Is NServiceBus an ESB at all

Question

Is NServiceBus a ESB or lightweight ESB at all? or is it more like WCF with durable/ reliable messaging? It looks to me more like a messaging framework than ESB.

just wa

Answer 1

Enterprise service bus is a compound SOA pattern. If you look into Thomas Earl's books here are the patterns that ESB includes

1. Broker (Protocol Bridging, Data Format and Data Model Transformation)
2. Intermediate Routing
3. Asynchronous Queuing
4. Reliable messing
5. Event Driven
6. Policy Centralization
7. Rules Centralization

NServiceBus to my knowledge (limited) does apply some of these patterns - rest (ex: Rules Centralization and Policy Centralization) are expected to be implemented by the user. By this definition, BizTalk is also an ESB.

An important thing to keep in mind, is that by using NServiceBus or Biztalk or anything else does not make you SOA. In fact, if not used properly, you might find yourself tied to a vendor, defeating the first principal of SOA - Vendor neutrality.