The TollGateTM Concept
Internet Software Distribution
Using the Internet to access software services rather than to transport software applications to the end consumer is becoming the preferred role of software distribution. To support this model, capable network infrastructure and control programs are required. TollGateTM has been designed for this emerging model. In order to meet this opportunity TollGateTM was designed to:
- Scale across servers
- Allow Web Clustering and
- Allow for Integration
Power of N Scalability
In order to compete cost-effectively in the emerging application service marketplace, ISVs will need to provide software that can scale to be used by millions of subscribers. This requirement for scalability applies equally to both the application services themselves, and the infrastructure software required to control the subscription and distribution processes.
Scalability must not come at a cost of greater complexity and/or expense. Any initiative designed to achieve such scalability must support the definition of web content, subscriber memberships, subscription contracts, and payments for use with a straightforward and non-labor intensive approach.
Above all, the technology required to support a large-scale deployment of application services over the Internet must be "over-built" and "carrier-grade". TollGateTM meets these criteria for Power of N Scalability.
Power of N Web Server Clustering
TollGateTM enabled application services are designed to work with clustered web servers, and requests for services are routed automatically during a session to the "least used i.e. most available web server". The routing of requests from one web server to another is transparent to the end user and is known as "load balancing"
Clustered web servers provide the scalability and the redundancy required for large scale application services deployment over the Internet. To achieve the design goals of secure scalability, purpose-built next generation web applications are required.
Load Balancing has been used for years with static web content. We have adopted and refined these technologies for use with complex business applications. The next generation of rental application services will be far from static content presentation platforms. They will have to transparently maintain the application state for each user, as they are routed from server to server within the web cluster.
Directory Services Integration
A trend towards wide-scale deployment of Directory Services technology is underway. These services are designed to replace the myriad of application-specific membership stores found in most organizations. Adoption of this technology, based on the Lightweight Directory Access Protocol (LDAP), is a pre-requisite to the tightly integrated next generation of business application services.
TollGateTM embraces and extends this Directory Services technology, and utilizes several of its key capabilities to support a large-scale Membership model. The LDAP technology used by TollGateTM has a proven capacity, and consequently TollGateTM is able to automatically replicate membership changes around the world from server to server. This provides additional scalability support through the use of mirrored authentication servers.
Subscriber/users are authenticated against the operating system not against application-specific (i.e. home-grown membership databases). A common data store for membership data aids in future integration efforts.