Greetings,

I am trying to understand the ICMP timestamp (type 13) queries .
There is a unix tool ICMP Query that can be used to send ICMP
type 13 message (TIMESTAMP) and type 17 messages( ADDRESS MASK
REQUEST) .

When I am sending ICMP type 13 queries on a Linux and Solaris
machine , it is giving me the exact time of the remote machine.
The following result shows that.

""
[root@gdrd5 ~]# icmpquery -t 172.16.1.2
172.16.1.2 :10:09:56
[root@gdrd5 ~]# icmpquery -t 172.16.1.2
172.16.1.2 :10:09:58
""

The result is matching the time on the remote machine.

But if I send the same request to a windows machine ,
I am getting results which I am not able to interpret.The
following are the results on a windows machine .

[root@gdrd5 ~]# icmpquery -t 172.16.16.31
172.16.16.31 : 08:52:31
[root@gdrd5 ~]# icmpquery -t 172.16.16.31
172.16.16.31 : 10:07:13
[root@gdrd5 ~]# icmpquery -t 172.16.16.31
172.16.16.31 : 19:43:24
[root@gdrd5 ~]# icmpquery -t 172.16.16.31
172.16.16.31 : 00:26:59

Also I am not getting any result when I am sending
ICMP type 17 messages (Address Mask) as the
following result shows .

[root@gdrd5 ~]# icmpquery -m 172.16.16.31
[root@gdrd5 ~]# icmpquery -m 172.16.1.2
[root@gdrd5 ~]# icmpquery -m 172.16.16.25
Unknown ICMP message received (type 17)

Is ICMP type 17 messages are not supported by OS these days .
Because I had stopped the firewall on these systems and
tried the test.But still not getting any reply for ICMP type 17 message.

Please help me in interpreting the ICMP timestamp result from a
windows machine and also the reason why there is no response
for ICMP Address Mask request.

Cheers
b zaman