Whether you choose to use an ESB or SCA will probably be determined by what tech-
nologies you're already using. SCA usually has a lower initial cost for connecting to-
gether two specific things, but an ESB may have lower long-term costs because it's
a more general-purpose solution to an infrastructure problem.
SOAP over HTTP
Enterprise Service Bus
SOAP over HTTP
JMS with XSLT transform
Figure 11.4 An ESB acts as a common transport channel loosely connecting diverse endpoints. Com-
munications may be mediated with XSLT transforms or other adjustments to the content.
A number of ESB providers use OSG i for their internal architecture. But fewer of these
ESB s include support for user's OSG i bundles, and fewer still include enterprise OSG i
support in their runtime. But you do have some choices if you want to use your enter-
prise OSG i application with an ESB .
The most comprehensive enterprise OSG i support is arguably provided by Apache Ser-
viceMix. ServiceMix provides native hosting for your OSG i bundles and built-in Blue-
print support, based on Apache Aries. Some nice extensions mean Blueprint can even
be used to configure the message routing.
Closely related to ServiceMix is Fuse ESB , a productized offering of ServiceMix. Fuse
ESB is still open source, but commercial support subscriptions are available.
APACHE KARAF PLUS APACHE CAMEL
ServiceMix is based on a combination of Apache Karaf and Apache Camel, with fea-
tures to handle security, registries, and extra configuration. Some users find they don't