Standards for Marshaled Data Packets
In the architecture described here, nothing has yet to be said about representation or format standards for the data that gets placed in marshaling packets. There is a good reason for this. In the Component Object Model architecture, the only two parties that have to agree on what goes into a marshaling packet are the code that marshals the data into the packet and the code that unmarshals it out again: the interface proxies and the interface stubs. So long as we are dealing only with intra-computer procedure calls (such as non-network), then we can reasonably assume that pairs of interface proxies and stubs are always installed together on the computer. In this situation, we have no need to specify a packet format standard; the packet format can safely be a private matter between the two piece of code.
However, once a network is involved, relying on the simultaneous installation of corresponding interface proxies and stubs (on different computers) is no longer a reasonable thing to do. Thus, when the a method invocation is in fact remoted over a network, it is strongly recommended that the data marshaled into the packet to conform to a published standard (NDR), though, as pointed out above, it is technically the interface-designer's responsibility to achieve this correspondence by whatever means he sees fit.