[Asterisk-Users] OT: fax obsoleted? Was: Re: Fax via email

Steve Underwood steveu at coppice.org
Mon Jun 14 17:32:58 MST 2004

Lee Howard wrote:

> On 2004.06.11 20:47 Steve Underwood wrote:
>> The last info I got from a large FAX server is about a year old. It 
>> seems after several years of nothing much changing, FAX has suddenly 
>> taken a step up - kind of sad it should improve now it is obsolete :-)
> Fax was only partially obsoleted.  Users, developers, and 
> manufacturers alike all "foresaw" the end of fax with the coming of 
> the internet age.  They were only partially right.

People always overestimate short term change, and underestimate long 
term change. This is normal. FAX is still on the way out.

> In the old days, before the internet became ubiquitous, fax was used 
> quite extensively for document retrieval.  So if you had 
> document-information that you wanted to make available to others then 
> it was popular to put them up on a "fax-on-demand" service, and the 
> inquirer would either receive the documents to their fax machine via 
> polling, or by "fax back".  This usage of fax has almost completely 
> been obsoleted by the internet browser and by PDF.  In the old days 
> everyone who was anyone had a fax-on-demand service.  These days that 
> has been obsoleted by the website.  So yes, receiver-initiated 
> document exchange has largely been replaced by websites.


> There were also plenty of examples where people would use fax as a 
> means for small, somewhat unimportant, message communication - the 
> equivalent of today's e-mail.  Obviously e-mail has obsoleted this.

True, although FAX is still found convenient for sketches and markup.

> However, fax is still very much alive and healthy in the area of 
> imaged document exchange where the website or e-mail use would not be 
> appropriate - i.e., where the sender wants to initiate the document 
> exchange and the document is in a more-than-text form or image of some 
> kind (applications, completed applications, handwriting, etc.).  
> Furthermore, I don't see this usage of fax going away any time soon.  
> Indeed, technology seems to be providing better and better ways for 
> this to continue, and I see no end to this sender-initiated use of fax.

Five years ago every office had a FAX machine. Have you noticed that a 
lot now do not? Also, for those that do, it is often a dusty machine in 
the corner that is rarely used?

> It's worth pointing out that e-mail works off of a different premise 
> than fax, and therefore cannot ever fully obsolete fax as it is.  
> Unlike a website or fax, e-mail does not provide a mechanism for both 
> the sender and the receiver to negotiate the communication and 
> presentation of the document.  E-mail permits the sender to send 
> arbitrary filetypes with arbitrary formatting which the receiver may 
> or may not be able to utilize easily.  With a website the receiver 
> should be aware of what they are clicking on, and with fax the 
> receiver "capabilities" are communicated at the outset to the sender, 
> and the sender must select tranmission parameters from those 
> capabilites.  Thus, with fax the sender can have a reasonably good 
> degree of confidence that when the receiver sends the confirmation 
> signal (MCF) that the receiver can view the document and that it

FAX provides zero confidence of communication. This is totally bogus. 
MCF means nothing at all. Paper jams, out of paper, FAXing into store 
and forward switches, etc. are just a few of the many reasons MCF is 
meaningless. They should all result in no MCF, but in the real world 
they don't. Even if the page comes out at my local FAX machine, unless I 
expecting the document and specifically collect it, it will go in the 
bin. All FAXes are now assumed to be junk mail, so secretaries no longer 
distribute them to people's desks (even if they have some idea which 
desk, which is frequently not the case). If they are multi-page, pages 
get lost and often only a partial FAX arrives. FAX has been my least 
reliable means of communication, and the most frustrating.

> appears to the receiver nearly exactly the same way as it appears to 
> the sender.  Not only can you not do this with e-mail, but furthermore 
> with e-mail you only know that your outbound mail relay has accepted 
> the mail or not.  You do not have any reassurance that that the 
> intended recipient actually did receive the message.  And with the 
> large amount of spam out there (very large in comparison to the 
> quantity of junk faxes), spam filters, e-mail viruses, and such, 
> e-mail really isn't a very good means to transmit these kinds of things.

You have no idea where a FAX goes at all. Unless I know one is coming it 
will normally end up in the bin. An e-mail will always reach my desk, 
unless it gets mistaken as spam and dumped by filters.

> The fact that faxing has traditionally been done over POTS/PSTN lines 
> is largely irrelevant, I think.  Technology such as VoIP/FoIP is 
> providing a means for fax to utilize the internet, and I only suspect 
> to see an increase in the demand for fax-ready or fax-aware VoIP 
> equipment or software.  So fax modems may become obsoleted with the 
> growth of the internet (it's going to take a long while for broadband 
> to get to everyone with a fax application, though), but fax itself 
> will still be there, running on things such as t38modem and your 
> spandsp/rxfax/txfax.  It's not going away.

Except for the last sentance, this is true.

> V.34-Fax is a smart thing for fax.  Not only does it make the total 
> communication take less time in most cases, but the fact that V.34 is 
> used continuously throughout the session *without dropping and raising 
> the carriers* makes it very stable.  Without V.34-Fax you have to drop 
> and raise the V.17/V.29/V.27 primary carrier and the V.21 control 
> carrier frequently, and every time that happens there is a risk of 
> losing synchronicity due to noise or timing problems.

I find no problems with V.17/V.29/V.27 on reasonable phone lines, and on 
poor phone lines V.34 will not work. I find this statement rather odd. 
However, continuous duplex operation certainly speeds things up more 
that the 28800/14400 ratio between V.34 and V.17 would indicate.

> Fax machine manufacturers that want to have happy customers first make 
> sure their products supports ECM (requires 64K RAM per line, so there 
> is an actual hardware difference - not just firmware).  Users won't 
> know what this means, except that they'll get perfect faxes nearly 
> every time.  They'll eventually toss those cheap non-ECM fax machines 
> when they have communication problems that are resolved when they go 
> and buy a nicer ECM-supporting fax machine.  They won't realize that 
> it was ECM, they'll just know that the cheap fax machine didn't do as 
> good a job as the not-as-cheap one.  Likewise manufacturers that want 
> happy customers will implement V.34-Fax not just for faster faxing, 
> but because it provides a more stable fax medium.


> So, I guess what I'm saying, is that inevitably there is going to be 
> an FoIP solution that supports both ECM and V.34-Fax.  If you want 
> your product to be the standard-bearer, well, thinking that fax is 
> obsolete will not be helpful.  :-)  If you really are looking for the 
> path of least effort, I would recommend that you forget most of the 
> fax protocol - like t38modem, leaving the faxing up to applications 
> like HylaFAX, efax, or whatever - and merely work at an AT-command 
> interface (Class 1/1.0 should be sufficient) application for spandsp, 
> say "spandspmodem".  That should be significantly more simple.

My goal with spandsp is to provide a very low cost method to provide 
adequate support for the steadily dwindling, and largely deprecated, FAX 
traffic. This ain't no growth market. The idea of standards bearing is a 

I observe FAX as now restricted to 2 uses:

- Older managers will never change, and still think FAX is really neat 
new technology. All their e-mails are currently printed for them to 
read. This kind of use will persist until that generation has mostly 

- People need to send hand completed forms, signed documents, and hand 
marked up sheets. The clunkiness of dealing with these as e-mail 
attachments has limited migration away from FAX here. However, things 
like the all in one scan and print machines, and better software are 
slowly changing things. I suspect this use will take a long time to die 
completely, but it will. Right now I see lots of people sending a little 
e-mail to warn the recipient to go pick up the sheets from the FAX 
machine. :-)


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