Called IBM WebSphere Portal Express, the product can run off of a single server and is designed to be simple to install and maintain. IBM said it has priced the product aggressively in order to attract smaller customers - it starts at $77 (£49) per user, with no minimum requirement for the number of users.
"Smaller businesses will welcome this because they don't have a large IT staff or any specific training around IBM technologies - or around any vendor's technologies," said Laura Ramos, an analyst with Giga Information Group.
Portals are Web sites where information can be aggregated and customised for employees, customers and partners. An internal portal might include an expenses application or let workers collaborate on a project, while an external portal could show details about product pricing and availability for a particular customer. The reusable content elements within portals are referred to as "portlets".
IBM said it had tried to make its product easy to deploy and manage. Using wizards and "a few mouse clicks", customers will be able to customise page layouts, add portlets or add new users, IBM said. The product also comes with IBM's application server and an LDAP directory.
All of IBM's smaller customers will be eligible for the product's low, per-user pricing, the company said. IBM said Microsoft's competing product, Microsoft SharePoint Portal Server, works out more expensive because Microsoft requires a minimum number of users in order for customers to receive discounts.
"What it boils down to is Microsoft has a $72 price per user and IBM has a $77 price per user," Ramos said. "IBM is saying you have to spend at least $4,000 (£2,550) with Microsoft before you get started. But that's only really going to matter in companies with something like 50 people; I think the sweet spot here is more like 250 people."
In recent months, IBM has stepped up markedly its efforts to attract small and medium-sized businesses. It said WebSphere Portal Express will be the first of several software products that it plans to launch aimed at this market.
Smaller businesses are likely to use portal products internally for the most part, rather than trying to rein in customers and suppliers, Ramos said. One exception might be for marketing purposes, she said, noting that portals can be used in conjunction with e-mail advertisements that direct potential customers back to a company's Web site.
WebSphere Portal Express is priced at $77 per intranet user, with a limit of 2,000 users per portal server, and $30,000 (£19,130) per processor for extranet use, with a limit of four processor licences per portal server.
It is due to be available for download from 31 October in English, Korean, Japanese, Simplified Chinese, Traditional Chinese, French, Spanish, German, Italian, Polish, Czechoslovakian, Brazilian Portuguese, Hebrew, and Turkish, the company said.
IBM has also announced a slightly more advanced version of the product WebSphere Portal Express Plus, that has the same functions along with added features such as instant messaging, group calendaring, document libraries, and document sharing and revision capabilities.
That product is priced at $122 (£77) per intranet user and $47,820 (£30,494) per processor for extranet use. The same limits apply, and availability is scheduled for the same date as for WebSphere Portal Express, in the same languages.