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1. What is the role of a data mediator interceptor? Can you cite an example of how mediation works say for a component A with reference R that references a service S in component B.?
   The interceptor gets added by the connector. A's outbound wire and B's inbound wire describe the datatypes their implementations can support. When the wire ends are connected the connector adds the interceptor if mediation is needed.
   One job of a transport binding is to convert an in-memory physical representation to a suitable set of bits on the network (aka serialization and deserialization). Rather than reinvent the different transports we reuse existing implementations such as Axis2 or RMI. As such we need to convert the physical representation on our internal wire with that used by the transport. So, for example, Axis2 only understands AXIOM so in a reference we need to convert the user's physical representation to AXIOM and in a service we need to convert the AXIOM generated by the transport into the form the user's implementation requires. The steps could be described as follows:
   1)
   1. A calls reference R with physical Java object X(java)
   2)
   1. X is placed on R's outbound wire
      3) data mediation converts X(java) to AXIOM object X(axiom)
      4) X(axiom) is placed on inbound wire for the Axis2 binding
      5) Axis2 binding serializes X(axiom) onto the network as XML
      6) Axis2 binding on the target deserializes the XML from the network to X(axiom)
      7) X(axiom) is placed on the outbound wire from the Axis2 binding
      8) data mediation converts X(axiom) to X(java) as needed by the target component
      9) X(java) is placed on B's inbound wire
      10) the target instance for B is invoked passing in X(java)
      An important thing to note here is that from the fabric's perspective we are dealing with two physical wires: the wire on the client connecting the source component A to the outbound Axis2 transport and the wire on the server connecting the inbound Axis2 transport to the target component B.
      From a global perspective there is one logical wire from A to B but because A and B are located on two different runtimes that logical wire gets split into two physical wires A->net and net->B.