i would suggest you a logic.if you feel that is cool then you can go for it.
see ,,first you should generate a random number.
let us say that is 20.
now open a flatfile ,just write this number in the first row.
next what you will have to do is just generate 4 more numbers from 20. might be 20|21|22|23|24
<<all this step should be in a single go.
And also it should not be in an append mode.
then read this numbers from this flat file for the link display.and assign these values to each link.
1st link will be 20th.
2nd link will be 21st one
In next refresh the random number will be changing and also the follwing numbers will be changing.That time it might be a sequance like 89|90|91|92|93.
so it will be keep on changing.make sure that this number is not going beyond the total number of links(ie, if it is more than 100 it should start writing from 0).
i have had faced similar situation many times.but i have implemented this logic successfully.
But only one problem it is having is ,only one link will fetch randomly.rest of the links will be generate from that random number.
if we are checking the condition it may take some time to process this script .so i thought this may be the easy solution for this..
actually i am not getting any other logic now.
probably others can suggest you a wonderful logic for solving your problem.
i hope above thing is clear to you.If you have any problem,then simply post that here.
"The fear of the LORD is the beginning of knowledge..."