Financial Messages Overview 
All financial messages must contain the Originator and MessageType. A financial message can be either a Request or Response message type.
The top level structure of the Financial Request Message is shown below:
Syntax
<FinancialMessage>
<KeyToken>
</KeyToken>
<Originator>
</Originator>
<MessageType>
</MessageType>
<Request>
</Request>
</FinancialMessage>
The top level structure of the Financial Response Message is shown below:
Syntax
<FinancialMessage>
<KeyToken>
</KeyToken>
<Originator>
</Originator>
<MessageType>
</MessageType>
<Request>
</Request>
<Response>
</Response>
</FinancialMessage>
Notes:
All the elements that are optional can be omitted; they will only be required for some transaction types.
The Originator element and MessageType must always be present in the request as well as the Response elements.
The Request element will be present in the Request as well as Response messages.