Computing 205/406 & IT8
Tutorial #4
- In the lecture, it was claimed that the file sharing used in NFS on
the department's Unix system was transparent to the user, but that the
approach taken in the Novell PC laboratories was not, to the same
extent. What does this mean?
- Explain why a binary mode FTP transfer of a PC text file to a Unix
system results in a corrupted file. Then explain why binary mode is
the default on the implementation available in the department's PC
labs...
- Why does the control connection in FTP need to use the TELNET
NVT specification?
- BSD Unix introduced a file transfer utility called rcp, analogous to
rlogin. What does this do?
- Why is the XDR library needed in NFS? Under what conditions is the
XDR scheme inefficient?
- (Research questions) Are there alternatives to NFS for Unix filesystem
sharing? Can NFS be used other than between Unix systems?
Practical exercises:
- Use ftp (and its enhanced version ncftp) to copy a file from one
system to another. Use anonymous FTP to repeat the operations in
slide 4 of the lecture. Use netscape to perform anonymous FTP.
- Use ftp to transfer a file from a machine to itself, and then from
the machine to another machine on the same LAN. Do the data
transfer rates surprise you?
- Experiment with FTP to see how fast you can transfer a file between
two Unix systems on a LAN, when the network is busy and when it is
idle. Explain the result. Compare the rates of transfer for FTP and NFS
on the same LAN. Do the data transfer rates surprise you?
This tutorial is also available in PostScript format.
Phil Scott