Whitebeam Environment - Redbourne Case Study

Redbourne created the Whitebeam environment - and have harnessed the architecture to build a sophisticated operational environment. The resulting hosting environment is specifically suited for the hosting of mission critical e-business applications. Redbourne Integration Partners develop, test and implement applications on behalf of their clients within the Redbourne environment - a resilient implementation of a Whitebeam environment. Authorised end users can use these applications over the Internet using any web browser.

The Redbourne example is a good illustration of what can be achieved using the Whitebeam architecture. Below you will find some information on what Redbourne has accomplised.

Internet

The Internet can be considered a global interconnection of host computers over a TCP/IP network. End users gain access to the Internet via an ISP, typically by dialling a local telephone number. This local connection automatically gives end users access to products or services worldwide.

Browser

The browser is the end user application responsible for displaying the pages constructed by web servers. A user can request a web page by keying an appropriate URL (Uniform Resource Locator) or address. The location of the resource is resolved by the Internet.

Data Centre

Applications hosted within the Redbourne Data Centre are available to via the Internet. The Redbourne data centre is physically located in the Telehouse campus in Docklands, East London.

Telehouse offers a facility that is:

• Preferred by the UK's tier one Internet Service Providers (ISPs)
• Access controlled 24x7 through uniformed security staff, internal and external CCTV with time-lapse video recording, and use of proximity cards
• Resilient to power failures through the use of multiple mains electricity feeds, uninterruptible power supply (UPS) system, generator backup
• Resilient to connectivity equipment failure through use of redundant network components.

Redbourne provides a resilient high bandwidth connectivity service that is independent of any ISP and has multiple links to the Internet via LINX (London INternet eXchange). LINX is a small private network operated by tier one ISPs that routes Internet traffic through the UK when it originates from and is destined for the UK. This improves domestic response times and releases bandwidth for international traffic.

"The Redbourne Data Centre" white paper contains a more detailed discussion on this topic including hardware architecture, security architecture, and scalability.

Redbourne System Architecture

Robust e-business applications can be quickly developed and deployed using the Redbourne system. Such applications can leverage the core capabilities of the Whitebeam architecture, developed and tested originally by Redbourne, to implement bespoke and/or complex business processes through simple application programming interfaces or APIs.

The core of the Redbourne system, the 'Whitebeam' Open Source e-business development environment, is essentially a set of co-operating software components hosted at the Redbourne Data Centre. These software components play a key role in delivering application services to Redbourne partners and their clients.

Web Servers

Redbourne runs the industry standard Apache Web Server software on FreeBSD UNIX. The Web Server is responsible for serving web pages using the HTTP protocol (and the secure variant, HTTPS) over the Internet in response to URLs keyed by a user or generated by a Redbourne application. Redbourne operates a number of Web Servers for load balancing.

FreeBSD is a UNIX operating system that is specially stripped down to core functionality to optimise performance and security.

A configuration file defines how the Web server processes user requests based upon the received URL. In the Redbourne system, the Web server is configured to handle requests for static content and to delegate requests for dynamic content to Redbourne's Presentation Engine.

Client Applications

Each client application is essentially a set of files. These files will typically be a mixture of files that define static content (e.g. HTML presentation pages and gifs) and Redbourne pattern pages (RHTM).

Pattern pages are files that define any mixture of Redbourne dynamic content and normal static content.

Presentation Engine

A key element in the Redbourne system is the Whitebeam Presentation Engine. This does the work of 'executing' the Pattern Pages that that form the client application. The Presentation Engine finds and executes the Pattern Page that corresponds to a specific requested URL and dynamically generates a web page that is then delivered, to the requesting browser.

Each pattern page can contain server-side JavaScript, HTML/XML, and (client-side) JavaScript code. The Presentation Engine parses the pattern page to identify and process Whitebeam XML (eXtensible Mark-up Language) tags. XML tags convey document mark-up information to the Presentation Engine and to also define interfaces to back-end Templates.

The Presentation Engine validates and executes any server-side JavaScript that may include interactions with Redbourne Templates.

Templates

The Redbourne System has a number of templates that individually encapsulate a number of business or system functions or indeed processes. Templates are the software components that fulfil the dynamic behaviour and content of e-business applications through interactions with the Redbourne database.

Redbourne Templates are designed as shared software components that execute core e-business functions and processes. An e-business application can combine the behaviours of any number of Redbourne Templates to formulate complex business processes. Redbourne Templates, developed in a rigourous environment by skilled technicians, abstract complex data management and integrity into simple interfaces. As such, Redbourne Templates form the basis for rapidly developing and deploying robust e-business applications.

The interface to each Redbourne Template is defined within the Redbourne 'Resource Object Model' (ROM) that is similar to the common browser Document Object Model (DOM). The ROM is accessible from server-side JavaScript. The ROM has a top-level parent object, rb (resource base), whose immediate child objects typically map onto WhitebeamRedbourne Templates.

Database

Redbourne uses an IBM DB2 database to store dynamic data. The integrity of the database is maintained by the implicit relationships defined within and/or across tables in the database. The integrity of the data in the database is maintained by Redbourne Templates. By using the DB2 implementation of the Whitebeam templates Redbourne benefit from the superior performance and reliability of the IBM DB2 enterprise database.

Redbourne Solution - Key Features

Redbourne provides a secure and controlled environment for deploying dynamic e-business applications. The Redbourne solution inherently supports:

• Multiple browser sessions by any one end user.

• Recording of (browser) state or context information particularly useful in maintaining continuity between generated web pages. For instance, this allows a developer to implement a 'next' or 'previous' button on a Redbourne generated page that displays the correct set of results even if the user returns to the page via the browser's 'back' button having visited web pages of a different application.

• Client data privacy such that applications in a client's domain have access to that client's data.

• Multiple instances of hardware, software and data components for resilience and availability.

• Automated set up of clients through sophisticated and secure Administrative tools.

• Automated monitoring of the Redbourne system with real-time alerts to (remote) operational staff.