The scp
command, which uses the SSH protocol to
copy files between
machines, is deeply wired into the fingers of many Linux users and
developers — doubly so for those of us who still think of it as a more
secure replacement for rcp.  Many users may be surprised to learn,
though, that the resemblance to rcp goes beyond the name; much of
the underlying protocol is the same as well.  That protocol is showing its
age, and the OpenSSH community has
considered it deprecated for a while.
Replacing scp in a way that keeps users happy may not be an easy
task, though.