stevens@hsi.UUCP (Richard Stevens) (09/01/88)
I have some questions regarding XNS in general, and the XNS support in the 4.3 BSD kernel on a VAX: - What is XNS typically used for ? I assume its mainly for connecting with some Xerox hardware (printers, etc.). The reason I ask this is I recall about a year ago after the PS/2 came out, Ungermann Bass was moving their Ethernet adapter to the MicroChannel and was actually going to have XNS support *before* TCP/IP support, which surprised me. Are there any non-Xerox-hardware applications for XNS that are common (say similar to FTP, TELNET, etc.) ? - The Xerox manual states that "when a host is connected to more than one Ethernet, its 48-bit Ethernet address on all Ethernets is equal to its 48-bit host number." How do you select your 48-bit host number if you have more than one Ethernet interface ?? - The "Advanced 4.3 BSD Interprocess Communication Tutorial" (Sec. 5.12) states that the retransmission and duplicate supression code required to simulate the PEX protocol is "left as an exercise for the reader". Has anyone actually done this ?? - This same document states that PEX does duplicate supression, yet the Xerox manual ("Internet Transport Protocols", XNSS 028112, Dec. 1981) states that PEX does *not* perform any duplicate detection. Does the 4.3 Tutorial imply that since you have to simulate PEX with user code anyway, you might as well handle the duplicate detection ?? Thanks. Richard Stevens Health Systems International, New Haven, CT { uunet | yale } ! hsi ! stevens