To All Concerned:
I am offering the following comments on the two messages which have been sent over the internet concerning DIFAX on the Internet provided by Alden.
Alden values constructive feedback about the manner in which services requested
are received. It is through this feedback that we are able to improve our
products and services to you our customers.
We at Alden want to hear your concerns and would very much appreciate a
personal communication when you believe you have not received the proper
attention to your problem.
I can be reached through e-mail by sending a message to highlandsw@xxxxxxxxx or
by phoning me at 508-366-8851 extension 2408. Please feel free to contact me at
William H Highlands
Manager, Operations and Communications Alden Electronics
______________________________ Reply Separator ________________________________
Subject: Re: difax problems on IDD ... wondering how Universal?
Author: davidw@xxxxxxxx at hailmail Date: 12/20/95 00:09
Paul Ruscher writes:
Haven't seen much traffic here lately, but we have noticed with increasing
frequency over past few months problems with IDD Difax from Alden. Many times
calls to report problems or request backups are futile, as we don't always get
a response to our phone/email queries, which usually come from our weather
If this happens, please let me know by a phone call or e-mail message.
At best, we seem to lose one complete upper air/model cycle per week, and
often more than that. It often seems that Alden never gets the maps on their
disk for backup and so we can never retrieve them. Difax is dying, I
know...but for the time being it is still a service that is paid for. Are
satellite users experiencing same kind of problems IDD users do? Is NWS
having problems getting Difax products to Alden, so that they can't get them
out to the Unidata sites? Are other IDD sites experiencing same kinds of
We'd appreciate some comments from other sites on this one...David Knight's
post helped prompt this request, and a visit to the IDD stats pages reveal that
we are not much worse off than other sites.
David Wojtowicz wrote:
Up until recently we were getting DIFAX via satellite. It was very reliable
and the few times we lost maps were due to problems on our end like a jammed
We've been on IDD DIFAX for a month or so now and the service has not been
great. Some specific complaints:
1) Reliability: IDD in general has had many problems as of late that the folks
at Alden and Unidata have been working very hard to solve. Many of the problems
such as frequent network outages are well beyond what they can control.
Despite this, IDD DIFAX tends to be less reliable then the IDD FOS data even
though they enter IDD at the same site. This morning for example (while we
were without maps for 10 hours) FOS data was getting thru just fine while I was
not able to LDMping the DIFAX server, thunder.
Part of this problem is likely due to the old slow machine they are running the
DIFAX IDD on now with old LDM software. Hopefully this will improve a good bit
as they most to a new system running LDM5 over the next week or two as I
You have defined the major part of the problem. We will be updating the LDM
software on thunder in early January and at that time some of the current
problems will disappear. As you pointed out, the regular IDD data is sent by a
different machine running different software than that employed for the DIFAX
products. Recently we have experienced a few problems changing over from the
Sun OS that we were running to the Solaris OS we are now using on the LDM
machines forwarding the FOS data. That is now behind us and we can move forward.
2) Alden's lack of interest in the service. As I understand it IDD DIFAX
customers represent a rather tiny portion of Alden's customer base...and
therefore recieve an equivalent portion of their attention.
We do not have a lack of interest in you as a customer. If you were a smaller
portion we do not want to forget we are providing you a service.
The last several times I've called their service number to inquire about an
outage, I've ended up having to explain what IDD DIFAX is to the person I end
up talking to.... who isn't even aware that they offer such a service.. They
often start by asking me if our dish is working, etc. even though I explain
carefully that we get the data via the Internet.
Thanks for the feedback on this one. We will have to intensify our training
To be fair, when I've managed to directly contact Mark Franklin or one of the few others there that knows what's going on, they've been very helpful.
Thanks. I know Mark will appreciate that comment.
One might suspect that the less informed others I've talked to were the same
people I spoke with several years back who could talk you through major surgery
on the guts of one of those old wet paper chart recorders. I was always amazed
at how well they really knew their stuff....perhaps its just that nobody there
has bothered to explain the newer technologies to them.
I believe some are and some are new. It should not matter, you should be taken
care of and we will work harder to do that.
3) While the satellite broadcast maps came in like clockwork, the IDD DIFAX
maps come in much more at random....Sometimes there will be nothing for a few
hours and then suddenly a burst of a dozen maps. They all still get there, but
if you are looking at the hourly radar summary for example, its nicer to have
it come in in the same hour it was issued in.
This is a problem which we are working with Nearnet, our internet provider to
overcome. We have some bottle necks and we are working to locate them and
resolve the difficulties.
As it was explained to me, the IDD DIFAX maps come from their system by which
one can call up and request a map be sent to one's fax machine. This was
logical for them since that system already stored the maps in G3 fax format.
The problem here is though, that presumably, that system doesn't get the maps
until they go out on the standard satellite broadcast. Then it has to crunch
them for a while to get the in the correct format, etc. Then finally it has to
be sent into the IDD system. Sometimes this takes longer than at other times.
Our system and anyone receiving the data over our satellite system receives the
data at the same time. Our system does have to convert the data from a raster
scan product into a G3 format. This only takes a small amount of time. From
this system, the files are sent to thunder which then transmits them on the
internet to you our customer. This whole process should be completed in a
matter of minutes and most of the times that is the case. If the files are
held up it usually can be traced to a problem with the internet throughput.
4) The new 2XXX numbering system is based on the product numbers in their telephone fax
chart service rather than the traditional "D" numbers we're all familiar with.
This would be fine except for the fact there are fewer 2XXX numbers used than the D
numbering system had. Several D numbers map into the same 2XXX number. For
example....the 9Z Radar Summary is issued as D099 The 10Z Radar summary is issued as
D110. In Alden's 2XXX numbering system, they are come out as 2080. (In fact all 24
Radar Summaries, which all have seperate D#'s, end up as 2080.) The same is true for
other types of products. This makes it more difficult to automatically identify specific
products for special handling such as whether to print or not to print.
I attempt to convert back to D#'s here since our users are more familiar with
them by using a simple lookup table....the problem is that it didn't work since
one 2XXX number could be any of more than a dozen D#'s in some cases. Attempts
to guess based on time have been unsucessful because of the irregularity at
which maps are transmitted. (i.e Is that the 10Z radar summary coming in or
just a late 9Z one?)
I'm not arguing that we must go back to D#'s since one set of numbers is as
good as another, but am rather asking for a finer granularity in distinguishing
Alden did not know this was a problem. We will do some investigation on how to
better define the charts. Do you have any suggestions?
5) I've had problems with edges of maps being cut off that I don't recall happeing on the old
system. I also am having trouble getting the "wings" or "part2 extensions" on
the sfc analysis to come out at the same size...though I've taken reasonable care to ensure that my
printing process is not rescaling them. (Though I am not ruling this out)
I am pretty confident that we are not altering the size of the products. Let me
know how you make out on this one.
Please understand that I am not trying to just sit and complain. I understand
that such things can be complicated. I've had just as many if not more problems
that were entirely at our end during our first month on the new system while I
try to iron out the bugs in our processing system. And certainly I will not
blame any one but myself for that. The above are just some of the issues that I
see beyond my realm of control...and offer them as constructive criticism.
Still, we are paying for the service, so we should expect a certain level of
comittment on Alden's part to provide it well and reliably.
I could not agree with you more.