When SilverStream 1.0 first appeared on the scene, many Webmasters and system administrators didn’t know what to make of it — who had really thought about serving applications from a separate server working apart from the Web server? But thanks to the success of SilverStream, application servers are becoming more prevalent in the enterprise — and SilverStream remains the leader in the application-server field.
SilverStream can be broken into three components:
- The actual server
- The application development environment
- The SilverStream Management Console (SMC), a Java-based administration program
SilverStream is designed to be implemented either on a single Solaris or Windows NT server or in a cluster of servers. For performance reasons, the SilverStream Application features database connection pooling, application object caching, and server-based transaction management. To ensure that requests get sent to the proper machine, SilverStream features multithreaded load balancing across multiple machines, multiple processes, and multiple threads. When enabled in a cluster, SilverStream provides server-based automatic restart features and application replication to ensure that session data is never lost. In addition, developers have available a persistent session object JavaBean — a server-side JavaBean that can be used with any SilverStream database to replicate session information.
SilverStream can be broken into three components: The actual server,
the application development environment, and the SilverStream Management Console.
Application servers tend to be closely tied to vendors’ other applications; the Oracle Application Server, for instance, is tied closely to Oracle 8. Since SilverStream is an independent vendor, it doesn’t need to worry about protecting turf in the database-management field. As a result, the database connectivity in SilverStream 2.0 is an area where the server really stands out from the competition. There are drivers for Microsoft SQL Server and Access, Oracle, Sybase, IBM DB/2, and Informix. ODBC and ODBC connectivity is also available for other products. This high level of interactivity extends to other application platforms and ERP platforms: a Notes interface ships with SilverStream and data connectors are promised for SAP and PeopleSoft products.
Another way that SilverStream differentiates itself from the other mass of application servers is its object-oriented HTML programming environment. You can build an application from scratch or use one of several wizards to automate the process of determining data sources and how will they will be displayed on the resulting HTML page. You don’t need to know any HTML coding to generate relatively sophisticated applications. SilverStream also supports CORBA as a native data object, which means that data objects can be distributed anywhere on the network. Data objects can also be encapsulated into reusable objects through a Business Object Designer.
The development process is simple: you use a wizard to begin designing your applications. SilverStream offers drag-down controls for routine data-management tasks, while controls can be bound to columns in a database or an object. As you code, you can work in either a WYSIWYG mode (showing you how the page will look when rendered in a Web browser) or HTML mode, displaying all the HTML tags.
As you design the page, you tap into some nifty technology underlying SilverStream’s dynamic page-generation capabilities. You create HTML runtime Java classes (built upon the Java. Servlet standard) executed by the application server. These classes then dynamically serve HTML applications. SilverStream claims that this process will lead to faster development times and more sophisticated applications.
New in 2.0 is enhanced Java support, the SilverStream Management Console (SMC), Data Source Object technology, an object-oriented Page Designer for HTML development, a Business Object Designer, and Y2K compliance. The new JRunner application has built-in application caching and encryption, allowing Java programs to be run in the browser as applets or as applications run from a workstation using JRunner. As mentioned before, the SilverStream Management Console (SMC) is a Java-based administration program. It allows remote browser-based management, and it can also be run as a standalone Java application. From it, you can control all aspects of the application server, as well as overseeing all performance aspects of the application-server cluster.
Pricing for SilverStream depends on the configuration and capabilities. The server is actually sold as part of an Application Deployment Server (ADS), which also includes the load-balancing modules, the Fulcrum full-text search engine, and RSA and DSA encryption software. On the plus side, servers are sold without per-user limitations and are licensed on the basis of the number of processors used. However, on the minus side, development tools are sold separately, ranging between $495 and $4,995, depending on the number of developer seats. Developer packs are sold with limited-user application servers for group testing.
The server itself starts at $8,500 for a 1 processor/unlimited users license and scales to $17,000 for 2 processors, $34,000 for 4 processors, and $51,000 for 6 processors. While these prices are on the higher side, they are competitive with other application servers on the market. SilverStream pioneered the application-server market with the original release of the SilverStream application server. With the release of 2.0, SilverStream keeps pushing the envelope on what should be expected from an enterprise-level application server.
Pros: 7 Load balancing, 7 Application replication and automatic restart, 7 Exemplary Java support, 7 Advanced dynamic page-generation capabilities
Cons: 7 Only UNIX version is on Solaris, 7 Expensive
Version Reviewed: 2.5
Reviewed by: Kevin Reichard
Last Updated: 8/8/01
Date of Original Review: 4/27/99