SOA, Enterprise Service BUS

BUS-words only?
SOA - Service oriented applications are mirroring the internet mashup-hype in a professional (say "chargeable") way. Approaching customized information on all levels of a company is definitely useful and boosts productivity. The theoretical approach of SOA is therefore a nondisputable advantage for companies of a certain size. The practical implementation, however, usually through a "Enterprise service bus" (ESB) has yet to be proven.
Consulting companies join the bandwaggon by wildly selling SOA and ESB to their clients - although a common definition of ESB has not been found yet. Early adopters will have to fight to find cost-effective solutions.

Until then, good theoretical approaches can be found here:
http://www.redbooks.ibm.com/redbooks/pdfs/sg246346.pdf
http://www.gi-ev.de/service/informatiklexikon/informatiklexikon-detailansicht/meldung/118/
http://www.till-rausch.de/assets/baxml/soa_akt.pdf

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