Tier Accent End Table w Pull Out Drawer NEW $269.99 Time Remaining: 6d 7h 34m Buy It Now for only: $269.99 |
 OIA Espresso Three Tier Resin Tall Tower $46.98 Time Remaining: 11d 2h 42m Buy It Now for only: $46.98 |
 Three Tier Wooden Accent Stand in Brown Cherry Finish Wood End Table w Shelves $298.00 Time Remaining: 5h 54m Buy It Now for only: $298.00 |
 29 Tall Three Tier Storage Shelf Side Table Bookcase Accent End Cherry Finish $318.00 Time Remaining: 2h 48m Buy It Now for only: $318.00 |
 30 Tall Three Tier Storage Shelf Side Table Bookcase Accent End Cherry Finish $318.00 Time Remaining: 3h 9m Buy It Now for only: $318.00 |
 OIA Espresso Three Tier Resin Wide Shelf $52.98 Time Remaining: 10d 21h 25m Buy It Now for only: $52.98 |
 Storage and Organization Three Tier Revolving Shoe Tree in Antique Bronze 2138 $35.99 Time Remaining: 15d 1h 29m Buy It Now for only: $35.99 |
 Winsome Leo Three Tier Wide Shelves $89.98 Time Remaining: 9h 42m Buy It Now for only: $89.98 |
 Storage and Organization Three Tier Revolving Shoe Tree in Chrome 2131 $29.99 Time Remaining: 20d 18h 14m Buy It Now for only: $29.99 |
 hand painted violet table roses three tier corner table $75.00 Time Remaining: 4d 7h 28m Buy It Now for only: $110.00 |
 Winsome Expresso 48 H Three Tier Bookcase 92348 $94.50 Time Remaining: 20d 20h 52m Buy It Now for only: $94.50 |
 NEW DEFLECTO 390204 Three Tier Document Organizer Plastic 13 3 8 x 3 1 2 x 11 $36.97 Time Remaining: 13d 7h 16m Buy It Now for only: $36.97 |
 Lauren Ralph Lauren Home Avalon Collection Three Tier End Table 0501 41 New $699.00 Time Remaining: 7d 22h 24m Buy It Now for only: $699.00 |
 Bridgewater Gallery Classic Glass Series Three Tier TV Stand $113.59 Time Remaining: 11d 23h 34m Buy It Now for only: $113.59 |
 OIA Three Tier Shoe Shelf in Natural Chrome 17034 $39.00 Time Remaining: 7d 7h 28m Buy It Now for only: $39.00 |
 Honey Can Do Three Tier Shoe Tree in Chrome SHO 01482 $30.99 Time Remaining: 7d 4h 43m Buy It Now for only: $30.99 |
 GRAMMERCY ACCENT TABLE THREE TIER TABLE BLACK FINISH FREE SHIPPING $189.00 Time Remaining: 6d 16h 24m Buy It Now for only: $189.00 |
 Bamboo Three Tier Round Table in Gold Finish with Glass Shelves $337.25 Time Remaining: 10d 2h 52m Buy It Now for only: $337.25 |
 Lite Source Three Tier TV Stand and Shelf in Silver Chrome with Frosted Glass $246.00 Time Remaining: 7d 10h 26m Buy It Now for only: $246.00 |
 White finish wood three tier storage cabinet with glass $225.70 Time Remaining: 2d 22h 56m Buy It Now for only: $225.70 |
 Adesso Cascade Three Tier Swivel End Table WK5106 22 $202.30 Time Remaining: 15d 1h 57m Buy It Now for only: $202.30 |
 Marquez Three Tier Black Coffee Table $399.99 Time Remaining: 13d 21h 49m Buy It Now for only: $399.99 |
 Lite Source Three Tier 18 TV Stand in Silver LSH 5617 $239.00 Time Remaining: 2h 38m Buy It Now for only: $239.00 |
 AA Importing Three Tier Nesting Side Table in Black with Red Accent 80206 $367.99 Time Remaining: 27d 17h 17m Buy It Now for only: $367.99 |
 Black finish wood three tier storage cabinet with glass $225.70 Time Remaining: 2d 22h 55m Buy It Now for only: $225.70 |
 Lite Source Three Tier 17 TV Stand in Silver Chrome LSH 5614 $326.00 Time Remaining: 13d 3h 1m Buy It Now for only: $326.00 |
 Three Tier 45 Tv Console in Black Finish by Coaster $207.66 Time Remaining: 14d 8h 35m Buy It Now for only: $207.66 |
 Brown Three Tier Nesting Side Table AA Importing 8020 $275.93 Time Remaining: 4d 4h 21m Buy It Now for only: $275.93 |
 Chintaly Three Tier Swivel Oval Table in Black 7280 CT $369.00 Time Remaining: 15d 1h 46m Buy It Now for only: $369.00 |
 OIA Devine Three Tier Shelf in Black 39654 $315.00 Time Remaining: 15d 2h 7m Buy It Now for only: $315.00 |
Describe a possible architecture for a three-tier web bsaed client server application?
XML related.
Generally a three tiered architecture consists of a backend (database), a business tier, and a presentation tier.
The backend tier would consist of all the databases or other backend services which the application would consume. The interface into this tier is generally some sort of database or webservice protocol (ODBC or JDBC for databases, SOAP etc. for webservices.)
The business tier is where all of the application logic and control flow resides. This is generally where the majority of the application code lives. The purpose of this tier is to encapsulate the logic of the application in to coarse-grained services which can be consumed by the presentation tier. The business tier is responsible for receiving input from the presentation tier, making any necessary updates or queries to the backend tier, and providing output back to the presentation tier. The main motivation for creating this tier and using a tierd architecture to begin with is to decouple the user interface from the backend systems used by the application.
The presentation tier encapulates the user interface. Since your system is web based this would likely consist of ASP pages or Java servlets running on some sort of a web server. The presentation tie serves as the single point of interface with the user and then communicates with the business tier through the services it exposes. This communication could happen in a number of ways. Remote object calls using something like CORBA or .Net remoting, web service invocation, or external messaging services are all options for communication between the presentation and business tiers.
As I said before, the important thing is that the presentation tier stay decoupled from the backend by interfacing only with the business tier. This way if something about the database changes, the business tier is the only part of the application that has to change and all the user interface code can remain isolated.
Warhammer Online Production Podcast #3- Tier RvR Explanation