Business-to-consumer network

The basic electronic commerce Web site is a business-to-consumer network. In the first phase of Internet growth, businesses typically focus on simply creating a Web presence. Corporate information and product catalogs are converted to digital formats and made available on the Web site. Shopping can be available by providing e-mail addresses, telephone and fax numbers, and even automated forms. True online shopping, however, is not available. All transactions have an inherent latency because humans need to process the order.

In phase two, businesses eliminate this latency and streamline their sales operation by implementing secure shopping carts for direct online purchases. Synchronization with warehouse databases and integration with banking systems are crucial to completing these sales transactions. Product that is not available cannot be sold, and a customer's account cannot be charged for that item. Likewise, a product cannot be taken from inventory and shipped to a customer until a valid financial transaction occurs.

In the third phase, the corporate Web site evolves into a dynamic presentation site where the consumer begins to take on the aspects of a client and is provided with personalized content.

The following scenerio includes both Load Balancer and Caching Proxy.

IMPORTANT: Caching Proxy is available on all Edge component installations, with the following exceptions:

Phase 1

Figure 14 shows a small commercial Web site designed to provide efficient catalog browsing. All client requests pass through the firewall to a Dispatcher that routes the requests to a cluster of proxy servers with active caches that act as surrogate servers to the Web servers. Metric servers are colocated with the proxy servers to provide load-balancing data to the Dispatcher. This arrangement reduces the network load on the Web servers and isolates them from direct contact with the Internet.

Figure 14. Business to consumer network (Phase 1)
This graphic depicts a sample basic business to consumer network

Phase 2

Figure 15 shows a the second phase of evolution for a commercial Web site designed to provide efficient catalog browsing and fast, secure shopping carts for potential customers. All customer requests are routed to the appropriate branch of the network by a Dispatcher that separates requests based on Internet protocol. HTTP requests go to the static Web site; HTTPS requests go to the shopping network. The primary, static Web site is still served by a cluster of proxy servers with active caches that acts as a surrogate for the Web servers. This part of the network mirrors the network in the first phase.

The electronic commerce portion of the Web site is also served by a cluster of proxy servers. However, the Caching Proxy nodes are enhanced with several plug-in modules. The SSL handshaking is offloaded to a cryptographic hardware card, and authentication is performed through the Access Manager (formerly Policy Director) plug-in. A Dynamic Caching plug-in reduces the workload on the WebSphere® Application Server by storing common data. A plug-in on the application server invalidates objects in the Dynacache when necessary.

All shopping cart applications are tied into the customer database that was used to authenticate the user. This prevents the user from having to enter personal information into the system twice, once for authentication and once for shopping.

This network divides traffic according to client usage, removing the processor-intensive SSL authentication and electronic commerce shopping carts from the primary Web site. This dual-track Web site allows the network administrator to tune the various servers to provide excellent performance based on the role of the server within the network.

Figure 15. Business to consumer network (Phase 2)
This graphic depicts a sample business to consumer network

Phase 3

Figure 16 shows the third phase of the evolution of a business-to-consumer network, with the static Web adopting a dynamic presentation method. The proxy server cluster has been enhanced to support the caching of dynamic Web content and assembly of page fragments written to comply with the Edge Side Includes (ESI) protocol. Rather than using server-side include mechanisms to build Web pages on the content servers and then propagating these client-specific, noncacheable, pages through the entire network, ESI mechanisms permit pages to be assembled from cached content at the edge of the network, thereby reducing bandwidth consumption and decreasing response time.

ESI mechanisms are crucial in this third-phase scenario, where each client receives a personalized home page from the Web site. The building blocks of these pages are retrieved from a series of WebSphere Application Servers. Application servers containing sensitive business logic and ties to secure databases are isolated behind a firewall.

Figure 16. Business to consumer network (Phase 3)
This graphic depicts a sample business to consumer network