Connection verification.
This is a small project to help people with the tough decision: 'Should I go
to work?' Here we try to give a good reason to stay at home (when applicable).
Of course, if this website is not available, just go back to bed.
The 'should I go to work' prognosis is based upon measurements over the
last three days. Today is weighed the most of course and the weight decreases
as the days are further from the present. You can see the
source of this script if you are interested.
| Between 72 and 48 hours ago: | 0 | you might want to give it a try |
| Between 48 and 24 hours ago: | 0 | you might want to give it a try |
| Last 24 hours: | 0 | you might want to give it a try |
| Prognosis (with weigths 0.25 0.50 1.00): | 0 | you might want to give it a try |
And here is a nice graph which might help in making a decision of whether or
not to go to work.
What you see in the picture above is the non-responsiveness of the first
four hops. The green lines denote date boundaries.
On the x-axis we see the number of seconds since 1970-01-01 00:00:00 UTC and
for reading convenience the begin and ending time of the graph. On the y-axis
we see the hop number.
It is not uncommon for hops with a higher number to be unresponsive when one
of the lower numbered hops is unresponsive, because the path to the other
hops is blocked.
Presently, the hops are the following:
| 1: | m1gw.liacs.nl |
| 2: | bb.liacs.nl |
| 3: | gul-liacsgate.leidenuniv.nl |
| 4: | v1-1-1.1042.xsr01.amsterdam2a.surf.net |
The check works as follows: we send an icmp packet with TTL 1 to a remote
address (more than four hops away). If we don't get an error from the first hop
(TTL exceeded), we log its non-responsiveness. Then we increase the TTL to
check the second hop and so on.
All of this is done by a script that runs continuously
in the background. The generation of the image is done once an hour by
this script.
|
