Sequenced Packet Exchange (SPX) is a protocol in the IPX/SPX protocol stack that corresponds to a connection-oriented transport layer protocol in the OSI model.
Being reliable and connection-oriented, it is analogous to the Transmission Control Protocol (TCP) of TCP/IP, but it is a datagram protocol, rather than a stream protocol.
Each SPX packet begins with a header with the following structure: The Connection Control fields contains 4 single-bit flags: The Datastream Type serves to close the SPX connection.
For this purpose two values are used: This computer networking article is a stub.
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