An ESB is a key building block of service-oriented architecture because it gets away from point-to-point messaging systems and implements general-purpose routing among an application and many other pieces of software, such as other apps or middleware messaging systems. The JBoss ESB 4.0 will be available in December.
JBoss' product is based on the Rosetta ESB created by Aviva Canada, Canada's second-largest insurer. Aviva built that ESB when it encountered integration problems rolling out Oracle Financials, before Oracle's Fusion Middleware was available. Aviva, a big user of JBoss Application Server, donated Rosetta ESB to JBoss, jump-starting its service bus offering.
Red Hat's moves beyond marketing the Linux operating system into new software markets have created tension with frequent allies such as IBM and Oracle. Red Hat bought JBoss this year.
The JBoss ESB can leverage JBoss Rules, a rules engine that can set policies for routing content. It supports the IBM WebSphereMQ, Apache ActiveMQ, and JBossMQ messaging systems.