LYU9901-Travel NetLYU9901-Travel Net

Supervisor: Prof. Michael R. Lyu

Students: Ho Chi Ho Malcolm

Lau Chi Ho Arthur

(Presentation on 29-02-2000)

OutlineOutline

• Progress on first term

• Progress on second term

• Current Progress

• Future Plans

Work Done in 1st TermWork Done in 1st Term

• Set up an online web application - TravelNet on a NT web server

• Implement different functions of TravelNet using Java Servlet and HTML

Flight SearchFlight Search

• Search Flights on preferences of users

• Type of Search: One-way

• Principle: Call Airline Manager of each airline to query and access its own database for information on flights

Travel ShopTravel Shop

• Selling of travel related accessories such as luggage, map, guide book, etc

• Principle: A shop basket system which records items bought and initiates the payment system when checkout.

Travel GuidesTravel Guides

• Providing textual information on Cities covered by TravelNet

• Principle: pure HTML pages

MembershipMembership

• Require users to register first before using our services for better management and promotion

• Allow the change of personal information after login

• Principle: Maintain an user account database and login verification system

SecuritySecurity

• Necessary for user login and payment

• Consideration: Convenience and compatibility in browser environment

• Use of SSL between browser and web server

Work done in this term

• Payment Gateway

• Enhancement of Online shop

• Enhancement of Flight Search

Payment Gateway for TravelNetPayment Gateway for TravelNet

• To be a more realistic system

• Simulate payment in a secure way

• In this part:– Description of communication between

merchant and Payment Gateway (PG)– Performance measure of a payment transaction

Communication methodCommunication method

• Asymmetric key encryption on a TCP connection.

• Receiver use it’s own private key to decrypt message.

• Sender use receiver’s public key to encrypt message.

• Keys with 512 bit-length

• Hard to decrypt for hackers even with public key

• Merchant fill in client object and issue a start operation

Merchant (TravelNet)

Payment Gateway (PG)

Performance: Threaded ModelPerformance: Threaded Model

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Average Total CheckOut Time Average Time spent on PG

Performance: Non-Threaded ModelPerformance: Non-Threaded Model

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Number of concurrent users

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Enhancement of Online ShopEnhancement of Online Shop

• Dynamic generation of shopping item pages

• Allow easy maintenance

Enhancement of Flight SearchEnhancement of Flight Search

• Implementation of Round-Trip Search

• Display of search result– shown more complete information– sort result by time

Current ProgressCurrent Progress

• Implementing Itinerary Management System

• Investigating CORBA Integration

• Investigating JSP

Itinerary ManagementItinerary Management

• Maintain Users’ Flight Itinerary• Allow users to reserve flights eventually• Basic Functions:

– View items– Add items– Delete items– Reserve items to Airline

Itinerary Management(2)Itinerary Management(2)

• Will be finished soon so as to finalize the system for CORBA integration

CORBA IntegrationCORBA Integration

• CORBA - general standard on developing distributed programs

• Refer to CSC5110 for details!

CORBA Integration(2)CORBA Integration(2)

• Why CORBA in TravelNet?

• Existence of distributed component:– e.g. Airlines’ Databases on Flights

• Current Approach: Airline Manager resides on TravelNet to be called, which lacks parallelism & increase the load

CORBA Integration(3)CORBA Integration(3)

• CORBA Approach: Airline Manager resides on each airline server, to increase parallelism and decrease TravelNet’s server load

• More benefits: the use of Object Activation Daemon(OAD) for better resources allocation

CORBA Integration(4)CORBA Integration(4)

• Challenge:– the integration of CORBA is not simple– CORBA is commonly used in Applets and

Application but not Servlet

• Tools:– Visibroker for Java

• Today’s Web sites want to display dynamic content based on user and session.

• Mixing the "static" content of HTML files with "directives" for accessing or generating dynamic content.

• Java Server Pages provide server-side scripting support for generating web pages with combined static and dynamic content.

Introduction to JSPIntroduction to JSP

Displaying dynamic contentDisplaying dynamic content

• Common Gateway Interface (CGI)

• Active Server Pages (ASP)

• Java Servlets & Java Server Page (JSP)

JSP featuresJSP features

• Combines the worlds of HTML and Java Servlet programming

• Similar to HTML pages with new tags to control the generation of dynamic content

• Pre-compilation of JSP to Servlet which is responsible for generating dynamic pages

• Reside in application server memory (pre-load OR 1st access)

Why use JSP?Why use JSP?

• Platform independent

• Fast Response

• Reusability nature with Java classes or Java Beans

JSP JSP ContentContent

• Standard HTML + Tags for scripting in the Java language. • Tags like:

– <jsp:useBean> :Locates or instantiates a Beam with a specific name and scope

– <% code fragment %>: Contains a code fragment valid in page scripting language

– <%= expression %>: return expression value to output stream (client browser).

• JSP will finally be compiled to Servlets to access Beans

Compilation of JSPCompilation of JSP

• .jsp file will be compiled to be a Servlet

• Auto compile on – the first request of a .jsp file– the first request after changes on a .jsp file

• No compilation is needed if there is no update– Generate output (HTML) by Servlet in memory– Can be pre-loaded

•Request from browser to JSP of HTTP server

•Servlet request the Bean

•Bean request information from back-ends

•JSP response requested information to browser

TIME JSP18:35:20

Request = http://host/Time.jsp

Output on Client Browser

<HTML><H1>TIME JSP</H1><%java.util.Date dt = new java.util.Date(System.currentTimeMillis() );%>

<%=dt.getHours()%> : <%=dt.getMinutes()%>: <%=dt.getSeconds()%></HTML>

Time.jsp

Simple ExampleSimple Example

Future PlansFuture Plans

• Finalize the existing system

• Integration of CORBA

• Enhancement to the system, e.g JSP

• Other possible features depends on time

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