HP 3000 Manuals

Using NS3000/XL Network Services

Three-Node Model 

NFT transfers files according to the model shown in Figure 5-1.  There
are three logical participants in the file transfer activity:  initiator,
producer, and consumer.  This model is called the three-node model.
According to the three-node model, the initiator, located on the system
where the transfer originated, receives the request and initiates the
transfer.  The producer, located on the same node as the source file,
accesses that file and "produces" the data that is to be transferred.
The consumer, residing on the same node as the target file, "consumes"
the data and writes it into the target file.  All three participants are
logically distinct.  All three participants can be on separate nodes; the
transfer request does not have to originate from either the source or the
target node.  It is also possible for any two or all three participants
to reside on the same node.

This method, coupled with the ability to include a logon command string
as part of the  DSCOPY command, provides considerable flexibility.
Because the initiation of the transfer request is independent of the
producing and consuming functions, you don't have to explicitly log on to
a remote source or target node.  If you supply an appropriate logon
sequence in the transfer request or in a prior  DSLINE command, NFT will
create a session on a remote source or target node if one does not exist
already.  If all the systems involved (as many as three) belong to the
same NS3000/XL network, you can transfer a file between any two nodes in
the network and you can initiate the transfer from any node in the
network.


          Figure 5-1.  Three-Node Model 

MPE/iX 5.0 Documentation