As more companies look to adopt a service-oriented architecture (SOA) approach for their IT systems, users who’ve already forged ahead with SOA recommend beginning modestly.

SOA is an increasingly popular way for organizations to develop and manage their IT systems through reusable technologies and present information previously locked up in legacy applications as Web services.

"Start small. Pick a project that’s manageable and well-defined and that you have influence over," said Russell Rodrigue, senior vice president of business technology planning at TD Banknorth. He spoke Thursday at AMR Research’s Executive Leadership Conference in Boston.

TD Banknorth, a U.S. banking and financial services company, has its headquarters in Portland, Maine, and has grown rapidly by acquisition, picking up 23 companies in the past eight years.

When purchasing a new company, TD Banknorth used to employ a "rip-and-replace model" to deal with the new acquisition’s IT systems, Rodrigue said. Realizing this was very costly, the company more recently adopted SOA.

In defining its SOA approach, the bank brought in BEA Systems, IBM and WebMethods to set up individual proof-of-concept SOA implementations. Each vendor was given four weeks to get Web services up and running. While BEA and IBM took more than 3 weeks to get their implementations going, WebMethods had an operational system in three days.

Car and truck rental agency Avis Budget Group of Parsippany, N.J., began its work on what evolved into an SOA deployment back in 2000.

John Turato, vice president of strategy at Avis, feels comfortable cherry-picking the best pieces of technologies from a variety of vendors including BEA, IBM and Oracle.

At present, there’s too much overlap in what the different vendors are trying to get users to buy as one vendor offers its own application server and repository, while another provides its own different repository plus a registry. Users are waiting for some clarity in the SOA market, he said. "There’ll be a shake-out after a while or IBM will buy them all," Turato quipped.

One measure of the success of the SOA approach so far is a drop in development costs using Web services, Rodrigue said. The price tag per service has fallen from thousands to dollars to around $500, since more and more the development work involves reusing existing technology. Over the course of developing five major SOA projects, Turato at Avis has seen an 80 percent decrease in development time.

While outsourcing some application development, Avis has been careful to retain its enterprise architecture skills in-house. "We like to feel we can get out of trouble quicker than we got into it," Turato said, quoting from Kelly’s Heroes, a war movie and black comedy from 1970.