The EDD Protocol

The EDD protocol is compact and binary in nature (as opposed to an XML based scheme, for example). Data is presented in little endian format, and no marshalling (e.g., Corba or some other IDL interpretation) is used. EDD is intended to be lightweight and be fairly bandwidth efficient, but flexible enough to be useful for generalized data representation.

The EDD protocol is somewhat independent of the hardware link layer implementation, though at present has only been used with TCP based IP ethernet connections. The EDD protocol requires that message packets not be fragmented or presented out of order (or if they are underlying link layer protocols handle re-assembly).

For TCP/IP based EDD connections, the default port number for the server socket is defined by DEFAULT_EDD_TCP_PORT_NO. At present, there is no discovery protocol defined for locating EDD devices on a local area network.

All EDD messages (client or server) must start with an EDD message header (tsEDDMsgHdr) data block. The following table defines the messages used by the EDD protocol.

MessageSourceDestination
tsEDDPlotDescReqMsgEDD ClientEDD Server
tsEDDPlotDescMsgEDD ServerEDD Client
tsEDDPlotMsgEDD ServerEDD Client
tsEDDSourceDataReqMsgEDD ClientEDD Server
tsEDDSourceDescReqMsgEDD ClientEDD Server
tsEDDSourceDescMsgEDD ServerEDD Client
tsEDDImageDescReqMsgEDD ClientEDD Server
tsEDDImageDescMsgEDD ServerEDD Client
tsEDDImageMsgEDD ServerEDD Client

Generated on Sat Apr 25 17:20:44 2009 for EDD by  doxygen 1.5.8