Question: what is Sandesha2? 

Answer: Sandesha2 is an implementation of WS-ReliableMessaging specification published by IBM, Microsoft, BEA and TIBCO. Sandesha2 was built on top of Axis2. Therefore by using Sandesha2 you can add reliable messaging capability to the web services hosted using Axis2. Sandesha2 can also be used with Axis2 client to interact with already hosted web services in a reliable manner. Please see sandesha2 user guide for more information on using Sandesha2. Read Sandesha2 Architecture guide to see how Sandesha2 work internally.
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