Datalex Communications David Tracey david.traceydatalex.ie

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Datalex CommunicationsDavid
Traceydavid.tracey_at_datalex.ie
OMG Presentation (January 1999)
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Agenda

• Some examples from Datalex customers
• to illustrate some requirements/considerations
• Considerations for CORBA and Airlines
• as a starting point
• A sample data model
• to start the process!!!
• Whats next?
• some ideas

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Application Example 1
Cargo - automated warehouse
ALC Host
Windows 95/ NT Server or router
ALC
ALC
Warehouse System (relational DB)
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Application Example 1

• New and advanced warehouse system at hub airport
  - accessed locally via LAN
• Proprietary messages defined to interact with
  existing cargo application on existing mainframe
  for interoperation and access from other sites
• Would CORBA have helped?
• at present would not have been as quick or
  efficient to do? Absence of standards reduces the
  advantage of interoperating with other systems?
• but if cargo interfaces were standardised..

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Application Example 2
EDI (PADIS) Access
ALC Host
Windows 95/ NT Server or router
ALC
ALC Requests/Responses
PADIS Requests/Responses
Message Translation Middleware
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Application Example 2

• The Message Translation Middleware
• supported easy table-driven message conversion
  (with screen-scraping required)
• had EDI libraries
• relatively high speed
• multiple line handlers for comms protocols
• Would CORBA have helped?
• performance?
• ease of conversion with existing product
• CORBA IDL interfaces into message translation
  middleware may be useful to integrate with CORBA
  applications

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Application Example 3
Internet Booking Engine
ALC Host 1
Windows 95/NT Server or router
ALC Host 2
Internet Booking Engine
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Application Example 3

• Multiple Host Access (not just airline or GDS
  host)
• abstractions for the different systems are
  required - Objects are suitable
• every system is different and screen scraping
  needed
• ticketing - not yet (implies secure transactions
  and secure printing)
• All that Protocol conversion - why not do it all
  on host!?
• Fewer transactions than legacy networks (in
  future?!)
• Would CORBA have helped?
• Booking Engine to client (open way for new
  suitable apps)
• Booking Engine (and other apps) to host (host
  IIOP?)
• PUBLISHED interfaces defined in IDL useful in
  both cases

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Application Example 4
Package Holiday Access
Browser Access
Thompsons
Istel
Cosmos
Router
SunWorld
ALC
Windows NT IIS Server
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Application Example 4

• Access to multiple Videotex Hosts across X.25
• MessageTranslation and Screen Scraping for Web
  Requests/Responses
• Would CORBA help?
• Web Server to client (open way for new apps)
• client applications could use IDL interfaces?
• Web Server to host
• objects for common operations with specific
  handlers to map to specific host

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Considerations for CORBA Airlines

• Performance
• connection establishment, memory (leaks)
• want scalability, recovery and redundancy
• Galileo quote gt3000 requests per second peak
• Communications Lines
• many users on low speed lines (with quick
  response)
• not all IP, although MATIP gateways are being
  used.
• User Equipment
• lots of dumb terminals
• Do airlines/GDS want interoperability and where
  (or only across their applications)??????
• Select where CORBA is most suitable

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TPF Considerations

• It is a message-driven real-time executive -
  primary aim is quick message turn-around (CORBA
  will not match this!)
• Not so good for compute-intensive tasks (but
  faster hardware allowed it)
• IIOP on TPF?
• Back-end/post transaction applications, e.g.
  fraud analysis in Credit Card company, booking
  analysis in Airline company
• Requires work on TPF system to integrate apps
  with IIOP
• Primarily for Intranet connected users?
• Is it a way to remove need for screen scraping
  (published interfaces into IIOP enabled apps)?

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A Data Model

• Define access to services in terms of object/IDL
  interfaces allowing non-centralised CORBA
  services to be built using the TPF mainframe
• Client software can be written against defined
  (and hopefully industry standard or at least
  published) interfaces
• Sub-classes can cater for specific markets or
  specific implementations of a service
• Difficulty in adding new services to TPF systems,
  esp compute intensive services
• Reduce dependence on (TPF) mainframes?

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A Data Model - Object Layering

• Can we match the TMN Layered model?
• Map to TDRA?

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A Simple Data Model - Approach

• By specifying the business rules independent of
  its implementation in a computer system, the
  information model preserves the business of the
  business
• What and Why - not How!
• Abstract TPF connectivity into separate host
  access object(s)
• Abstract services and functions into
  host-independent classes (and instantiate
  appropriate subclass for selected host)
• customer services -flight availability, fare
  quote, booking
• also services for marketing, flight operations,
  airport ops etc

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A Sample Data Model

• Taken from Datalex Internet Booking Engines (IDL
  interfaces being produced)
• Several Packages of classes
• web related (e.g. logins, look feel -
  storefront)
• database access (holding engine data and some
  client information - such caching can reduce host
  accesses!)
• utility classes (ascii/ebcdic, date conversion)
• host access
• profiles

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A Sample Data Model

• Host Access Classes
• Consist of three main groups
• Communications API classes
• currently ALC specific and Videotex specific
• API primitive objects, e.g. open(), close(),
  hostIsAvailable(), methods to read configuration
  and map to IATA
• screen object with methods scrape(), readLine()
  etc
• Handler Classes
• HostServerRequest (e.g. AirAvailRequest)
• HostServerResponse (e.g. AirAvailResponse)
• Server Classes
• Specialised versions of Handler Classes for
  different hosts using Communications API objects
• Appropriate Request and Response objects are
  built and then serialised into messages.

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A Sample Data Model

• Example of a Handler Object
• A09MARDUBJFK0800-EIY4
• class AirAvailRequest extends HostServerRequest
• private City origin
• private City destination
• private Timestamp date
• private Airline carrier
• private String cabinclass
• private int adults
• private int children
• plus various get and set methods

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A Sample Data Model

• Profiles - to model the different entities and
  data collections involved (could be more
  structured)
• Address Objects - e.g. Address, City (Agency
  object has Address etc)
• Reservation Related Objects, e.g. AirLeg , Flight
• Person Objects, e.g. Passenger, Agent,
  Administrator
• Itinerary Objects, e.g. AirItinerary,
  HotelItinerary, CarItinerary

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A Sample Data Model

• Example of a Profile Object
• public class AirLeg
• private int id
• private Airline airline
• private CClass cclass
• private City deptcity
• private City destcity
• private Timestamp deptdate
• private Timestamp destdate
• private int flightnum
• private int stops
• private Person creator
• private String fareBasisCode
• plus various get and set routines

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Whats Next??

• Are we all interested enough in interoperability
  to give our time or just making sure we dont
  miss out?
• Should we
• Identify prioritise key applications
• Reservations and/or others such as DCS, Cargo etc
• Assign WG members to do first draft of data
  models for highest priority applications
• Draft an appropriate layered model?
• Identify other airlines adopting/considering
  CORBA and seek their ACTIVE participation
• Seek IATA involvement?