rlogin, telnet and related commands

On the host having the X server :
ip a
	192.168.56.101

xhost +

ssh to remote host
	ssh -XY bob@192.168.56.102

on remote host without X :
echo $DISPLAY
	(nothing)

export DISPLAY='192.168.56.101:0.0'

start an X binary (xclock, xeyes, ...)

unset DISPLAY
echo $DISPLAY

back to the host with the X server :
xhost -