TriBand NU users BEWARE - part of your downloads during NU hours (00:00->08:00 IST)
may be charged to your non-NU quota of 1GB/mo.
While going through the session details for May/2006, I came to the
conclusion that the time on MTNL's TriBand billing system is
approximately 9-10 mins. ahead of IST.
I can say this with assurance because I schedule the downloads on my Linux
Intranet server to begin @ 00:02 and terminate @ 07:58. This server also
provides NTP services to other nodes on my LAN; the "ntpd" daemon on this
server keeps itself synchronized with reputed public NTP servers (e.g.
time-a.nist.gov) on the Internet.
At 23:59 and 07:59 hours this server also executes a script to reboot the ADSL
modem, thereby forcing distinct "pppoe" login sessions for NU and non-NU hours
respectively. After running the ADSL modem reboot script the server
shuts itself down at 08:00 hours. At this point of time, save the ADSL modem
all nodes are powered OFF i.e. no IP traffic on the LAN.
With such a scheduling system in place, I was certain that none of my downloads
would spill over to the non-NU hours and that the time stamps on MTNL's detailed
session reports would be in sync give or take 60 secs. at most.
However, on close examination of the "session details" I was surprised to see
downloads MBs being charged to my account and stopping at around 08:08:08 to
08:09:59 (see records marked * below). [To avoid these charges, I had to
terminate my download around 07:48 hours]
Another anamoly noted on the session details is "overlapping" pppoe
sessions! I have only one ADSL line/modem so how can overlapping pppoe
sessions be possible? (see records marked + below).
Every TELCO has access to highly accurate atomic clocks through which they can
set the time on their various equipment. Therefore IMHO MTNL, being an incumbent
TELCO, has no excuse for such big differences in their system times.
The point here is that when you publish a time for the NU hours it has to adhere to
some standard. In this case it is IST. We all understand that implicitly and
accordingly schedule our jobs to avail the service offered during that time.
In MTNL's case, this does not seem to be the case. In May it was 9-10 mins.
In future it may be worse than above. The consumer has no way of knowing the
time difference (from IST) on MTNL's billing system until **after** the fact.
Such practice on their part is plain wrong and I would venture to say they are
billing their NU Plan customers incorrectly. For May/06, a rough calculation shows 173MB,
that I thought was unmetered, was charged to my 1GB monthly quota - roughly
17.3%!
If you are subscribed to the NU Plan then monitor your downloads during NU hours.
Ensure that your computer's system time is reasonably accurate by synchronizing it
regularly, with a public NTP server and maintain logs of your download start
and end times. Compare your log with the "session details" from MTNL's report
@ http://register.mtnl.net.in.
Please post your own experience here to gauge the gravity of this issue.
Listed below is a pruned session detail report showing my findings.
Session History Details
Usage history of 'aaaabbbb' from 01-May-2006 to 31-May-2006
Start Date End Date Quantity Billed (MB)
+ 01/May/2006 00:05:11 01/May/2006 08:07:20 0.0191
+ 01/May/2006 08:05:34 02/May/2006 00:03:15 15.0432
+ 03/May/2006 00:04:37 03/May/2006 08:07:13 0.0257
+ 03/May/2006 08:05:42 04/May/2006 00:06:23 29.6274
+ 04/May/2006 00:04:42 04/May/2006 08:07:18 0.0103
+ 04/May/2006 08:05:48 04/May/2006 23:42:24 26.7329
+ 04/May/2006 23:40:46 04/May/2006 23:45:47 0.0171
+ 04/May/2006 23:44:00 04/May/2006 23:50:01 0.083
+ 04/May/2006 23:48:16 04/May/2006 23:56:24 0.2822
* 13/May/2006 00:05:24 13/May/2006 08:08:30 5.4775
* 14/May/2006 00:05:32 14/May/2006 08:08:08 6.0176
* 15/May/2006 00:05:37 15/May/2006 08:08:43 13.8309
* 16/May/2006 00:05:41 16/May/2006 08:08:47 13.9385
* 17/May/2006 00:05:46 17/May/2006 08:08:22 13.3174
* 18/May/2006 00:05:52 18/May/2006 08:08:28 13.1461
* 19/May/2006 00:05:54 19/May/2006 08:08:30 12.8393
* 20/May/2006 00:06:00 20/May/2006 08:08:36 13.687
* 22/May/2006 00:06:11 22/May/2006 08:08:47 10.8236
* 23/May/2006 00:06:15 23/May/2006 08:08:51 9.7693
* 26/May/2006 00:18:17 26/May/2006 08:09:21 14.5032
* 27/May/2006 00:06:37 27/May/2006 08:09:43 15.204
* 28/May/2006 00:06:41 28/May/2006 08:09:47 15.3887
* 29/May/2006 00:06:45 29/May/2006 08:09:51 15.1079
* 30/May/2006 00:03:52 30/May/2006 08:09:28 14.3707
+ 30/May/2006 08:07:59 30/May/2006 13:49:07 0.3732
+ 30/May/2006 13:47:32 30/May/2006 22:14:43 94.3865
+ 30/May/2006 22:56:59 31/May/2006 00:20:15 0.0424
*+ 31/May/2006 00:18:40 31/May/2006 08:09:43 1.2511
+ 31/May/2006 08:08:01 31/May/2006 23:40:37 18.4533
+ 31/May/2006 23:38:47 01/Jun/2006 08:09:59 0.0042 \
+ 31/May/2006 23:38:47 01/Jun/2006 08:09:59 0.002 / 2 records
for the same
pppoe session?
Legend:
* Download during NU hours spills over to Non-NU hours and is billed to Non-NU
quota.
+ Overlap in time stamps of consecutive pppoe sessions.
may be charged to your non-NU quota of 1GB/mo.
While going through the session details for May/2006, I came to the
conclusion that the time on MTNL's TriBand billing system is
approximately 9-10 mins. ahead of IST.
I can say this with assurance because I schedule the downloads on my Linux
Intranet server to begin @ 00:02 and terminate @ 07:58. This server also
provides NTP services to other nodes on my LAN; the "ntpd" daemon on this
server keeps itself synchronized with reputed public NTP servers (e.g.
time-a.nist.gov) on the Internet.
At 23:59 and 07:59 hours this server also executes a script to reboot the ADSL
modem, thereby forcing distinct "pppoe" login sessions for NU and non-NU hours
respectively. After running the ADSL modem reboot script the server
shuts itself down at 08:00 hours. At this point of time, save the ADSL modem
all nodes are powered OFF i.e. no IP traffic on the LAN.
With such a scheduling system in place, I was certain that none of my downloads
would spill over to the non-NU hours and that the time stamps on MTNL's detailed
session reports would be in sync give or take 60 secs. at most.
However, on close examination of the "session details" I was surprised to see
downloads MBs being charged to my account and stopping at around 08:08:08 to
08:09:59 (see records marked * below). [To avoid these charges, I had to
terminate my download around 07:48 hours]
Another anamoly noted on the session details is "overlapping" pppoe
sessions! I have only one ADSL line/modem so how can overlapping pppoe
sessions be possible? (see records marked + below).
Every TELCO has access to highly accurate atomic clocks through which they can
set the time on their various equipment. Therefore IMHO MTNL, being an incumbent
TELCO, has no excuse for such big differences in their system times.
The point here is that when you publish a time for the NU hours it has to adhere to
some standard. In this case it is IST. We all understand that implicitly and
accordingly schedule our jobs to avail the service offered during that time.
In MTNL's case, this does not seem to be the case. In May it was 9-10 mins.
In future it may be worse than above. The consumer has no way of knowing the
time difference (from IST) on MTNL's billing system until **after** the fact.
Such practice on their part is plain wrong and I would venture to say they are
billing their NU Plan customers incorrectly. For May/06, a rough calculation shows 173MB,
that I thought was unmetered, was charged to my 1GB monthly quota - roughly
17.3%!
If you are subscribed to the NU Plan then monitor your downloads during NU hours.
Ensure that your computer's system time is reasonably accurate by synchronizing it
regularly, with a public NTP server and maintain logs of your download start
and end times. Compare your log with the "session details" from MTNL's report
@ http://register.mtnl.net.in.
Please post your own experience here to gauge the gravity of this issue.
Listed below is a pruned session detail report showing my findings.
Session History Details
Usage history of 'aaaabbbb' from 01-May-2006 to 31-May-2006
Start Date End Date Quantity Billed (MB)
+ 01/May/2006 00:05:11 01/May/2006 08:07:20 0.0191
+ 01/May/2006 08:05:34 02/May/2006 00:03:15 15.0432
+ 03/May/2006 00:04:37 03/May/2006 08:07:13 0.0257
+ 03/May/2006 08:05:42 04/May/2006 00:06:23 29.6274
+ 04/May/2006 00:04:42 04/May/2006 08:07:18 0.0103
+ 04/May/2006 08:05:48 04/May/2006 23:42:24 26.7329
+ 04/May/2006 23:40:46 04/May/2006 23:45:47 0.0171
+ 04/May/2006 23:44:00 04/May/2006 23:50:01 0.083
+ 04/May/2006 23:48:16 04/May/2006 23:56:24 0.2822
* 13/May/2006 00:05:24 13/May/2006 08:08:30 5.4775
* 14/May/2006 00:05:32 14/May/2006 08:08:08 6.0176
* 15/May/2006 00:05:37 15/May/2006 08:08:43 13.8309
* 16/May/2006 00:05:41 16/May/2006 08:08:47 13.9385
* 17/May/2006 00:05:46 17/May/2006 08:08:22 13.3174
* 18/May/2006 00:05:52 18/May/2006 08:08:28 13.1461
* 19/May/2006 00:05:54 19/May/2006 08:08:30 12.8393
* 20/May/2006 00:06:00 20/May/2006 08:08:36 13.687
* 22/May/2006 00:06:11 22/May/2006 08:08:47 10.8236
* 23/May/2006 00:06:15 23/May/2006 08:08:51 9.7693
* 26/May/2006 00:18:17 26/May/2006 08:09:21 14.5032
* 27/May/2006 00:06:37 27/May/2006 08:09:43 15.204
* 28/May/2006 00:06:41 28/May/2006 08:09:47 15.3887
* 29/May/2006 00:06:45 29/May/2006 08:09:51 15.1079
* 30/May/2006 00:03:52 30/May/2006 08:09:28 14.3707
+ 30/May/2006 08:07:59 30/May/2006 13:49:07 0.3732
+ 30/May/2006 13:47:32 30/May/2006 22:14:43 94.3865
+ 30/May/2006 22:56:59 31/May/2006 00:20:15 0.0424
*+ 31/May/2006 00:18:40 31/May/2006 08:09:43 1.2511
+ 31/May/2006 08:08:01 31/May/2006 23:40:37 18.4533
+ 31/May/2006 23:38:47 01/Jun/2006 08:09:59 0.0042 \
+ 31/May/2006 23:38:47 01/Jun/2006 08:09:59 0.002 / 2 records
for the same
pppoe session?
Legend:
* Download during NU hours spills over to Non-NU hours and is billed to Non-NU
quota.
+ Overlap in time stamps of consecutive pppoe sessions.