On Dec 14, 2007 10:55 PM, Simon Nash <[EMAIL PROTECTED]> wrote: > > "ESB" is much (mis)used as a marketing term. By those standards, > Tuscany is probably one already :-) But we'd probably want to > have some clear technical idea of what an ESB is before we decide > whether we want to put Tuscany under the (increasingly crowded) > ESB umbrella.
I think ESB should be recognized as an architectural pattern. If there is rather much confusion about what an ESB is, this may indicate that the pattern isn't well defined. Otherwise it would be more or less easy to determine whether Tuscany fulfills what the pattern is specifying, no? > > Somebody told me recently that ESBs are about virtualized service > endpoints. So there's a layer somewhere that can map virtual > endpoints to real endpoints, and can change the real endpoints > even though the virtual endpoints (as specified by application > code) stay the same. Hummm I've been told that service virtualization is a SOA principle thus isn't tightly coupled to an ESB. Quote: "There has been talk about dynamically provisioned services for years now. The problem is that even ESBs bind the service invocation too tightly to the service implementation." [1] It's even more interesting what will be virtualized :) * The actual location of the service (i.e. the FQDN or an IP address) * The service protocol (OpenESB also supports server-side virtualization of the service protocol [3]) * I was also once told that virtualization will be used to abstract different service implementations and thus the requestor may provide certain quality of service criteria to the virtual service endpoint which then delegates the request to the appropriate service according to the QoS criteria. * etc. Refs: [1] http://rourkem.com/soa/matt-quinn-on-service-virtualization.html [2] http://websphere.sys-con.com/read/467329.htm (Unifying Grid Virtualization, SaaS and SOA) [3] http://blogs.sun.com/tientien/entry/web_service_virtualization --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
