How can I get diffrence time of 2 ip address?

Question

Hi all,

I have a table with 3 column(source ipaddress, destination ipaddress, start time), which every source ipaddress assign many record of every destination like below.

source ip         destination ip       stime
0.0.0.2             0.0.0.4               5
0.0.0.1             0.0.0.3                4
0.0.0.2             0.0.0.4               7
0.0.0.2             0.0.0.4                10
0.0.0.2              0.0.0.3              4
 
I want to get diffrence of stime between 2 ip addresses like 0.0.0.2 and 0.0.0.4. I must compute diffrence stime of first and second record of these ip adresses like : (7-5) and second record with third (10-7).

Let me know how can I do?

I should do for every source ip address with destination ip addresses.