Subject: Re[2]: difax problems on IDD ... wondering how Univ

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December 21,1995
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 
station manager.

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 
data losses?

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.

Paul Ruscher

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 
printer, etc.

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 
understand it.

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.

True statement.

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 
between charts.

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.
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