[comp.unix.i386] What is UDP/IP and is there an DOS X server that uses it?

m1jjh00@fed.frb.gov (Jeffrey J. Hallman) (06/04/90)

The latest issue of Unix Today! has an article "The Lowdown  on
DOS/Unix Links" by Roy Lee which compares several methods of
networking DOS and Unix machines.  In his discussion of PC-Interface,
Lee says "PC-Interface actually runs on top of UDP/IP instead of
TCP/IP to further reduce protocol overhead."  This raises the two
questions in my Subject line above, namely, what is UDP/IP and can I
run an X server on a DOS machine using it rather than TCP/IP?  All of
the DOS X servers I've read about use TCP/IP to communicate with host
systems, but according to its' creators, X-Windows can run on any
reliable network.  Assuming UDP/IP is reliable, (is it?) it should be
possible to run X over it and save the expense of buying a TCP/IP
package for each DOS machine on the network.  Am I nuts, or what?

cpcahil@virtech.uucp (Conor P. Cahill) (06/05/90)

In article <M1JJH00.90Jun4104509@msuws2.fed.frb.gov> m1jjh00@fed.frb.gov (Jeffrey J. Hallman) writes:
>Lee says "PC-Interface actually runs on top of UDP/IP instead of
>TCP/IP to further reduce protocol overhead."  This raises the two
>questions in my Subject line above, namely, what is UDP/IP and can I
>run an X server on a DOS machine using it rather than TCP/IP?  All of

Just think of the U in Udp standing for Unreliable.  There is no reliability
checking of data transmitted on a UDP layer which forces the processes
at each end to perform the reliability checking themselves.  NFS has it's
own reliability code and can therefor run ontop of UDP.  It could also
run ontop of TCP, but that is inefficient due to the redundant reliability
checking.

>reliable network.  Assuming UDP/IP is reliable, (is it?) it should be
>possible to run X over it and save the expense of buying a TCP/IP
>package for each DOS machine on the network.  Am I nuts, or what?

UDP is not reliable and therefor I don't think it can be used as a 
standard layer under the X protocol.  However, even if it could, you
wouldn't save yourself too much since you would still have to buy the
UDP/IP package for each machine.

-- 
Conor P. Cahill            (703)430-9247        Virtual Technologies, Inc.,
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